Merge branch 'main' into disclosable-component

.github/workflows/publish_collab_image.yml

@@ -11,7 +11,7 @@ env:
 
 jobs:
   publish:
-    name: Publish collab server image 
+    name: Publish collab server image
     runs-on:
       - self-hosted
       - deploy
@@ -22,6 +22,9 @@ jobs:
       - name: Sign into DigitalOcean docker registry
         run: doctl registry login
 
+      - name: Prune Docker system
+        run: docker system prune
+
       - name: Checkout repo
         uses: actions/checkout@v3
         with:
@@ -41,6 +44,6 @@ jobs:
 
       - name: Build docker image
         run: docker build . --tag registry.digitalocean.com/zed/collab:v${COLLAB_VERSION}
-    
+
       - name: Publish docker image
         run: docker push registry.digitalocean.com/zed/collab:v${COLLAB_VERSION}

Cargo.lock

@@ -1312,12 +1312,6 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2da6da31387c7e4ef160ffab6d5e7f00c42626fe39aea70a7b0f1773f7dd6c1b"
 
-[[package]]
-name = "claxon"
-version = "0.4.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4bfbf56724aa9eca8afa4fcfadeb479e722935bb2a0900c2d37e0cc477af0688"
-
 [[package]]
 name = "cli"
 version = "0.1.0"
@@ -1415,7 +1409,7 @@ dependencies = [
 
 [[package]]
 name = "collab"
-version = "0.17.0"
+version = "0.18.0"
 dependencies = [
  "anyhow",
  "async-tungstenite",
@@ -2104,6 +2098,15 @@ dependencies = [
  "syn 1.0.109",
 ]
 
+[[package]]
+name = "derive_refineable"
+version = "0.1.0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "dhat"
 version = "0.3.2"
@@ -3086,6 +3089,7 @@ dependencies = [
  "png",
  "postage",
  "rand 0.8.5",
+ "refineable",
  "resvg",
  "schemars",
  "seahash",
@@ -3097,6 +3101,7 @@ dependencies = [
  "smol",
  "sqlez",
  "sum_tree",
+ "taffy",
  "time 0.3.24",
  "tiny-skia",
  "usvg",
@@ -3109,11 +3114,18 @@ dependencies = [
 name = "gpui_macros"
 version = "0.1.0"
 dependencies = [
+ "lazy_static",
  "proc-macro2",
  "quote",
  "syn 1.0.109",
 ]
 
+[[package]]
+name = "grid"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eec1c01eb1de97451ee0d60de7d81cf1e72aabefb021616027f3d1c3ec1c723c"
+
 [[package]]
 name = "h2"
 version = "0.3.20"
@@ -3903,17 +3915,6 @@ version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "884e2677b40cc8c339eaefcb701c32ef1fd2493d71118dc0ca4b6a736c93bd67"
 
-[[package]]
-name = "lewton"
-version = "0.10.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "777b48df9aaab155475a83a7df3070395ea1ac6902f5cd062b8f2b028075c030"
-dependencies = [
- "byteorder",
- "ogg",
- "tinyvec",
-]
-
 [[package]]
 name = "libc"
 version = "0.2.147"
@@ -4767,15 +4768,6 @@ dependencies = [
  "cc",
 ]
 
-[[package]]
-name = "ogg"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6951b4e8bf21c8193da321bcce9c9dd2e13c858fe078bf9054a288b419ae5d6e"
-dependencies = [
- "byteorder",
-]
-
 [[package]]
 name = "once_cell"
 version = "1.18.0"
@@ -5126,6 +5118,33 @@ version = "0.3.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "26072860ba924cbfa98ea39c8c19b4dd6a4a25423dbdf219c1eca91aa0cf6964"
 
+[[package]]
+name = "playground"
+version = "0.1.0"
+dependencies = [
+ "anyhow",
+ "derive_more",
+ "gpui",
+ "log",
+ "parking_lot 0.11.2",
+ "playground_macros",
+ "refineable",
+ "serde",
+ "simplelog",
+ "smallvec",
+ "taffy",
+ "util",
+]
+
+[[package]]
+name = "playground_macros"
+version = "0.1.0"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "plist"
 version = "1.5.0"
@@ -5803,6 +5822,16 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "refineable"
+version = "0.1.0"
+dependencies = [
+ "derive_refineable",
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "regalloc2"
 version = "0.2.3"
@@ -6021,11 +6050,8 @@ version = "0.17.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bdf1d4dea18dff2e9eb6dca123724f8b60ef44ad74a9ad283cdfe025df7e73fa"
 dependencies = [
- "claxon",
  "cpal",
  "hound",
- "lewton",
- "symphonia",
 ]
 
 [[package]]
@@ -6117,9 +6143,9 @@ dependencies = [
 
 [[package]]
 name = "rust-embed"
-version = "6.8.1"
+version = "8.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a36224c3276f8c4ebc8c20f158eca7ca4359c8db89991c4925132aaaf6702661"
+checksum = "b1e7d90385b59f0a6bf3d3b757f3ca4ece2048265d70db20a2016043d4509a40"
 dependencies = [
  "rust-embed-impl",
  "rust-embed-utils",
@@ -6128,9 +6154,9 @@ dependencies = [
 
 [[package]]
 name = "rust-embed-impl"
-version = "6.8.1"
+version = "8.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49b94b81e5b2c284684141a2fb9e2a31be90638caf040bf9afbc5a0416afe1ac"
+checksum = "3c3d8c6fd84090ae348e63a84336b112b5c3918b3bf0493a581f7bd8ee623c29"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -6141,9 +6167,9 @@ dependencies = [
 
 [[package]]
 name = "rust-embed-utils"
-version = "7.8.1"
+version = "8.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9d38ff6bf570dc3bb7100fce9f7b60c33fa71d80e88da3f2580df4ff2bdded74"
+checksum = "873feff8cb7bf86fdf0a71bb21c95159f4e4a37dd7a4bd1855a940909b583ada"
 dependencies = [
  "globset",
  "sha2 0.10.7",
@@ -6971,6 +6997,15 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "826167069c09b99d56f31e9ae5c99049e932a98c9dc2dac47645b08dbbf76ba7"
 
+[[package]]
+name = "slotmap"
+version = "1.0.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e1e08e261d0e8f5c43123b7adf3e4ca1690d655377ac93a03b2c9d3e98de1342"
+dependencies = [
+ "version_check",
+]
+
 [[package]]
 name = "sluice"
 version = "0.5.5"
@@ -7341,56 +7376,6 @@ dependencies = [
  "siphasher",
 ]
 
-[[package]]
-name = "symphonia"
-version = "0.5.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "62e48dba70095f265fdb269b99619b95d04c89e619538138383e63310b14d941"
-dependencies = [
- "lazy_static",
- "symphonia-bundle-mp3",
- "symphonia-core",
- "symphonia-metadata",
-]
-
-[[package]]
-name = "symphonia-bundle-mp3"
-version = "0.5.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0f31d7fece546f1e6973011a9eceae948133bbd18fd3d52f6073b1e38ae6368a"
-dependencies = [
- "bitflags 1.3.2",
- "lazy_static",
- "log",
- "symphonia-core",
- "symphonia-metadata",
-]
-
-[[package]]
-name = "symphonia-core"
-version = "0.5.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f7c73eb88fee79705268cc7b742c7bc93a7b76e092ab751d0833866970754142"
-dependencies = [
- "arrayvec 0.7.4",
- "bitflags 1.3.2",
- "bytemuck",
- "lazy_static",
- "log",
-]
-
-[[package]]
-name = "symphonia-metadata"
-version = "0.5.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "89c3e1937e31d0e068bbe829f66b2f2bfaa28d056365279e0ef897172c3320c0"
-dependencies = [
- "encoding_rs",
- "lazy_static",
- "log",
- "symphonia-core",
-]
-
 [[package]]
 name = "syn"
 version = "1.0.109"
@@ -7460,6 +7445,17 @@ dependencies = [
  "winx",
 ]
 
+[[package]]
+name = "taffy"
+version = "0.3.11"
+source = "git+https://github.com/DioxusLabs/taffy?rev=dab541d6104d58e2e10ce90c4a1dad0b703160cd#dab541d6104d58e2e10ce90c4a1dad0b703160cd"
+dependencies = [
+ "arrayvec 0.7.4",
+ "grid",
+ "num-traits",
+ "slotmap",
+]
+
 [[package]]
 name = "take-until"
 version = "0.2.0"
@@ -9649,7 +9645,7 @@ dependencies = [
 
 [[package]]
 name = "zed"
-version = "0.101.0"
+version = "0.102.0"
 dependencies = [
  "activity_indicator",
  "ai",

Cargo.toml

@@ -18,6 +18,8 @@ members = [
     "crates/copilot",
     "crates/copilot_button",
     "crates/db",
+    "crates/refineable",
+    "crates/refineable/derive_refineable",
     "crates/diagnostics",
     "crates/drag_and_drop",
     "crates/editor",
@@ -29,6 +31,8 @@ members = [
     "crates/git",
     "crates/go_to_line",
     "crates/gpui",
+    "crates/gpui/playground",
+    "crates/gpui/playground_macros",
     "crates/gpui_macros",
     "crates/install_cli",
     "crates/journal",
@@ -93,8 +97,9 @@ ordered-float = { version = "2.1.1" }
 parking_lot = { version = "0.11.1" }
 postage = { version = "0.5", features = ["futures-traits"] }
 rand = { version = "0.8.5" }
+refineable = { path = "./crates/refineable" }
 regex = { version = "1.5" }
-rust-embed = { version = "6.3", features = ["include-exclude"] }
+rust-embed = { version = "8.0", features = ["include-exclude"] }
 schemars = { version = "0.8" }
 serde = { version = "1.0", features = ["derive", "rc"] }
 serde_derive = { version = "1.0", features = ["deserialize_in_place"] }

assets/keymaps/default.json

@@ -543,6 +543,8 @@
     "bindings": {
       "left": "project_panel::CollapseSelectedEntry",
       "right": "project_panel::ExpandSelectedEntry",
+      "cmd-n": "project_panel::NewFile",
+      "alt-cmd-n": "project_panel::NewDirectory",
       "cmd-x": "project_panel::Cut",
       "cmd-c": "project_panel::Copy",
       "cmd-v": "project_panel::Paste",

assets/keymaps/textmate.json

@@ -2,7 +2,6 @@
   {
     "bindings": {
       "cmd-shift-o": "projects::OpenRecent",
-      "cmd-shift-b": "branches::OpenRecent",
       "cmd-alt-tab": "project_panel::ToggleFocus"
     }
   },
@@ -12,8 +11,9 @@
       "cmd-l": "go_to_line::Toggle",
       "ctrl-shift-d": "editor::DuplicateLine",
       "cmd-b": "editor::GoToDefinition",
-      "alt-cmd-b": "editor::GoToDefinition",
       "cmd-j": "editor::ScrollCursorCenter",
+      "cmd-enter": "editor::NewlineBelow",
+      "cmd-alt-enter": "editor::NewLineAbove",
       "cmd-shift-l": "editor::SelectLine",
       "cmd-shift-t": "outline::Toggle",
       "alt-backspace": "editor::DeleteToPreviousWordStart",
@@ -51,14 +51,17 @@
         }
       ],
       "ctrl-shift-left": "editor::SelectToPreviousSubwordStart",
-      "ctrl-shift-right": "editor::SelectToNextSubwordEnd"
+      "ctrl-shift-right": "editor::SelectToNextSubwordEnd",
+      "ctrl-w": "editor::SelectNext",
+      "ctrl-u": "editor::ConvertToUpperCase",
+      "ctrl-shift-u": "editor::ConvertToLowerCase",
+      "ctrl-alt-u": "editor::ConvertToUpperCamelCase",
+      "ctrl-_": "editor::ConvertToSnakeCase"
     }
   },
   {
     "context": "Editor && mode == full",
-    "bindings": {
+    "bindings": {}
-      "cmd-alt-enter": "editor::NewlineAbove"
-    }
   },
   {
     "context": "BufferSearchBar",
@@ -85,5 +88,9 @@
   {
     "context": "ProjectPanel",
     "bindings": {}
+  },
+  {
+    "context": "Dock",
+    "bindings": {}
   }
 ]

assets/keymaps/vim.json

@@ -287,6 +287,12 @@
       "shift-o": "vim::InsertLineAbove",
       "~": "vim::ChangeCase",
       "p": "vim::Paste",
+      "shift-p": [
+        "vim::Paste",
+        {
+          "before": true
+        }
+      ],
       "u": "editor::Undo",
       "ctrl-r": "editor::Redo",
       "/": "vim::Search",
@@ -375,7 +381,13 @@
       "d": "vim::VisualDelete",
       "x": "vim::VisualDelete",
       "y": "vim::VisualYank",
-      "p": "vim::VisualPaste",
+      "p": "vim::Paste",
+      "shift-p": [
+        "vim::Paste",
+        {
+          "preserveClipboard": true
+        }
+      ],
       "s": "vim::Substitute",
       "c": "vim::Substitute",
       "~": "vim::ChangeCase",
@@ -421,7 +433,7 @@
     }
   },
   {
-    "context": "Editor && vim_mode == insert",
+    "context": "Editor && vim_mode == insert && !menu",
     "bindings": {
       "escape": "vim::NormalBefore",
       "ctrl-c": "vim::NormalBefore",

assets/settings/default.json

@@ -138,7 +138,13 @@
     // Default width when the assistant is docked to the left or right.
     "default_width": 640,
     // Default height when the assistant is docked to the bottom.
-    "default_height": 320
+    "default_height": 320,
+    // The default OpenAI model to use when starting new conversations. This
+    // setting can take two values:
+    //
+    // 1. "gpt-3.5-turbo-0613""
+    // 2. "gpt-4-0613""
+    "default_open_ai_model": "gpt-4-0613"
   },
   // Whether the screen sharing icon is shown in the os status bar.
   "show_call_status_icon": true,

crates/ai/src/ai.rs

@@ -3,6 +3,7 @@ mod assistant_settings;
 
 use anyhow::Result;
 pub use assistant::AssistantPanel;
+use assistant_settings::OpenAIModel;
 use chrono::{DateTime, Local};
 use collections::HashMap;
 use fs::Fs;
@@ -60,7 +61,7 @@ struct SavedConversation {
     messages: Vec<SavedMessage>,
     message_metadata: HashMap<MessageId, MessageMetadata>,
     summary: String,
-    model: String,
+    model: OpenAIModel,
 }
 
 impl SavedConversation {

crates/ai/src/assistant.rs

@@ -1,5 +1,5 @@
 use crate::{
-    assistant_settings::{AssistantDockPosition, AssistantSettings},
+    assistant_settings::{AssistantDockPosition, AssistantSettings, OpenAIModel},
     MessageId, MessageMetadata, MessageStatus, OpenAIRequest, OpenAIResponseStreamEvent,
     RequestMessage, Role, SavedConversation, SavedConversationMetadata, SavedMessage,
 };
@@ -833,7 +833,7 @@ struct Conversation {
     pending_summary: Task<Option<()>>,
     completion_count: usize,
     pending_completions: Vec<PendingCompletion>,
-    model: String,
+    model: OpenAIModel,
     token_count: Option<usize>,
     max_token_count: usize,
     pending_token_count: Task<Option<()>>,
@@ -853,7 +853,6 @@ impl Conversation {
         language_registry: Arc<LanguageRegistry>,
         cx: &mut ModelContext<Self>,
     ) -> Self {
-        let model = "gpt-3.5-turbo-0613";
         let markdown = language_registry.language_for_name("Markdown");
         let buffer = cx.add_model(|cx| {
             let mut buffer = Buffer::new(0, "", cx);
@@ -872,6 +871,9 @@ impl Conversation {
             buffer
         });
 
+        let settings = settings::get::<AssistantSettings>(cx);
+        let model = settings.default_open_ai_model.clone();
+
         let mut this = Self {
             message_anchors: Default::default(),
             messages_metadata: Default::default(),
@@ -881,9 +883,9 @@ impl Conversation {
             completion_count: Default::default(),
             pending_completions: Default::default(),
             token_count: None,
-            max_token_count: tiktoken_rs::model::get_context_size(model),
+            max_token_count: tiktoken_rs::model::get_context_size(&model.full_name()),
             pending_token_count: Task::ready(None),
-            model: model.into(),
+            model: model.clone(),
             _subscriptions: vec![cx.subscribe(&buffer, Self::handle_buffer_event)],
             pending_save: Task::ready(Ok(())),
             path: None,
@@ -977,7 +979,7 @@ impl Conversation {
             completion_count: Default::default(),
             pending_completions: Default::default(),
             token_count: None,
-            max_token_count: tiktoken_rs::model::get_context_size(&model),
+            max_token_count: tiktoken_rs::model::get_context_size(&model.full_name()),
             pending_token_count: Task::ready(None),
             model,
             _subscriptions: vec![cx.subscribe(&buffer, Self::handle_buffer_event)],
@@ -1031,13 +1033,16 @@ impl Conversation {
                 cx.background().timer(Duration::from_millis(200)).await;
                 let token_count = cx
                     .background()
-                    .spawn(async move { tiktoken_rs::num_tokens_from_messages(&model, &messages) })
+                    .spawn(async move {
+                        tiktoken_rs::num_tokens_from_messages(&model.full_name(), &messages)
+                    })
                     .await?;
 
                 this.upgrade(&cx)
                     .ok_or_else(|| anyhow!("conversation was dropped"))?
                     .update(&mut cx, |this, cx| {
-                        this.max_token_count = tiktoken_rs::model::get_context_size(&this.model);
+                        this.max_token_count =
+                            tiktoken_rs::model::get_context_size(&this.model.full_name());
                         this.token_count = Some(token_count);
                         cx.notify()
                     });
@@ -1051,7 +1056,7 @@ impl Conversation {
         Some(self.max_token_count as isize - self.token_count? as isize)
     }
 
-    fn set_model(&mut self, model: String, cx: &mut ModelContext<Self>) {
+    fn set_model(&mut self, model: OpenAIModel, cx: &mut ModelContext<Self>) {
         self.model = model;
         self.count_remaining_tokens(cx);
         cx.notify();
@@ -1093,7 +1098,7 @@ impl Conversation {
                 }
             } else {
                 let request = OpenAIRequest {
-                    model: self.model.clone(),
+                    model: self.model.full_name().to_string(),
                     messages: self
                         .messages(cx)
                         .filter(|message| matches!(message.status, MessageStatus::Done))
@@ -1419,7 +1424,7 @@ impl Conversation {
                                 .into(),
                     }));
                 let request = OpenAIRequest {
-                    model: self.model.clone(),
+                    model: self.model.full_name().to_string(),
                     messages: messages.collect(),
                     stream: true,
                 };
@@ -2023,11 +2028,8 @@ impl ConversationEditor {
 
     fn cycle_model(&mut self, cx: &mut ViewContext<Self>) {
         self.conversation.update(cx, |conversation, cx| {
-            let new_model = match conversation.model.as_str() {
+            let new_model = conversation.model.cycle();
-                "gpt-4-0613" => "gpt-3.5-turbo-0613",
+            conversation.set_model(new_model, cx);
-                _ => "gpt-4-0613",
-            };
-            conversation.set_model(new_model.into(), cx);
         });
     }
 
@@ -2049,7 +2051,8 @@ impl ConversationEditor {
 
         MouseEventHandler::new::<Model, _>(0, cx, |state, cx| {
             let style = style.model.style_for(state);
-            Label::new(self.conversation.read(cx).model.clone(), style.text.clone())
+            let model_display_name = self.conversation.read(cx).model.short_name();
+            Label::new(model_display_name, style.text.clone())
                 .contained()
                 .with_style(style.container)
         })
@@ -2238,6 +2241,8 @@ mod tests {
 
     #[gpui::test]
     fn test_inserting_and_removing_messages(cx: &mut AppContext) {
+        cx.set_global(SettingsStore::test(cx));
+        init(cx);
         let registry = Arc::new(LanguageRegistry::test());
         let conversation = cx.add_model(|cx| Conversation::new(Default::default(), registry, cx));
         let buffer = conversation.read(cx).buffer.clone();
@@ -2364,6 +2369,8 @@ mod tests {
 
     #[gpui::test]
     fn test_message_splitting(cx: &mut AppContext) {
+        cx.set_global(SettingsStore::test(cx));
+        init(cx);
         let registry = Arc::new(LanguageRegistry::test());
         let conversation = cx.add_model(|cx| Conversation::new(Default::default(), registry, cx));
         let buffer = conversation.read(cx).buffer.clone();
@@ -2458,6 +2465,8 @@ mod tests {
 
     #[gpui::test]
     fn test_messages_for_offsets(cx: &mut AppContext) {
+        cx.set_global(SettingsStore::test(cx));
+        init(cx);
         let registry = Arc::new(LanguageRegistry::test());
         let conversation = cx.add_model(|cx| Conversation::new(Default::default(), registry, cx));
         let buffer = conversation.read(cx).buffer.clone();
@@ -2538,6 +2547,8 @@ mod tests {
 
     #[gpui::test]
     fn test_serialization(cx: &mut AppContext) {
+        cx.set_global(SettingsStore::test(cx));
+        init(cx);
         let registry = Arc::new(LanguageRegistry::test());
         let conversation =
             cx.add_model(|cx| Conversation::new(Default::default(), registry.clone(), cx));

crates/ai/src/assistant_settings.rs

@@ -3,6 +3,37 @@ use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 use settings::Setting;
 
+#[derive(Clone, Debug, Serialize, Deserialize, JsonSchema, PartialEq)]
+pub enum OpenAIModel {
+    #[serde(rename = "gpt-3.5-turbo-0613")]
+    ThreePointFiveTurbo,
+    #[serde(rename = "gpt-4-0613")]
+    Four,
+}
+
+impl OpenAIModel {
+    pub fn full_name(&self) -> &'static str {
+        match self {
+            OpenAIModel::ThreePointFiveTurbo => "gpt-3.5-turbo-0613",
+            OpenAIModel::Four => "gpt-4-0613",
+        }
+    }
+
+    pub fn short_name(&self) -> &'static str {
+        match self {
+            OpenAIModel::ThreePointFiveTurbo => "gpt-3.5-turbo",
+            OpenAIModel::Four => "gpt-4",
+        }
+    }
+
+    pub fn cycle(&self) -> Self {
+        match self {
+            OpenAIModel::ThreePointFiveTurbo => OpenAIModel::Four,
+            OpenAIModel::Four => OpenAIModel::ThreePointFiveTurbo,
+        }
+    }
+}
+
 #[derive(Clone, Debug, Serialize, Deserialize, JsonSchema)]
 #[serde(rename_all = "snake_case")]
 pub enum AssistantDockPosition {
@@ -17,6 +48,7 @@ pub struct AssistantSettings {
     pub dock: AssistantDockPosition,
     pub default_width: f32,
     pub default_height: f32,
+    pub default_open_ai_model: OpenAIModel,
 }
 
 #[derive(Clone, Default, Serialize, Deserialize, JsonSchema, Debug)]
@@ -25,6 +57,7 @@ pub struct AssistantSettingsContent {
     pub dock: Option<AssistantDockPosition>,
     pub default_width: Option<f32>,
     pub default_height: Option<f32>,
+    pub default_open_ai_model: Option<OpenAIModel>,
 }
 
 impl Setting for AssistantSettings {

crates/audio/Cargo.toml

@@ -13,7 +13,7 @@ gpui = { path = "../gpui" }
 collections = { path = "../collections" }
 util = { path = "../util" }
 
-rodio = "0.17.1"
+rodio ={version = "0.17.1", default-features=false, features = ["wav"]}
 
 log.workspace = true
 

crates/call/src/call.rs

@@ -274,7 +274,7 @@ impl ActiveCall {
             .borrow_mut()
             .take()
             .ok_or_else(|| anyhow!("no incoming call"))?;
-        Self::report_call_event_for_room("decline incoming", call.room_id, &self.client, cx);
+        Self::report_call_event_for_room("decline incoming", call.room_id, None, &self.client, cx);
         self.client.send(proto::DeclineCall {
             room_id: call.room_id,
         })?;
@@ -406,19 +406,31 @@ impl ActiveCall {
 
     fn report_call_event(&self, operation: &'static str, cx: &AppContext) {
         if let Some(room) = self.room() {
-            Self::report_call_event_for_room(operation, room.read(cx).id(), &self.client, cx)
+            let room = room.read(cx);
+            Self::report_call_event_for_room(
+                operation,
+                room.id(),
+                room.channel_id(),
+                &self.client,
+                cx,
+            )
         }
     }
 
     pub fn report_call_event_for_room(
         operation: &'static str,
         room_id: u64,
+        channel_id: Option<u64>,
         client: &Arc<Client>,
         cx: &AppContext,
     ) {
         let telemetry = client.telemetry();
         let telemetry_settings = *settings::get::<TelemetrySettings>(cx);
-        let event = ClickhouseEvent::Call { operation, room_id };
+        let event = ClickhouseEvent::Call {
+            operation,
+            room_id,
+            channel_id,
+        };
         telemetry.report_clickhouse_event(event, telemetry_settings);
     }
 }

crates/client/src/telemetry.rs

@@ -74,6 +74,7 @@ pub enum ClickhouseEvent {
     Call {
         operation: &'static str,
         room_id: u64,
+        channel_id: Option<u64>,
     },
 }
 

crates/collab/Cargo.toml

@@ -3,7 +3,7 @@ authors = ["Nathan Sobo <nathan@zed.dev>"]
 default-run = "collab"
 edition = "2021"
 name = "collab"
-version = "0.17.0"
+version = "0.18.0"
 publish = false
 
 [[bin]]

crates/collab_ui/src/collab_titlebar_item.rs

@@ -1096,7 +1096,7 @@ impl CollabTitlebarItem {
         style
     }
 
-    fn render_face<V: View>(
+    fn render_face<V: 'static>(
         avatar: Arc<ImageData>,
         avatar_style: AvatarStyle,
         background_color: Color,

crates/collab_ui/src/collab_ui.rs

@@ -49,6 +49,7 @@ pub fn toggle_screen_sharing(_: &ToggleScreenSharing, cx: &mut AppContext) {
                 ActiveCall::report_call_event_for_room(
                     "disable screen share",
                     room.id(),
+                    room.channel_id(),
                     &client,
                     cx,
                 );
@@ -57,6 +58,7 @@ pub fn toggle_screen_sharing(_: &ToggleScreenSharing, cx: &mut AppContext) {
                 ActiveCall::report_call_event_for_room(
                     "enable screen share",
                     room.id(),
+                    room.channel_id(),
                     &client,
                     cx,
                 );
@@ -73,11 +75,18 @@ pub fn toggle_mute(_: &ToggleMute, cx: &mut AppContext) {
         let client = call.client();
         room.update(cx, |room, cx| {
             if room.is_muted(cx) {
-                ActiveCall::report_call_event_for_room("enable microphone", room.id(), &client, cx);
+                ActiveCall::report_call_event_for_room(
+                    "enable microphone",
+                    room.id(),
+                    room.channel_id(),
+                    &client,
+                    cx,
+                );
             } else {
                 ActiveCall::report_call_event_for_room(
                     "disable microphone",
                     room.id(),
+                    room.channel_id(),
                     &client,
                     cx,
                 );

crates/collab_ui/src/notifications.rs

@@ -2,14 +2,14 @@ use client::User;
 use gpui::{
     elements::*,
     platform::{CursorStyle, MouseButton},
-    AnyElement, Element, View, ViewContext,
+    AnyElement, Element, ViewContext,
 };
 use std::sync::Arc;
 
 enum Dismiss {}
 enum Button {}
 
-pub fn render_user_notification<F, V>(
+pub fn render_user_notification<F, V: 'static>(
     user: Arc<User>,
     title: &'static str,
     body: Option<&'static str>,
@@ -19,7 +19,6 @@ pub fn render_user_notification<F, V>(
 ) -> AnyElement<V>
 where
     F: 'static + Fn(&mut V, &mut ViewContext<V>),
-    V: View,
 {
     let theme = theme::current(cx).clone();
     let theme = &theme.contact_notification;

crates/component_test/src/component_test.rs

@@ -1,6 +1,5 @@
 use gpui::{
     actions,
-    color::Color,
     elements::{Component, Flex, ParentElement, SafeStylable},
     AppContext, Element, Entity, ModelHandle, Task, View, ViewContext, ViewHandle, WeakViewHandle,
 };
@@ -97,7 +96,7 @@ impl View for ComponentTest {
 }
 
 impl Item for ComponentTest {
-    fn tab_content<V: View>(
+    fn tab_content<V: 'static>(
         &self,
         _: Option<usize>,
         style: &theme::Tab,

crates/diagnostics/src/diagnostics.rs

@@ -538,7 +538,7 @@ impl ProjectDiagnosticsEditor {
 }
 
 impl Item for ProjectDiagnosticsEditor {
-    fn tab_content<T: View>(
+    fn tab_content<T: 'static>(
         &self,
         _detail: Option<usize>,
         style: &theme::Tab,
@@ -735,7 +735,7 @@ fn diagnostic_header_renderer(diagnostic: Diagnostic) -> RenderBlock {
     })
 }
 
-pub(crate) fn render_summary<T: View>(
+pub(crate) fn render_summary<T: 'static>(
     summary: &DiagnosticSummary,
     text_style: &TextStyle,
     theme: &theme::ProjectDiagnostics,

crates/drag_and_drop/src/drag_and_drop.rs

@@ -11,7 +11,7 @@ use gpui::{
 
 const DEAD_ZONE: f32 = 4.;
 
-enum State<V: View> {
+enum State<V> {
     Down {
         region_offset: Vector2F,
         region: RectF,
@@ -31,7 +31,7 @@ enum State<V: View> {
     Canceled,
 }
 
-impl<V: View> Clone for State<V> {
+impl<V> Clone for State<V> {
     fn clone(&self) -> Self {
         match self {
             &State::Down {
@@ -68,12 +68,12 @@ impl<V: View> Clone for State<V> {
     }
 }
 
-pub struct DragAndDrop<V: View> {
+pub struct DragAndDrop<V> {
     containers: HashSet<WeakViewHandle<V>>,
     currently_dragged: Option<State<V>>,
 }
 
-impl<V: View> Default for DragAndDrop<V> {
+impl<V> Default for DragAndDrop<V> {
     fn default() -> Self {
         Self {
             containers: Default::default(),
@@ -82,7 +82,7 @@ impl<V: View> Default for DragAndDrop<V> {
     }
 }
 
-impl<V: View> DragAndDrop<V> {
+impl<V: 'static> DragAndDrop<V> {
     pub fn register_container(&mut self, handle: WeakViewHandle<V>) {
         self.containers.insert(handle);
     }
@@ -291,7 +291,7 @@ impl<V: View> DragAndDrop<V> {
     }
 }
 
-pub trait Draggable<V: View> {
+pub trait Draggable<V> {
     fn as_draggable<D: View, P: Any>(
         self,
         payload: P,
@@ -301,7 +301,7 @@ pub trait Draggable<V: View> {
         Self: Sized;
 }
 
-impl<V: View> Draggable<V> for MouseEventHandler<V> {
+impl<V: 'static> Draggable<V> for MouseEventHandler<V> {
     fn as_draggable<D: View, P: Any>(
         self,
         payload: P,

crates/editor/src/editor.rs

@@ -1736,6 +1736,31 @@ impl Editor {
         });
     }
 
+    pub fn edit_with_block_indent<I, S, T>(
+        &mut self,
+        edits: I,
+        original_indent_columns: Vec<u32>,
+        cx: &mut ViewContext<Self>,
+    ) where
+        I: IntoIterator<Item = (Range<S>, T)>,
+        S: ToOffset,
+        T: Into<Arc<str>>,
+    {
+        if self.read_only {
+            return;
+        }
+
+        self.buffer.update(cx, |buffer, cx| {
+            buffer.edit(
+                edits,
+                Some(AutoindentMode::Block {
+                    original_indent_columns,
+                }),
+                cx,
+            )
+        });
+    }
+
     fn select(&mut self, phase: SelectPhase, cx: &mut ViewContext<Self>) {
         self.hide_context_menu(cx);
 
@@ -2667,7 +2692,6 @@ impl Editor {
             false
         });
     }
-
     fn completion_query(buffer: &MultiBufferSnapshot, position: impl ToOffset) -> Option<String> {
         let offset = position.to_offset(buffer);
         let (word_range, kind) = buffer.surrounding_word(offset);
@@ -4742,6 +4766,7 @@ impl Editor {
         let mut clipboard_selections = Vec::with_capacity(selections.len());
         {
             let max_point = buffer.max_point();
+            let mut is_first = true;
             for selection in &mut selections {
                 let is_entire_line = selection.is_empty() || self.selections.line_mode;
                 if is_entire_line {
@@ -4749,6 +4774,11 @@ impl Editor {
                     selection.end = cmp::min(max_point, Point::new(selection.end.row + 1, 0));
                     selection.goal = SelectionGoal::None;
                 }
+                if is_first {
+                    is_first = false;
+                } else {
+                    text += "\n";
+                }
                 let mut len = 0;
                 for chunk in buffer.text_for_range(selection.start..selection.end) {
                     text.push_str(chunk);
@@ -4779,6 +4809,7 @@ impl Editor {
         let mut clipboard_selections = Vec::with_capacity(selections.len());
         {
             let max_point = buffer.max_point();
+            let mut is_first = true;
             for selection in selections.iter() {
                 let mut start = selection.start;
                 let mut end = selection.end;
@@ -4787,6 +4818,11 @@ impl Editor {
                     start = Point::new(start.row, 0);
                     end = cmp::min(max_point, Point::new(end.row + 1, 0));
                 }
+                if is_first {
+                    is_first = false;
+                } else {
+                    text += "\n";
+                }
                 let mut len = 0;
                 for chunk in buffer.text_for_range(start..end) {
                     text.push_str(chunk);
@@ -4806,7 +4842,7 @@ impl Editor {
     pub fn paste(&mut self, _: &Paste, cx: &mut ViewContext<Self>) {
         self.transact(cx, |this, cx| {
             if let Some(item) = cx.read_from_clipboard() {
-                let mut clipboard_text = Cow::Borrowed(item.text());
+                let clipboard_text = Cow::Borrowed(item.text());
                 if let Some(mut clipboard_selections) = item.metadata::<Vec<ClipboardSelection>>() {
                     let old_selections = this.selections.all::<usize>(cx);
                     let all_selections_were_entire_line =
@@ -4814,18 +4850,7 @@ impl Editor {
                     let first_selection_indent_column =
                         clipboard_selections.first().map(|s| s.first_line_indent);
                     if clipboard_selections.len() != old_selections.len() {
-                        let mut newline_separated_text = String::new();
+                        clipboard_selections.drain(..);
-                        let mut clipboard_selections = clipboard_selections.drain(..).peekable();
-                        let mut ix = 0;
-                        while let Some(clipboard_selection) = clipboard_selections.next() {
-                            newline_separated_text
-                                .push_str(&clipboard_text[ix..ix + clipboard_selection.len]);
-                            ix += clipboard_selection.len;
-                            if clipboard_selections.peek().is_some() {
-                                newline_separated_text.push('\n');
-                            }
-                        }
-                        clipboard_text = Cow::Owned(newline_separated_text);
                     }
 
                     this.buffer.update(cx, |buffer, cx| {
@@ -4841,8 +4866,9 @@ impl Editor {
                             if let Some(clipboard_selection) = clipboard_selections.get(ix) {
                                 let end_offset = start_offset + clipboard_selection.len;
                                 to_insert = &clipboard_text[start_offset..end_offset];
+                                dbg!(start_offset, end_offset, &clipboard_text, &to_insert);
                                 entire_line = clipboard_selection.is_entire_line;
-                                start_offset = end_offset;
+                                start_offset = end_offset + 1;
                                 original_indent_column =
                                     Some(clipboard_selection.first_line_indent);
                             } else {
@@ -8537,6 +8563,7 @@ fn build_style(
                 font_size,
                 font_properties,
                 underline: Default::default(),
+                soft_wrap: false,
             },
             placeholder_text: None,
             line_height_scalar,

crates/editor/src/element.rs

@@ -605,7 +605,7 @@ impl EditorElement {
         visible_bounds: RectF,
         layout: &mut LayoutState,
         editor: &mut Editor,
-        cx: &mut ViewContext<Editor>,
+        cx: &mut PaintContext<Editor>,
     ) {
         let line_height = layout.position_map.line_height;
 
@@ -760,7 +760,7 @@ impl EditorElement {
         visible_bounds: RectF,
         layout: &mut LayoutState,
         editor: &mut Editor,
-        cx: &mut ViewContext<Editor>,
+        cx: &mut PaintContext<Editor>,
     ) {
         let style = &self.style;
         let local_replica_id = editor.replica_id(cx);
@@ -1337,7 +1337,7 @@ impl EditorElement {
         visible_bounds: RectF,
         layout: &mut LayoutState,
         editor: &mut Editor,
-        cx: &mut ViewContext<Editor>,
+        cx: &mut PaintContext<Editor>,
     ) {
         let scroll_position = layout.position_map.snapshot.scroll_position();
         let scroll_left = scroll_position.x() * layout.position_map.em_width;

crates/editor/src/items.rs

@@ -561,7 +561,7 @@ impl Item for Editor {
         }
     }
 
-    fn tab_content<T: View>(
+    fn tab_content<T: 'static>(
         &self,
         detail: Option<usize>,
         style: &theme::Tab,
@@ -1028,7 +1028,7 @@ impl SearchableItem for Editor {
             if let Some((_, _, excerpt_buffer)) = buffer.as_singleton() {
                 ranges.extend(
                     query
-                        .search(excerpt_buffer.as_rope())
+                        .search(excerpt_buffer, None)
                         .await
                         .into_iter()
                         .map(|range| {
@@ -1038,17 +1038,22 @@ impl SearchableItem for Editor {
             } else {
                 for excerpt in buffer.excerpt_boundaries_in_range(0..buffer.len()) {
                     let excerpt_range = excerpt.range.context.to_offset(&excerpt.buffer);
-                    let rope = excerpt.buffer.as_rope().slice(excerpt_range.clone());
+                    ranges.extend(
-                    ranges.extend(query.search(&rope).await.into_iter().map(|range| {
+                        query
-                        let start = excerpt
+                            .search(&excerpt.buffer, Some(excerpt_range.clone()))
-                            .buffer
+                            .await
-                            .anchor_after(excerpt_range.start + range.start);
+                            .into_iter()
-                        let end = excerpt
+                            .map(|range| {
-                            .buffer
+                                let start = excerpt
-                            .anchor_before(excerpt_range.start + range.end);
+                                    .buffer
-                        buffer.anchor_in_excerpt(excerpt.id.clone(), start)
+                                    .anchor_after(excerpt_range.start + range.start);
-                            ..buffer.anchor_in_excerpt(excerpt.id.clone(), end)
+                                let end = excerpt
-                    }));
+                                    .buffer
+                                    .anchor_before(excerpt_range.start + range.end);
+                                buffer.anchor_in_excerpt(excerpt.id.clone(), start)
+                                    ..buffer.anchor_in_excerpt(excerpt.id.clone(), end)
+                            }),
+                    );
                 }
             }
             ranges

crates/editor/src/movement.rs

@@ -176,14 +176,21 @@ pub fn line_end(
 }
 
 pub fn previous_word_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
+    let raw_point = point.to_point(map);
+    let language = map.buffer_snapshot.language_at(raw_point);
+
     find_preceding_boundary(map, point, |left, right| {
-        (char_kind(left) != char_kind(right) && !right.is_whitespace()) || left == '\n'
+        (char_kind(language, left) != char_kind(language, right) && !right.is_whitespace())
+            || left == '\n'
     })
 }
 
 pub fn previous_subword_start(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
+    let raw_point = point.to_point(map);
+    let language = map.buffer_snapshot.language_at(raw_point);
     find_preceding_boundary(map, point, |left, right| {
-        let is_word_start = char_kind(left) != char_kind(right) && !right.is_whitespace();
+        let is_word_start =
+            char_kind(language, left) != char_kind(language, right) && !right.is_whitespace();
         let is_subword_start =
             left == '_' && right != '_' || left.is_lowercase() && right.is_uppercase();
         is_word_start || is_subword_start || left == '\n'
@@ -191,14 +198,20 @@ pub fn previous_subword_start(map: &DisplaySnapshot, point: DisplayPoint) -> Dis
 }
 
 pub fn next_word_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
+    let raw_point = point.to_point(map);
+    let language = map.buffer_snapshot.language_at(raw_point);
     find_boundary(map, point, |left, right| {
-        (char_kind(left) != char_kind(right) && !left.is_whitespace()) || right == '\n'
+        (char_kind(language, left) != char_kind(language, right) && !left.is_whitespace())
+            || right == '\n'
     })
 }
 
 pub fn next_subword_end(map: &DisplaySnapshot, point: DisplayPoint) -> DisplayPoint {
+    let raw_point = point.to_point(map);
+    let language = map.buffer_snapshot.language_at(raw_point);
     find_boundary(map, point, |left, right| {
-        let is_word_end = (char_kind(left) != char_kind(right)) && !left.is_whitespace();
+        let is_word_end =
+            (char_kind(language, left) != char_kind(language, right)) && !left.is_whitespace();
         let is_subword_end =
             left != '_' && right == '_' || left.is_lowercase() && right.is_uppercase();
         is_word_end || is_subword_end || right == '\n'
@@ -385,10 +398,15 @@ pub fn find_boundary_in_line(
 }
 
 pub fn is_inside_word(map: &DisplaySnapshot, point: DisplayPoint) -> bool {
+    let raw_point = point.to_point(map);
+    let language = map.buffer_snapshot.language_at(raw_point);
     let ix = map.clip_point(point, Bias::Left).to_offset(map, Bias::Left);
     let text = &map.buffer_snapshot;
-    let next_char_kind = text.chars_at(ix).next().map(char_kind);
+    let next_char_kind = text.chars_at(ix).next().map(|c| char_kind(language, c));
-    let prev_char_kind = text.reversed_chars_at(ix).next().map(char_kind);
+    let prev_char_kind = text
+        .reversed_chars_at(ix)
+        .next()
+        .map(|c| char_kind(language, c));
     prev_char_kind.zip(next_char_kind) == Some((CharKind::Word, CharKind::Word))
 }
 

crates/editor/src/multi_buffer.rs

@@ -1346,10 +1346,7 @@ impl MultiBuffer {
             .map(|state| state.buffer.clone())
     }
 
-    pub fn is_completion_trigger<T>(&self, position: T, text: &str, cx: &AppContext) -> bool
+    pub fn is_completion_trigger(&self, position: Anchor, text: &str, cx: &AppContext) -> bool {
-    where
-        T: ToOffset,
-    {
         let mut chars = text.chars();
         let char = if let Some(char) = chars.next() {
             char
@@ -1360,7 +1357,9 @@ impl MultiBuffer {
             return false;
         }
 
-        if char.is_alphanumeric() || char == '_' {
+        let language = self.language_at(position.clone(), cx);
+
+        if char_kind(language.as_ref(), char) == CharKind::Word {
             return true;
         }
 
@@ -1865,13 +1864,16 @@ impl MultiBufferSnapshot {
         let mut end = start;
         let mut next_chars = self.chars_at(start).peekable();
         let mut prev_chars = self.reversed_chars_at(start).peekable();
+
+        let language = self.language_at(start);
+        let kind = |c| char_kind(language, c);
         let word_kind = cmp::max(
-            prev_chars.peek().copied().map(char_kind),
+            prev_chars.peek().copied().map(kind),
-            next_chars.peek().copied().map(char_kind),
+            next_chars.peek().copied().map(kind),
         );
 
         for ch in prev_chars {
-            if Some(char_kind(ch)) == word_kind && ch != '\n' {
+            if Some(kind(ch)) == word_kind && ch != '\n' {
                 start -= ch.len_utf8();
             } else {
                 break;
@@ -1879,7 +1881,7 @@ impl MultiBufferSnapshot {
         }
 
         for ch in next_chars {
-            if Some(char_kind(ch)) == word_kind && ch != '\n' {
+            if Some(kind(ch)) == word_kind && ch != '\n' {
                 end += ch.len_utf8();
             } else {
                 break;

crates/editor/src/test/editor_lsp_test_context.rs

@@ -6,6 +6,7 @@ use std::{
 
 use anyhow::Result;
 
+use collections::HashSet;
 use futures::Future;
 use gpui::{json, ViewContext, ViewHandle};
 use indoc::indoc;
@@ -154,10 +155,23 @@ impl<'a> EditorLspTestContext<'a> {
         capabilities: lsp::ServerCapabilities,
         cx: &'a mut gpui::TestAppContext,
     ) -> EditorLspTestContext<'a> {
+        let mut word_characters: HashSet<char> = Default::default();
+        word_characters.insert('$');
+        word_characters.insert('#');
         let language = Language::new(
             LanguageConfig {
                 name: "Typescript".into(),
                 path_suffixes: vec!["ts".to_string()],
+                brackets: language::BracketPairConfig {
+                    pairs: vec![language::BracketPair {
+                        start: "{".to_string(),
+                        end: "}".to_string(),
+                        close: true,
+                        newline: true,
+                    }],
+                    disabled_scopes_by_bracket_ix: Default::default(),
+                },
+                word_characters,
                 ..Default::default()
             },
             Some(tree_sitter_typescript::language_typescript()),
@@ -169,6 +183,23 @@ impl<'a> EditorLspTestContext<'a> {
                 ("{" @open "}" @close)
                 ("<" @open ">" @close)
                 ("\"" @open "\"" @close)"#})),
+            indents: Some(Cow::from(indoc! {r#"
+                [
+                    (call_expression)
+                    (assignment_expression)
+                    (member_expression)
+                    (lexical_declaration)
+                    (variable_declaration)
+                    (assignment_expression)
+                    (if_statement)
+                    (for_statement)
+                ] @indent
+
+                (_ "[" "]" @end) @indent
+                (_ "<" ">" @end) @indent
+                (_ "{" "}" @end) @indent
+                (_ "(" ")" @end) @indent
+                "#})),
             ..Default::default()
         })
         .expect("Could not parse queries");

crates/feedback/src/feedback_editor.rs

@@ -268,7 +268,7 @@ impl Item for FeedbackEditor {
         Some("Send Feedback".into())
     }
 
-    fn tab_content<T: View>(
+    fn tab_content<T: 'static>(
         &self,
         _: Option<usize>,
         style: &theme::Tab,

crates/gpui/Cargo.toml

@@ -39,6 +39,7 @@ pathfinder_color = "0.5"
 pathfinder_geometry = "0.5"
 postage.workspace = true
 rand.workspace = true
+refineable.workspace = true
 resvg = "0.14"
 schemars = "0.8"
 seahash = "4.1"
@@ -47,6 +48,7 @@ serde_derive.workspace = true
 serde_json.workspace = true
 smallvec.workspace = true
 smol.workspace = true
+taffy = { git = "https://github.com/DioxusLabs/taffy", rev = "dab541d6104d58e2e10ce90c4a1dad0b703160cd", features = ["flexbox"] }
 time.workspace = true
 tiny-skia = "0.5"
 usvg = { version = "0.14", features = [] }

crates/gpui/examples/text.rs

@@ -58,6 +58,7 @@ impl gpui::View for TextView {
                 font_family_id: family,
                 underline: Default::default(),
                 font_properties: Default::default(),
+                soft_wrap: false,
             },
         )
         .with_highlights(vec![(17..26, underline), (34..40, underline)])

crates/gpui/playground/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "playground"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[[bin]]
+name = "playground"
+path = "src/playground.rs"
+
+[dependencies]
+anyhow.workspace = true
+derive_more.workspace = true
+gpui = { path = ".." }
+log.workspace = true
+playground_macros = { path = "../playground_macros" }
+parking_lot.workspace = true
+refineable.workspace = true
+serde.workspace = true
+simplelog = "0.9"
+smallvec.workspace = true
+taffy = { git = "https://github.com/DioxusLabs/taffy", rev = "dab541d6104d58e2e10ce90c4a1dad0b703160cd", features = ["flexbox"] }
+util = { path = "../../util" }
+
+[dev-dependencies]
+gpui = { path = "..", features = ["test-support"] }

crates/gpui/playground/docs/thoughts.md

@@ -0,0 +1,72 @@
+Much of element styling is now handled by an external engine.
+
+
+How do I make an element hover.
+
+There's a hover style.
+
+Hoverable needs to wrap another element. That element can be styled.
+
+```rs
+struct Hoverable<E: Element> {
+
+}
+
+impl<V> Element<V> for Hoverable {
+
+}
+
+```
+
+
+
+```rs
+#[derive(Styled, Interactive)]
+pub struct Div {
+    declared_style: StyleRefinement,
+    interactions: Interactions
+}
+
+pub trait Styled {
+    fn declared_style(&mut self) -> &mut StyleRefinement;
+    fn compute_style(&mut self) -> Style {
+        Style::default().refine(self.declared_style())
+    }
+
+    // All the tailwind classes, modifying self.declared_style()
+}
+
+impl Style {
+    pub fn paint_background<V>(layout: Layout, cx: &mut PaintContext<V>);
+    pub fn paint_foreground<V>(layout: Layout, cx: &mut PaintContext<V>);
+}
+
+pub trait Interactive<V> {
+    fn interactions(&mut self) -> &mut Interactions<V>;
+
+    fn on_click(self, )
+}
+
+struct Interactions<V> {
+    click: SmallVec<[<Rc<dyn Fn(&mut V, &dyn Any, )>; 1]>,
+}
+
+
+```
+
+
+```rs
+
+
+trait Stylable {
+    type Style;
+
+    fn with_style(self, style: Self::Style) -> Self;
+}
+
+
+
+
+
+
+```

crates/gpui/playground/src/adapter.rs

@@ -0,0 +1,78 @@
+use crate::{layout_context::LayoutContext, paint_context::PaintContext};
+use gpui::{geometry::rect::RectF, LayoutEngine, LayoutId};
+use util::ResultExt;
+
+/// Makes a new, playground-style element into a legacy element.
+pub struct AdapterElement<V>(pub(crate) crate::element::AnyElement<V>);
+
+impl<V: 'static> gpui::Element<V> for AdapterElement<V> {
+    type LayoutState = Option<(LayoutEngine, LayoutId)>;
+    type PaintState = ();
+
+    fn layout(
+        &mut self,
+        constraint: gpui::SizeConstraint,
+        view: &mut V,
+        cx: &mut gpui::LayoutContext<V>,
+    ) -> (gpui::geometry::vector::Vector2F, Self::LayoutState) {
+        cx.push_layout_engine(LayoutEngine::new());
+
+        let size = constraint.max;
+        let mut cx = LayoutContext::new(cx);
+        let layout_id = self.0.layout(view, &mut cx).log_err();
+        if let Some(layout_id) = layout_id {
+            cx.layout_engine()
+                .unwrap()
+                .compute_layout(layout_id, constraint.max)
+                .log_err();
+        }
+
+        let layout_engine = cx.pop_layout_engine();
+        debug_assert!(layout_engine.is_some(),
+            "unexpected layout stack state. is there an unmatched pop_layout_engine in the called code?"
+        );
+
+        (constraint.max, layout_engine.zip(layout_id))
+    }
+
+    fn paint(
+        &mut self,
+        scene: &mut gpui::SceneBuilder,
+        bounds: RectF,
+        visible_bounds: RectF,
+        layout_data: &mut Option<(LayoutEngine, LayoutId)>,
+        view: &mut V,
+        legacy_cx: &mut gpui::PaintContext<V>,
+    ) -> Self::PaintState {
+        let (layout_engine, layout_id) = layout_data.take().unwrap();
+        legacy_cx.push_layout_engine(layout_engine);
+        let mut cx = PaintContext::new(legacy_cx, scene);
+        self.0.paint(view, &mut cx);
+        *layout_data = legacy_cx.pop_layout_engine().zip(Some(layout_id));
+        debug_assert!(layout_data.is_some());
+    }
+
+    fn rect_for_text_range(
+        &self,
+        range_utf16: std::ops::Range<usize>,
+        bounds: RectF,
+        visible_bounds: RectF,
+        layout: &Self::LayoutState,
+        paint: &Self::PaintState,
+        view: &V,
+        cx: &gpui::ViewContext<V>,
+    ) -> Option<RectF> {
+        todo!("implement before merging to main")
+    }
+
+    fn debug(
+        &self,
+        bounds: RectF,
+        layout: &Self::LayoutState,
+        paint: &Self::PaintState,
+        view: &V,
+        cx: &gpui::ViewContext<V>,
+    ) -> gpui::serde_json::Value {
+        todo!("implement before merging to main")
+    }
+}

crates/gpui/playground/src/color.rs

@@ -0,0 +1,276 @@
+#![allow(dead_code)]
+
+use std::{num::ParseIntError, ops::Range};
+
+use smallvec::SmallVec;
+
+pub fn rgb<C: From<Rgba>>(hex: u32) -> C {
+    let r = ((hex >> 16) & 0xFF) as f32 / 255.0;
+    let g = ((hex >> 8) & 0xFF) as f32 / 255.0;
+    let b = (hex & 0xFF) as f32 / 255.0;
+    Rgba { r, g, b, a: 1.0 }.into()
+}
+
+#[derive(Clone, Copy, Default, Debug)]
+pub struct Rgba {
+    pub r: f32,
+    pub g: f32,
+    pub b: f32,
+    pub a: f32,
+}
+
+pub trait Lerp {
+    fn lerp(&self, level: f32) -> Hsla;
+}
+
+impl Lerp for Range<Hsla> {
+    fn lerp(&self, level: f32) -> Hsla {
+        let level = level.clamp(0., 1.);
+        Hsla {
+            h: self.start.h + (level * (self.end.h - self.start.h)),
+            s: self.start.s + (level * (self.end.s - self.start.s)),
+            l: self.start.l + (level * (self.end.l - self.start.l)),
+            a: self.start.a + (level * (self.end.a - self.start.a)),
+        }
+    }
+}
+
+impl From<gpui::color::Color> for Rgba {
+    fn from(value: gpui::color::Color) -> Self {
+        Self {
+            r: value.0.r as f32 / 255.0,
+            g: value.0.g as f32 / 255.0,
+            b: value.0.b as f32 / 255.0,
+            a: value.0.a as f32 / 255.0,
+        }
+    }
+}
+
+impl From<Hsla> for Rgba {
+    fn from(color: Hsla) -> Self {
+        let h = color.h;
+        let s = color.s;
+        let l = color.l;
+
+        let c = (1.0 - (2.0 * l - 1.0).abs()) * s;
+        let x = c * (1.0 - ((h * 6.0) % 2.0 - 1.0).abs());
+        let m = l - c / 2.0;
+        let cm = c + m;
+        let xm = x + m;
+
+        let (r, g, b) = match (h * 6.0).floor() as i32 {
+            0 | 6 => (cm, xm, m),
+            1 => (xm, cm, m),
+            2 => (m, cm, xm),
+            3 => (m, xm, cm),
+            4 => (xm, m, cm),
+            _ => (cm, m, xm),
+        };
+
+        Rgba {
+            r,
+            g,
+            b,
+            a: color.a,
+        }
+    }
+}
+
+impl TryFrom<&'_ str> for Rgba {
+    type Error = ParseIntError;
+
+    fn try_from(value: &'_ str) -> Result<Self, Self::Error> {
+        let r = u8::from_str_radix(&value[1..3], 16)? as f32 / 255.0;
+        let g = u8::from_str_radix(&value[3..5], 16)? as f32 / 255.0;
+        let b = u8::from_str_radix(&value[5..7], 16)? as f32 / 255.0;
+        let a = if value.len() > 7 {
+            u8::from_str_radix(&value[7..9], 16)? as f32 / 255.0
+        } else {
+            1.0
+        };
+
+        Ok(Rgba { r, g, b, a })
+    }
+}
+
+impl Into<gpui::color::Color> for Rgba {
+    fn into(self) -> gpui::color::Color {
+        gpui::color::rgba(self.r, self.g, self.b, self.a)
+    }
+}
+
+#[derive(Default, Copy, Clone, Debug, PartialEq)]
+pub struct Hsla {
+    pub h: f32,
+    pub s: f32,
+    pub l: f32,
+    pub a: f32,
+}
+
+pub fn hsla(h: f32, s: f32, l: f32, a: f32) -> Hsla {
+    Hsla {
+        h: h.clamp(0., 1.),
+        s: s.clamp(0., 1.),
+        l: l.clamp(0., 1.),
+        a: a.clamp(0., 1.),
+    }
+}
+
+pub fn black() -> Hsla {
+    Hsla {
+        h: 0.,
+        s: 0.,
+        l: 0.,
+        a: 1.,
+    }
+}
+
+impl From<Rgba> for Hsla {
+    fn from(color: Rgba) -> Self {
+        let r = color.r;
+        let g = color.g;
+        let b = color.b;
+
+        let max = r.max(g.max(b));
+        let min = r.min(g.min(b));
+        let delta = max - min;
+
+        let l = (max + min) / 2.0;
+        let s = if l == 0.0 || l == 1.0 {
+            0.0
+        } else if l < 0.5 {
+            delta / (2.0 * l)
+        } else {
+            delta / (2.0 - 2.0 * l)
+        };
+
+        let h = if delta == 0.0 {
+            0.0
+        } else if max == r {
+            ((g - b) / delta).rem_euclid(6.0) / 6.0
+        } else if max == g {
+            ((b - r) / delta + 2.0) / 6.0
+        } else {
+            ((r - g) / delta + 4.0) / 6.0
+        };
+
+        Hsla {
+            h,
+            s,
+            l,
+            a: color.a,
+        }
+    }
+}
+
+impl Hsla {
+    /// Scales the saturation and lightness by the given values, clamping at 1.0.
+    pub fn scale_sl(mut self, s: f32, l: f32) -> Self {
+        self.s = (self.s * s).clamp(0., 1.);
+        self.l = (self.l * l).clamp(0., 1.);
+        self
+    }
+
+    /// Increases the saturation of the color by a certain amount, with a max
+    /// value of 1.0.
+    pub fn saturate(mut self, amount: f32) -> Self {
+        self.s += amount;
+        self.s = self.s.clamp(0.0, 1.0);
+        self
+    }
+
+    /// Decreases the saturation of the color by a certain amount, with a min
+    /// value of 0.0.
+    pub fn desaturate(mut self, amount: f32) -> Self {
+        self.s -= amount;
+        self.s = self.s.max(0.0);
+        if self.s < 0.0 {
+            self.s = 0.0;
+        }
+        self
+    }
+
+    /// Brightens the color by increasing the lightness by a certain amount,
+    /// with a max value of 1.0.
+    pub fn brighten(mut self, amount: f32) -> Self {
+        self.l += amount;
+        self.l = self.l.clamp(0.0, 1.0);
+        self
+    }
+
+    /// Darkens the color by decreasing the lightness by a certain amount,
+    /// with a max value of 0.0.
+    pub fn darken(mut self, amount: f32) -> Self {
+        self.l -= amount;
+        self.l = self.l.clamp(0.0, 1.0);
+        self
+    }
+}
+
+impl From<gpui::color::Color> for Hsla {
+    fn from(value: gpui::color::Color) -> Self {
+        Rgba::from(value).into()
+    }
+}
+
+impl Into<gpui::color::Color> for Hsla {
+    fn into(self) -> gpui::color::Color {
+        Rgba::from(self).into()
+    }
+}
+
+pub struct ColorScale {
+    colors: SmallVec<[Hsla; 2]>,
+    positions: SmallVec<[f32; 2]>,
+}
+
+pub fn scale<I, C>(colors: I) -> ColorScale
+where
+    I: IntoIterator<Item = C>,
+    C: Into<Hsla>,
+{
+    let mut scale = ColorScale {
+        colors: colors.into_iter().map(Into::into).collect(),
+        positions: SmallVec::new(),
+    };
+    let num_colors: f32 = scale.colors.len() as f32 - 1.0;
+    scale.positions = (0..scale.colors.len())
+        .map(|i| i as f32 / num_colors)
+        .collect();
+    scale
+}
+
+impl ColorScale {
+    fn at(&self, t: f32) -> Hsla {
+        // Ensure that the input is within [0.0, 1.0]
+        debug_assert!(
+            0.0 <= t && t <= 1.0,
+            "t value {} is out of range. Expected value in range 0.0 to 1.0",
+            t
+        );
+
+        let position = match self
+            .positions
+            .binary_search_by(|a| a.partial_cmp(&t).unwrap())
+        {
+            Ok(index) | Err(index) => index,
+        };
+        let lower_bound = position.saturating_sub(1);
+        let upper_bound = position.min(self.colors.len() - 1);
+        let lower_color = &self.colors[lower_bound];
+        let upper_color = &self.colors[upper_bound];
+
+        match upper_bound.checked_sub(lower_bound) {
+            Some(0) | None => *lower_color,
+            Some(_) => {
+                let interval_t = (t - self.positions[lower_bound])
+                    / (self.positions[upper_bound] - self.positions[lower_bound]);
+                let h = lower_color.h + interval_t * (upper_color.h - lower_color.h);
+                let s = lower_color.s + interval_t * (upper_color.s - lower_color.s);
+                let l = lower_color.l + interval_t * (upper_color.l - lower_color.l);
+                let a = lower_color.a + interval_t * (upper_color.a - lower_color.a);
+                Hsla { h, s, l, a }
+            }
+        }
+    }
+}

crates/gpui/playground/src/components.rs

@@ -0,0 +1,100 @@
+use crate::{
+    div::div,
+    element::{Element, ParentElement},
+    style::StyleHelpers,
+    text::ArcCow,
+    themes::rose_pine,
+};
+use gpui::ViewContext;
+use playground_macros::Element;
+use std::{marker::PhantomData, rc::Rc};
+
+struct ButtonHandlers<V, D> {
+    click: Option<Rc<dyn Fn(&mut V, &D, &mut ViewContext<V>)>>,
+}
+
+impl<V, D> Default for ButtonHandlers<V, D> {
+    fn default() -> Self {
+        Self { click: None }
+    }
+}
+
+use crate as playground;
+#[derive(Element)]
+pub struct Button<V: 'static, D: 'static> {
+    handlers: ButtonHandlers<V, D>,
+    label: Option<ArcCow<'static, str>>,
+    icon: Option<ArcCow<'static, str>>,
+    data: Rc<D>,
+    view_type: PhantomData<V>,
+}
+
+// Impl block for buttons without data.
+// See below for an impl block for any button.
+impl<V: 'static> Button<V, ()> {
+    fn new() -> Self {
+        Self {
+            handlers: ButtonHandlers::default(),
+            label: None,
+            icon: None,
+            data: Rc::new(()),
+            view_type: PhantomData,
+        }
+    }
+
+    pub fn data<D: 'static>(self, data: D) -> Button<V, D> {
+        Button {
+            handlers: ButtonHandlers::default(),
+            label: self.label,
+            icon: self.icon,
+            data: Rc::new(data),
+            view_type: PhantomData,
+        }
+    }
+}
+
+// Impl block for *any* button.
+impl<V: 'static, D: 'static> Button<V, D> {
+    pub fn label(mut self, label: impl Into<ArcCow<'static, str>>) -> Self {
+        self.label = Some(label.into());
+        self
+    }
+
+    pub fn icon(mut self, icon: impl Into<ArcCow<'static, str>>) -> Self {
+        self.icon = Some(icon.into());
+        self
+    }
+
+    // pub fn click(self, handler: impl Fn(&mut V, &D, &mut ViewContext<V>) + 'static) -> Self {
+    //     let data = self.data.clone();
+    //     Self::click(self, MouseButton::Left, move |view, _, cx| {
+    //         handler(view, data.as_ref(), cx);
+    //     })
+    // }
+}
+
+pub fn button<V>() -> Button<V, ()> {
+    Button::new()
+}
+
+impl<V: 'static, D: 'static> Button<V, D> {
+    fn render(&mut self, view: &mut V, cx: &mut ViewContext<V>) -> impl Element<V> {
+        // TODO: Drive theme from the context
+        let button = div()
+            .fill(rose_pine::dawn().error(0.5))
+            .h_4()
+            .children(self.label.clone());
+
+        button
+
+        // TODO: Event handling
+        // if let Some(handler) = self.handlers.click.clone() {
+        //     let data = self.data.clone();
+        //     // button.mouse_down(MouseButton::Left, move |view, event, cx| {
+        //     //     handler(view, data.as_ref(), cx)
+        //     // })
+        // } else {
+        //     button
+        // }
+    }
+}

crates/gpui/playground/src/div.rs

@@ -0,0 +1,108 @@
+use crate::{
+    element::{AnyElement, Element, Layout, ParentElement},
+    interactive::{InteractionHandlers, Interactive},
+    layout_context::LayoutContext,
+    paint_context::PaintContext,
+    style::{Style, StyleHelpers, StyleRefinement, Styleable},
+};
+use anyhow::Result;
+use gpui::LayoutId;
+use smallvec::SmallVec;
+
+pub struct Div<V: 'static> {
+    style: StyleRefinement,
+    handlers: InteractionHandlers<V>,
+    children: SmallVec<[AnyElement<V>; 2]>,
+}
+
+pub fn div<V>() -> Div<V> {
+    Div {
+        style: Default::default(),
+        handlers: Default::default(),
+        children: Default::default(),
+    }
+}
+
+impl<V: 'static> Element<V> for Div<V> {
+    type Layout = ();
+
+    fn layout(&mut self, view: &mut V, cx: &mut LayoutContext<V>) -> Result<Layout<V, ()>>
+    where
+        Self: Sized,
+    {
+        let children = self
+            .children
+            .iter_mut()
+            .map(|child| child.layout(view, cx))
+            .collect::<Result<Vec<LayoutId>>>()?;
+
+        cx.add_layout_node(self.style(), (), children)
+    }
+
+    fn paint(&mut self, view: &mut V, layout: &mut Layout<V, ()>, cx: &mut PaintContext<V>)
+    where
+        Self: Sized,
+    {
+        let style = self.style();
+
+        style.paint_background::<V, Self>(layout, cx);
+        for child in &mut self.children {
+            child.paint(view, cx);
+        }
+    }
+}
+
+impl<V> Styleable for Div<V> {
+    type Style = Style;
+
+    fn declared_style(&mut self) -> &mut StyleRefinement {
+        &mut self.style
+    }
+}
+
+impl<V> StyleHelpers for Div<V> {}
+
+impl<V> Interactive<V> for Div<V> {
+    fn interaction_handlers(&mut self) -> &mut InteractionHandlers<V> {
+        &mut self.handlers
+    }
+}
+
+impl<V: 'static> ParentElement<V> for Div<V> {
+    fn children_mut(&mut self) -> &mut SmallVec<[AnyElement<V>; 2]> {
+        &mut self.children
+    }
+}
+
+#[test]
+fn test() {
+    // let elt = div().w_auto();
+}
+
+// trait Element<V: 'static> {
+//     type Style;
+
+//     fn layout()
+// }
+
+// trait Stylable<V: 'static>: Element<V> {
+//     type Style;
+
+//     fn with_style(self, style: Self::Style) -> Self;
+// }
+
+// pub struct HoverStyle<S> {
+//     default: S,
+//     hovered: S,
+// }
+
+// struct Hover<V: 'static, C: Stylable<V>> {
+//     child: C,
+//     style: HoverStyle<C::Style>,
+// }
+
+// impl<V: 'static, C: Stylable<V>> Hover<V, C> {
+//     fn new(child: C, style: HoverStyle<C::Style>) -> Self {
+//         Self { child, style }
+//     }
+// }

crates/gpui/playground/src/element.rs

@@ -0,0 +1,158 @@
+use anyhow::Result;
+use derive_more::{Deref, DerefMut};
+use gpui::{geometry::rect::RectF, EngineLayout};
+use smallvec::SmallVec;
+use std::marker::PhantomData;
+use util::ResultExt;
+
+pub use crate::layout_context::LayoutContext;
+pub use crate::paint_context::PaintContext;
+
+type LayoutId = gpui::LayoutId;
+
+pub trait Element<V: 'static>: 'static {
+    type Layout;
+
+    fn layout(
+        &mut self,
+        view: &mut V,
+        cx: &mut LayoutContext<V>,
+    ) -> Result<Layout<V, Self::Layout>>
+    where
+        Self: Sized;
+
+    fn paint(
+        &mut self,
+        view: &mut V,
+        layout: &mut Layout<V, Self::Layout>,
+        cx: &mut PaintContext<V>,
+    ) where
+        Self: Sized;
+
+    fn into_any(self) -> AnyElement<V>
+    where
+        Self: 'static + Sized,
+    {
+        AnyElement(Box::new(ElementState {
+            element: self,
+            layout: None,
+        }))
+    }
+}
+
+/// Used to make ElementState<V, E> into a trait object, so we can wrap it in AnyElement<V>.
+trait ElementStateObject<V> {
+    fn layout(&mut self, view: &mut V, cx: &mut LayoutContext<V>) -> Result<LayoutId>;
+    fn paint(&mut self, view: &mut V, cx: &mut PaintContext<V>);
+}
+
+/// A wrapper around an element that stores its layout state.
+struct ElementState<V: 'static, E: Element<V>> {
+    element: E,
+    layout: Option<Layout<V, E::Layout>>,
+}
+
+/// We blanket-implement the object-safe ElementStateObject interface to make ElementStates into trait objects
+impl<V, E: Element<V>> ElementStateObject<V> for ElementState<V, E> {
+    fn layout(&mut self, view: &mut V, cx: &mut LayoutContext<V>) -> Result<LayoutId> {
+        let layout = self.element.layout(view, cx)?;
+        let layout_id = layout.id;
+        self.layout = Some(layout);
+        Ok(layout_id)
+    }
+
+    fn paint(&mut self, view: &mut V, cx: &mut PaintContext<V>) {
+        let layout = self.layout.as_mut().expect("paint called before layout");
+        if layout.engine_layout.is_none() {
+            layout.engine_layout = cx.computed_layout(layout.id).log_err()
+        }
+        self.element.paint(view, layout, cx)
+    }
+}
+
+/// A dynamic element.
+pub struct AnyElement<V>(Box<dyn ElementStateObject<V>>);
+
+impl<V> AnyElement<V> {
+    pub fn layout(&mut self, view: &mut V, cx: &mut LayoutContext<V>) -> Result<LayoutId> {
+        self.0.layout(view, cx)
+    }
+
+    pub fn paint(&mut self, view: &mut V, cx: &mut PaintContext<V>) {
+        self.0.paint(view, cx)
+    }
+}
+
+#[derive(Deref, DerefMut)]
+pub struct Layout<V, D> {
+    id: LayoutId,
+    engine_layout: Option<EngineLayout>,
+    #[deref]
+    #[deref_mut]
+    element_data: D,
+    view_type: PhantomData<V>,
+}
+
+impl<V: 'static, D> Layout<V, D> {
+    pub fn new(id: LayoutId, element_data: D) -> Self {
+        Self {
+            id,
+            engine_layout: None,
+            element_data: element_data,
+            view_type: PhantomData,
+        }
+    }
+
+    pub fn bounds(&mut self, cx: &mut PaintContext<V>) -> RectF {
+        self.engine_layout(cx).bounds
+    }
+
+    pub fn order(&mut self, cx: &mut PaintContext<V>) -> u32 {
+        self.engine_layout(cx).order
+    }
+
+    fn engine_layout(&mut self, cx: &mut PaintContext<'_, '_, '_, '_, V>) -> &mut EngineLayout {
+        self.engine_layout
+            .get_or_insert_with(|| cx.computed_layout(self.id).log_err().unwrap_or_default())
+    }
+}
+
+impl<V: 'static> Layout<V, Option<AnyElement<V>>> {
+    pub fn paint(&mut self, view: &mut V, cx: &mut PaintContext<V>) {
+        let mut element = self.element_data.take().unwrap();
+        element.paint(view, cx);
+        self.element_data = Some(element);
+    }
+}
+
+pub trait ParentElement<V: 'static> {
+    fn children_mut(&mut self) -> &mut SmallVec<[AnyElement<V>; 2]>;
+
+    fn child(mut self, child: impl IntoElement<V>) -> Self
+    where
+        Self: Sized,
+    {
+        self.children_mut().push(child.into_element().into_any());
+        self
+    }
+
+    fn children<I, E>(mut self, children: I) -> Self
+    where
+        I: IntoIterator<Item = E>,
+        E: IntoElement<V>,
+        Self: Sized,
+    {
+        self.children_mut().extend(
+            children
+                .into_iter()
+                .map(|child| child.into_element().into_any()),
+        );
+        self
+    }
+}
+
+pub trait IntoElement<V: 'static> {
+    type Element: Element<V>;
+
+    fn into_element(self) -> Self::Element;
+}

crates/gpui/playground/src/hoverable.rs

@@ -0,0 +1,76 @@
+use crate::{
+    element::{Element, Layout},
+    layout_context::LayoutContext,
+    paint_context::PaintContext,
+    style::{StyleRefinement, Styleable},
+};
+use anyhow::Result;
+use gpui::platform::MouseMovedEvent;
+use refineable::Refineable;
+use std::{cell::Cell, marker::PhantomData};
+
+pub struct Hoverable<V: 'static, E: Element<V> + Styleable> {
+    hovered: Cell<bool>,
+    child_style: StyleRefinement,
+    hovered_style: StyleRefinement,
+    child: E,
+    view_type: PhantomData<V>,
+}
+
+pub fn hoverable<V, E: Element<V> + Styleable>(mut child: E) -> Hoverable<V, E> {
+    Hoverable {
+        hovered: Cell::new(false),
+        child_style: child.declared_style().clone(),
+        hovered_style: Default::default(),
+        child,
+        view_type: PhantomData,
+    }
+}
+
+impl<V, E: Element<V> + Styleable> Styleable for Hoverable<V, E> {
+    type Style = E::Style;
+
+    fn declared_style(&mut self) -> &mut crate::style::StyleRefinement {
+        self.child.declared_style()
+    }
+}
+
+impl<V: 'static, E: Element<V> + Styleable> Element<V> for Hoverable<V, E> {
+    type Layout = E::Layout;
+
+    fn layout(&mut self, view: &mut V, cx: &mut LayoutContext<V>) -> Result<Layout<V, Self::Layout>>
+    where
+        Self: Sized,
+    {
+        self.child.layout(view, cx)
+    }
+
+    fn paint(
+        &mut self,
+        view: &mut V,
+        layout: &mut Layout<V, Self::Layout>,
+        cx: &mut PaintContext<V>,
+    ) where
+        Self: Sized,
+    {
+        if self.hovered.get() {
+            // If hovered, refine the child's style with this element's style.
+            self.child.declared_style().refine(&self.hovered_style);
+        } else {
+            // Otherwise, set the child's style back to its original style.
+            *self.child.declared_style() = self.child_style.clone();
+        }
+
+        let bounds = layout.bounds(cx);
+        let order = layout.order(cx);
+        self.hovered.set(bounds.contains_point(cx.mouse_position()));
+        let was_hovered = self.hovered.clone();
+        cx.on_event(order, move |view, event: &MouseMovedEvent, cx| {
+            let is_hovered = bounds.contains_point(event.position);
+            if is_hovered != was_hovered.get() {
+                was_hovered.set(is_hovered);
+                cx.repaint();
+            }
+        });
+    }
+}

crates/gpui/playground/src/interactive.rs

@@ -0,0 +1,34 @@
+use gpui::{platform::MouseMovedEvent, EventContext};
+use smallvec::SmallVec;
+use std::rc::Rc;
+
+pub trait Interactive<V: 'static> {
+    fn interaction_handlers(&mut self) -> &mut InteractionHandlers<V>;
+
+    fn on_mouse_move<H>(mut self, handler: H) -> Self
+    where
+        H: 'static + Fn(&mut V, &MouseMovedEvent, bool, &mut EventContext<V>),
+        Self: Sized,
+    {
+        self.interaction_handlers()
+            .mouse_moved
+            .push(Rc::new(move |view, event, hit_test, cx| {
+                handler(view, event, hit_test, cx);
+                cx.bubble
+            }));
+        self
+    }
+}
+
+pub struct InteractionHandlers<V: 'static> {
+    mouse_moved:
+        SmallVec<[Rc<dyn Fn(&mut V, &MouseMovedEvent, bool, &mut EventContext<V>) -> bool>; 2]>,
+}
+
+impl<V> Default for InteractionHandlers<V> {
+    fn default() -> Self {
+        Self {
+            mouse_moved: Default::default(),
+        }
+    }
+}

crates/gpui/playground/src/layout_context.rs

@@ -0,0 +1,54 @@
+use anyhow::{anyhow, Result};
+use derive_more::{Deref, DerefMut};
+pub use gpui::LayoutContext as LegacyLayoutContext;
+use gpui::{RenderContext, ViewContext};
+pub use taffy::tree::NodeId;
+
+use crate::{element::Layout, style::Style};
+
+#[derive(Deref, DerefMut)]
+pub struct LayoutContext<'a, 'b, 'c, 'd, V> {
+    #[deref]
+    #[deref_mut]
+    pub(crate) legacy_cx: &'d mut LegacyLayoutContext<'a, 'b, 'c, V>,
+}
+
+impl<'a, 'b, V> RenderContext<'a, 'b, V> for LayoutContext<'a, 'b, '_, '_, V> {
+    fn text_style(&self) -> gpui::fonts::TextStyle {
+        self.legacy_cx.text_style()
+    }
+
+    fn push_text_style(&mut self, style: gpui::fonts::TextStyle) {
+        self.legacy_cx.push_text_style(style)
+    }
+
+    fn pop_text_style(&mut self) {
+        self.legacy_cx.pop_text_style()
+    }
+
+    fn as_view_context(&mut self) -> &mut ViewContext<'a, 'b, V> {
+        &mut self.view_context
+    }
+}
+
+impl<'a, 'b, 'c, 'd, V: 'static> LayoutContext<'a, 'b, 'c, 'd, V> {
+    pub fn new(legacy_cx: &'d mut LegacyLayoutContext<'a, 'b, 'c, V>) -> Self {
+        Self { legacy_cx }
+    }
+
+    pub fn add_layout_node<D>(
+        &mut self,
+        style: Style,
+        element_data: D,
+        children: impl IntoIterator<Item = NodeId>,
+    ) -> Result<Layout<V, D>> {
+        let rem_size = self.rem_pixels();
+        let id = self
+            .legacy_cx
+            .layout_engine()
+            .ok_or_else(|| anyhow!("no layout engine"))?
+            .add_node(style.to_taffy(rem_size), children)?;
+
+        Ok(Layout::new(id, element_data))
+    }
+}

crates/gpui/playground/src/paint_context.rs

@@ -0,0 +1,71 @@
+use anyhow::{anyhow, Result};
+use derive_more::{Deref, DerefMut};
+use gpui::{scene::EventHandler, EngineLayout, EventContext, LayoutId, RenderContext, ViewContext};
+pub use gpui::{LayoutContext, PaintContext as LegacyPaintContext};
+use std::{any::TypeId, rc::Rc};
+pub use taffy::tree::NodeId;
+
+#[derive(Deref, DerefMut)]
+pub struct PaintContext<'a, 'b, 'c, 'd, V> {
+    #[deref]
+    #[deref_mut]
+    pub(crate) legacy_cx: &'d mut LegacyPaintContext<'a, 'b, 'c, V>,
+    pub(crate) scene: &'d mut gpui::SceneBuilder,
+}
+
+impl<'a, 'b, V> RenderContext<'a, 'b, V> for PaintContext<'a, 'b, '_, '_, V> {
+    fn text_style(&self) -> gpui::fonts::TextStyle {
+        self.legacy_cx.text_style()
+    }
+
+    fn push_text_style(&mut self, style: gpui::fonts::TextStyle) {
+        self.legacy_cx.push_text_style(style)
+    }
+
+    fn pop_text_style(&mut self) {
+        self.legacy_cx.pop_text_style()
+    }
+
+    fn as_view_context(&mut self) -> &mut ViewContext<'a, 'b, V> {
+        &mut self.view_context
+    }
+}
+
+impl<'a, 'b, 'c, 'd, V: 'static> PaintContext<'a, 'b, 'c, 'd, V> {
+    pub fn new(
+        legacy_cx: &'d mut LegacyPaintContext<'a, 'b, 'c, V>,
+        scene: &'d mut gpui::SceneBuilder,
+    ) -> Self {
+        Self { legacy_cx, scene }
+    }
+
+    pub fn on_event<E: 'static>(
+        &mut self,
+        order: u32,
+        handler: impl Fn(&mut V, &E, &mut ViewContext<V>) + 'static,
+    ) {
+        let view = self.weak_handle();
+
+        self.scene.event_handlers.push(EventHandler {
+            order,
+            handler: Rc::new(move |event, window_cx| {
+                if let Some(view) = view.upgrade(window_cx) {
+                    view.update(window_cx, |view, view_cx| {
+                        let mut event_cx = EventContext::new(view_cx);
+                        handler(view, event.downcast_ref().unwrap(), &mut event_cx);
+                        event_cx.bubble
+                    })
+                } else {
+                    true
+                }
+            }),
+            event_type: TypeId::of::<E>(),
+        })
+    }
+
+    pub(crate) fn computed_layout(&mut self, layout_id: LayoutId) -> Result<EngineLayout> {
+        self.layout_engine()
+            .ok_or_else(|| anyhow!("no layout engine present"))?
+            .computed_layout(layout_id)
+    }
+}

crates/gpui/playground/src/playground.rs

@@ -0,0 +1,83 @@
+#![allow(dead_code, unused_variables)]
+use crate::{color::black, style::StyleHelpers};
+use element::Element;
+use gpui::{
+    geometry::{rect::RectF, vector::vec2f},
+    platform::WindowOptions,
+};
+use log::LevelFilter;
+use simplelog::SimpleLogger;
+use themes::{rose_pine, ThemeColors};
+use view::view;
+
+mod adapter;
+mod color;
+mod components;
+mod div;
+mod element;
+mod hoverable;
+mod interactive;
+mod layout_context;
+mod paint_context;
+mod style;
+mod text;
+mod themes;
+mod view;
+
+fn main() {
+    SimpleLogger::init(LevelFilter::Info, Default::default()).expect("could not initialize logger");
+
+    gpui::App::new(()).unwrap().run(|cx| {
+        cx.add_window(
+            WindowOptions {
+                bounds: gpui::platform::WindowBounds::Fixed(RectF::new(
+                    vec2f(0., 0.),
+                    vec2f(400., 300.),
+                )),
+                center: true,
+                ..Default::default()
+            },
+            |_| view(|_| playground(&rose_pine::moon())),
+        );
+        cx.platform().activate(true);
+    });
+}
+
+fn playground<V: 'static>(theme: &ThemeColors) -> impl Element<V> {
+    use div::div;
+
+    div()
+        .text_color(black())
+        .h_full()
+        .w_1_2()
+        .fill(theme.success(0.5))
+    // .hover()
+    // .fill(theme.error(0.5))
+    // .child(button().label("Hello").click(|_, _, _| println!("click!")))
+}
+
+//     todo!()
+//     // column()
+//     // .size(auto())
+//     // .fill(theme.base(0.5))
+//     // .text_color(theme.text(0.5))
+//     // .child(title_bar(theme))
+//     // .child(stage(theme))
+//     // .child(status_bar(theme))
+// }
+
+// fn title_bar<V: 'static>(theme: &ThemeColors) -> impl Element<V> {
+//     row()
+//         .fill(theme.base(0.2))
+//         .justify(0.)
+//         .width(auto())
+//         .child(text("Zed Playground"))
+// }
+
+// fn stage<V: 'static>(theme: &ThemeColors) -> impl Element<V> {
+//     row().fill(theme.surface(0.9))
+// }
+
+// fn status_bar<V: 'static>(theme: &ThemeColors) -> impl Element<V> {
+//     row().fill(theme.surface(0.1))
+// }

crates/gpui/playground/src/style.rs

@@ -0,0 +1,286 @@
+use crate::{
+    color::Hsla,
+    element::{Element, Layout},
+    paint_context::PaintContext,
+};
+use gpui::{
+    fonts::TextStyleRefinement,
+    geometry::{
+        AbsoluteLength, DefiniteLength, Edges, EdgesRefinement, Length, Point, PointRefinement,
+        Size, SizeRefinement,
+    },
+};
+use playground_macros::styleable_helpers;
+use refineable::Refineable;
+pub use taffy::style::{
+    AlignContent, AlignItems, AlignSelf, Display, FlexDirection, FlexWrap, JustifyContent,
+    Overflow, Position,
+};
+
+#[derive(Clone, Refineable)]
+pub struct Style {
+    /// What layout strategy should be used?
+    pub display: Display,
+
+    // Overflow properties
+    /// How children overflowing their container should affect layout
+    #[refineable]
+    pub overflow: Point<Overflow>,
+    /// How much space (in points) should be reserved for the scrollbars of `Overflow::Scroll` and `Overflow::Auto` nodes.
+    pub scrollbar_width: f32,
+
+    // Position properties
+    /// What should the `position` value of this struct use as a base offset?
+    pub position: Position,
+    /// How should the position of this element be tweaked relative to the layout defined?
+    #[refineable]
+    pub inset: Edges<Length>,
+
+    // Size properies
+    /// Sets the initial size of the item
+    #[refineable]
+    pub size: Size<Length>,
+    /// Controls the minimum size of the item
+    #[refineable]
+    pub min_size: Size<Length>,
+    /// Controls the maximum size of the item
+    #[refineable]
+    pub max_size: Size<Length>,
+    /// Sets the preferred aspect ratio for the item. The ratio is calculated as width divided by height.
+    pub aspect_ratio: Option<f32>,
+
+    // Spacing Properties
+    /// How large should the margin be on each side?
+    #[refineable]
+    pub margin: Edges<Length>,
+    /// How large should the padding be on each side?
+    #[refineable]
+    pub padding: Edges<DefiniteLength>,
+    /// How large should the border be on each side?
+    #[refineable]
+    pub border: Edges<DefiniteLength>,
+
+    // Alignment properties
+    /// How this node's children aligned in the cross/block axis?
+    pub align_items: Option<AlignItems>,
+    /// How this node should be aligned in the cross/block axis. Falls back to the parents [`AlignItems`] if not set
+    pub align_self: Option<AlignSelf>,
+    /// How should content contained within this item be aligned in the cross/block axis
+    pub align_content: Option<AlignContent>,
+    /// How should contained within this item be aligned in the main/inline axis
+    pub justify_content: Option<JustifyContent>,
+    /// How large should the gaps between items in a flex container be?
+    #[refineable]
+    pub gap: Size<DefiniteLength>,
+
+    // Flexbox properies
+    /// Which direction does the main axis flow in?
+    pub flex_direction: FlexDirection,
+    /// Should elements wrap, or stay in a single line?
+    pub flex_wrap: FlexWrap,
+    /// Sets the initial main axis size of the item
+    pub flex_basis: Length,
+    /// The relative rate at which this item grows when it is expanding to fill space, 0.0 is the default value, and this value must be positive.
+    pub flex_grow: f32,
+    /// The relative rate at which this item shrinks when it is contracting to fit into space, 1.0 is the default value, and this value must be positive.
+    pub flex_shrink: f32,
+
+    /// The fill color of this element
+    pub fill: Option<Fill>,
+    /// The radius of the corners of this element
+    #[refineable]
+    pub corner_radii: CornerRadii,
+    /// The color of text within this element. Cascades to children unless overridden.
+    pub text_color: Option<Hsla>,
+}
+
+impl Style {
+    pub fn to_taffy(&self, rem_size: f32) -> taffy::style::Style {
+        taffy::style::Style {
+            display: self.display,
+            overflow: self.overflow.clone().into(),
+            scrollbar_width: self.scrollbar_width,
+            position: self.position,
+            inset: self.inset.to_taffy(rem_size),
+            size: self.size.to_taffy(rem_size),
+            min_size: self.min_size.to_taffy(rem_size),
+            max_size: self.max_size.to_taffy(rem_size),
+            aspect_ratio: self.aspect_ratio,
+            margin: self.margin.to_taffy(rem_size),
+            padding: self.padding.to_taffy(rem_size),
+            border: self.border.to_taffy(rem_size),
+            align_items: self.align_items,
+            align_self: self.align_self,
+            align_content: self.align_content,
+            justify_content: self.justify_content,
+            gap: self.gap.to_taffy(rem_size),
+            flex_direction: self.flex_direction,
+            flex_wrap: self.flex_wrap,
+            flex_basis: self.flex_basis.to_taffy(rem_size).into(),
+            flex_grow: self.flex_grow,
+            flex_shrink: self.flex_shrink,
+            ..Default::default() // Ignore grid properties for now
+        }
+    }
+
+    /// Paints the background of an element styled with this style.
+    /// Return the bounds in which to paint the content.
+    pub fn paint_background<V: 'static, E: Element<V>>(
+        &self,
+        layout: &mut Layout<V, E::Layout>,
+        cx: &mut PaintContext<V>,
+    ) {
+        let bounds = layout.bounds(cx);
+        let rem_size = cx.rem_pixels();
+        if let Some(color) = self.fill.as_ref().and_then(Fill::color) {
+            cx.scene.push_quad(gpui::Quad {
+                bounds,
+                background: Some(color.into()),
+                corner_radii: self.corner_radii.to_gpui(rem_size),
+                border: Default::default(),
+            });
+        }
+    }
+}
+
+impl Default for Style {
+    fn default() -> Self {
+        Style {
+            display: Display::DEFAULT,
+            overflow: Point {
+                x: Overflow::Visible,
+                y: Overflow::Visible,
+            },
+            scrollbar_width: 0.0,
+            position: Position::Relative,
+            inset: Edges::auto(),
+            margin: Edges::<Length>::zero(),
+            padding: Edges::<DefiniteLength>::zero(),
+            border: Edges::<DefiniteLength>::zero(),
+            size: Size::auto(),
+            min_size: Size::auto(),
+            max_size: Size::auto(),
+            aspect_ratio: None,
+            gap: Size::zero(),
+            // Aligment
+            align_items: None,
+            align_self: None,
+            align_content: None,
+            justify_content: None,
+            // Flexbox
+            flex_direction: FlexDirection::Row,
+            flex_wrap: FlexWrap::NoWrap,
+            flex_grow: 0.0,
+            flex_shrink: 1.0,
+            flex_basis: Length::Auto,
+            fill: None,
+            text_color: None,
+            corner_radii: CornerRadii::default(),
+        }
+    }
+}
+
+impl StyleRefinement {
+    pub fn text_style(&self) -> Option<TextStyleRefinement> {
+        self.text_color.map(|color| TextStyleRefinement {
+            color: Some(color.into()),
+            ..Default::default()
+        })
+    }
+}
+
+pub struct OptionalTextStyle {
+    color: Option<Hsla>,
+}
+
+impl OptionalTextStyle {
+    pub fn apply(&self, style: &mut gpui::fonts::TextStyle) {
+        if let Some(color) = self.color {
+            style.color = color.into();
+        }
+    }
+}
+
+#[derive(Clone)]
+pub enum Fill {
+    Color(Hsla),
+}
+
+impl Fill {
+    pub fn color(&self) -> Option<Hsla> {
+        match self {
+            Fill::Color(color) => Some(*color),
+        }
+    }
+}
+
+impl Default for Fill {
+    fn default() -> Self {
+        Self::Color(Hsla::default())
+    }
+}
+
+impl From<Hsla> for Fill {
+    fn from(color: Hsla) -> Self {
+        Self::Color(color)
+    }
+}
+
+#[derive(Clone, Refineable, Default)]
+pub struct CornerRadii {
+    top_left: AbsoluteLength,
+    top_right: AbsoluteLength,
+    bottom_left: AbsoluteLength,
+    bottom_right: AbsoluteLength,
+}
+
+impl CornerRadii {
+    pub fn to_gpui(&self, rem_size: f32) -> gpui::scene::CornerRadii {
+        gpui::scene::CornerRadii {
+            top_left: self.top_left.to_pixels(rem_size),
+            top_right: self.top_right.to_pixels(rem_size),
+            bottom_left: self.bottom_left.to_pixels(rem_size),
+            bottom_right: self.bottom_right.to_pixels(rem_size),
+        }
+    }
+}
+
+pub trait Styleable {
+    type Style: refineable::Refineable;
+
+    fn declared_style(&mut self) -> &mut playground::style::StyleRefinement;
+
+    fn style(&mut self) -> playground::style::Style {
+        let mut style = playground::style::Style::default();
+        style.refine(self.declared_style());
+        style
+    }
+}
+
+// Helpers methods that take and return mut self. This includes tailwind style methods for standard sizes etc.
+//
+// Example:
+// // Sets the padding to 0.5rem, just like class="p-2" in Tailwind.
+// fn p_2(mut self) -> Self where Self: Sized;
+use crate as playground; // Macro invocation references this crate as playground.
+pub trait StyleHelpers: Styleable<Style = Style> {
+    styleable_helpers!();
+
+    fn fill<F>(mut self, fill: F) -> Self
+    where
+        F: Into<Fill>,
+        Self: Sized,
+    {
+        self.declared_style().fill = Some(fill.into());
+        self
+    }
+
+    fn text_color<C>(mut self, color: C) -> Self
+    where
+        C: Into<Hsla>,
+        Self: Sized,
+    {
+        self.declared_style().text_color = Some(color.into());
+        self
+    }
+}

crates/gpui/playground/src/text.rs

@@ -0,0 +1,151 @@
+use crate::{
+    element::{Element, IntoElement, Layout},
+    layout_context::LayoutContext,
+    paint_context::PaintContext,
+};
+use anyhow::Result;
+use gpui::text_layout::LineLayout;
+use parking_lot::Mutex;
+use std::sync::Arc;
+
+impl<V: 'static, S: Into<ArcCow<'static, str>>> IntoElement<V> for S {
+    type Element = Text;
+
+    fn into_element(self) -> Self::Element {
+        Text { text: self.into() }
+    }
+}
+
+pub struct Text {
+    text: ArcCow<'static, str>,
+}
+
+impl<V: 'static> Element<V> for Text {
+    type Layout = Arc<Mutex<Option<TextLayout>>>;
+
+    fn layout(
+        &mut self,
+        view: &mut V,
+        cx: &mut LayoutContext<V>,
+    ) -> Result<Layout<V, Self::Layout>> {
+        // let rem_size = cx.rem_pixels();
+        // let fonts = cx.platform().fonts();
+        // let text_style = cx.text_style();
+        // let line_height = cx.font_cache().line_height(text_style.font_size);
+        // let layout_engine = cx.layout_engine().expect("no layout engine present");
+        // let text = self.text.clone();
+        // let layout = Arc::new(Mutex::new(None));
+
+        // let style: Style = Style::default().refined(&self.metadata.style);
+        // let node_id = layout_engine.add_measured_node(style.to_taffy(rem_size), {
+        //     let layout = layout.clone();
+        //     move |params| {
+        //         let line_layout = fonts.layout_line(
+        //             text.as_ref(),
+        //             text_style.font_size,
+        //             &[(text.len(), text_style.to_run())],
+        //         );
+
+        //         let size = Size {
+        //             width: line_layout.width,
+        //             height: line_height,
+        //         };
+
+        //         layout.lock().replace(TextLayout {
+        //             line_layout: Arc::new(line_layout),
+        //             line_height,
+        //         });
+
+        //         size
+        //     }
+        // })?;
+
+        // Ok((node_id, layout))
+        todo!()
+    }
+
+    fn paint<'a>(
+        &mut self,
+        view: &mut V,
+        layout: &mut Layout<V, Self::Layout>,
+        cx: &mut PaintContext<V>,
+    ) {
+        // ) {
+        //     let element_layout_lock = layout.from_element.lock();
+        //     let element_layout = element_layout_lock
+        //         .as_ref()
+        //         .expect("layout has not been performed");
+        //     let line_layout = element_layout.line_layout.clone();
+        //     let line_height = element_layout.line_height;
+        //     drop(element_layout_lock);
+
+        //     let text_style = cx.text_style();
+        //     let line =
+        //         gpui::text_layout::Line::new(line_layout, &[(self.text.len(), text_style.to_run())]);
+        //     line.paint(
+        //         cx.scene,
+        //         layout.from_engine.bounds.origin(),
+        //         layout.from_engine.bounds,
+        //         line_height,
+        //         cx.legacy_cx,
+        //     );
+        todo!()
+    }
+}
+
+pub struct TextLayout {
+    line_layout: Arc<LineLayout>,
+    line_height: f32,
+}
+
+pub enum ArcCow<'a, T: ?Sized> {
+    Borrowed(&'a T),
+    Owned(Arc<T>),
+}
+
+impl<'a, T: ?Sized> Clone for ArcCow<'a, T> {
+    fn clone(&self) -> Self {
+        match self {
+            Self::Borrowed(borrowed) => Self::Borrowed(borrowed),
+            Self::Owned(owned) => Self::Owned(owned.clone()),
+        }
+    }
+}
+
+impl<'a, T: ?Sized> From<&'a T> for ArcCow<'a, T> {
+    fn from(s: &'a T) -> Self {
+        Self::Borrowed(s)
+    }
+}
+
+impl<T> From<Arc<T>> for ArcCow<'_, T> {
+    fn from(s: Arc<T>) -> Self {
+        Self::Owned(s)
+    }
+}
+
+impl From<String> for ArcCow<'_, str> {
+    fn from(value: String) -> Self {
+        Self::Owned(value.into())
+    }
+}
+
+impl<T: ?Sized> std::ops::Deref for ArcCow<'_, T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        match self {
+            ArcCow::Borrowed(s) => s,
+            ArcCow::Owned(s) => s.as_ref(),
+        }
+    }
+}
+
+impl<T: ?Sized> AsRef<T> for ArcCow<'_, T> {
+    fn as_ref(&self) -> &T {
+        match self {
+            ArcCow::Borrowed(borrowed) => borrowed,
+            ArcCow::Owned(owned) => owned.as_ref(),
+        }
+    }
+}

crates/gpui/playground/src/themes.rs

@@ -0,0 +1,84 @@
+use crate::color::{Hsla, Lerp};
+use std::ops::Range;
+
+pub mod rose_pine;
+
+pub struct ThemeColors {
+    pub base: Range<Hsla>,
+    pub surface: Range<Hsla>,
+    pub overlay: Range<Hsla>,
+    pub muted: Range<Hsla>,
+    pub subtle: Range<Hsla>,
+    pub text: Range<Hsla>,
+    pub highlight_low: Range<Hsla>,
+    pub highlight_med: Range<Hsla>,
+    pub highlight_high: Range<Hsla>,
+    pub success: Range<Hsla>,
+    pub warning: Range<Hsla>,
+    pub error: Range<Hsla>,
+    pub inserted: Range<Hsla>,
+    pub deleted: Range<Hsla>,
+    pub modified: Range<Hsla>,
+}
+
+impl ThemeColors {
+    pub fn base(&self, level: f32) -> Hsla {
+        self.base.lerp(level)
+    }
+
+    pub fn surface(&self, level: f32) -> Hsla {
+        self.surface.lerp(level)
+    }
+
+    pub fn overlay(&self, level: f32) -> Hsla {
+        self.overlay.lerp(level)
+    }
+
+    pub fn muted(&self, level: f32) -> Hsla {
+        self.muted.lerp(level)
+    }
+
+    pub fn subtle(&self, level: f32) -> Hsla {
+        self.subtle.lerp(level)
+    }
+
+    pub fn text(&self, level: f32) -> Hsla {
+        self.text.lerp(level)
+    }
+
+    pub fn highlight_low(&self, level: f32) -> Hsla {
+        self.highlight_low.lerp(level)
+    }
+
+    pub fn highlight_med(&self, level: f32) -> Hsla {
+        self.highlight_med.lerp(level)
+    }
+
+    pub fn highlight_high(&self, level: f32) -> Hsla {
+        self.highlight_high.lerp(level)
+    }
+
+    pub fn success(&self, level: f32) -> Hsla {
+        self.success.lerp(level)
+    }
+
+    pub fn warning(&self, level: f32) -> Hsla {
+        self.warning.lerp(level)
+    }
+
+    pub fn error(&self, level: f32) -> Hsla {
+        self.error.lerp(level)
+    }
+
+    pub fn inserted(&self, level: f32) -> Hsla {
+        self.inserted.lerp(level)
+    }
+
+    pub fn deleted(&self, level: f32) -> Hsla {
+        self.deleted.lerp(level)
+    }
+
+    pub fn modified(&self, level: f32) -> Hsla {
+        self.modified.lerp(level)
+    }
+}

crates/gpui/playground/src/themes/rose_pine.rs

@@ -0,0 +1,133 @@
+use std::ops::Range;
+
+use crate::{
+    color::{hsla, rgb, Hsla},
+    ThemeColors,
+};
+
+pub struct RosePineThemes {
+    pub default: RosePinePalette,
+    pub dawn: RosePinePalette,
+    pub moon: RosePinePalette,
+}
+
+#[derive(Clone, Copy, Debug)]
+pub struct RosePinePalette {
+    pub base: Hsla,
+    pub surface: Hsla,
+    pub overlay: Hsla,
+    pub muted: Hsla,
+    pub subtle: Hsla,
+    pub text: Hsla,
+    pub love: Hsla,
+    pub gold: Hsla,
+    pub rose: Hsla,
+    pub pine: Hsla,
+    pub foam: Hsla,
+    pub iris: Hsla,
+    pub highlight_low: Hsla,
+    pub highlight_med: Hsla,
+    pub highlight_high: Hsla,
+}
+
+impl RosePinePalette {
+    pub fn default() -> RosePinePalette {
+        RosePinePalette {
+            base: rgb(0x191724),
+            surface: rgb(0x1f1d2e),
+            overlay: rgb(0x26233a),
+            muted: rgb(0x6e6a86),
+            subtle: rgb(0x908caa),
+            text: rgb(0xe0def4),
+            love: rgb(0xeb6f92),
+            gold: rgb(0xf6c177),
+            rose: rgb(0xebbcba),
+            pine: rgb(0x31748f),
+            foam: rgb(0x9ccfd8),
+            iris: rgb(0xc4a7e7),
+            highlight_low: rgb(0x21202e),
+            highlight_med: rgb(0x403d52),
+            highlight_high: rgb(0x524f67),
+        }
+    }
+
+    pub fn moon() -> RosePinePalette {
+        RosePinePalette {
+            base: rgb(0x232136),
+            surface: rgb(0x2a273f),
+            overlay: rgb(0x393552),
+            muted: rgb(0x6e6a86),
+            subtle: rgb(0x908caa),
+            text: rgb(0xe0def4),
+            love: rgb(0xeb6f92),
+            gold: rgb(0xf6c177),
+            rose: rgb(0xea9a97),
+            pine: rgb(0x3e8fb0),
+            foam: rgb(0x9ccfd8),
+            iris: rgb(0xc4a7e7),
+            highlight_low: rgb(0x2a283e),
+            highlight_med: rgb(0x44415a),
+            highlight_high: rgb(0x56526e),
+        }
+    }
+
+    pub fn dawn() -> RosePinePalette {
+        RosePinePalette {
+            base: rgb(0xfaf4ed),
+            surface: rgb(0xfffaf3),
+            overlay: rgb(0xf2e9e1),
+            muted: rgb(0x9893a5),
+            subtle: rgb(0x797593),
+            text: rgb(0x575279),
+            love: rgb(0xb4637a),
+            gold: rgb(0xea9d34),
+            rose: rgb(0xd7827e),
+            pine: rgb(0x286983),
+            foam: rgb(0x56949f),
+            iris: rgb(0x907aa9),
+            highlight_low: rgb(0xf4ede8),
+            highlight_med: rgb(0xdfdad9),
+            highlight_high: rgb(0xcecacd),
+        }
+    }
+}
+
+pub fn default() -> ThemeColors {
+    theme_colors(&RosePinePalette::default())
+}
+
+pub fn moon() -> ThemeColors {
+    theme_colors(&RosePinePalette::moon())
+}
+
+pub fn dawn() -> ThemeColors {
+    theme_colors(&RosePinePalette::dawn())
+}
+
+fn theme_colors(p: &RosePinePalette) -> ThemeColors {
+    ThemeColors {
+        base: scale_sl(p.base, (0.8, 0.8), (1.2, 1.2)),
+        surface: scale_sl(p.surface, (0.8, 0.8), (1.2, 1.2)),
+        overlay: scale_sl(p.overlay, (0.8, 0.8), (1.2, 1.2)),
+        muted: scale_sl(p.muted, (0.8, 0.8), (1.2, 1.2)),
+        subtle: scale_sl(p.subtle, (0.8, 0.8), (1.2, 1.2)),
+        text: scale_sl(p.text, (0.8, 0.8), (1.2, 1.2)),
+        highlight_low: scale_sl(p.highlight_low, (0.8, 0.8), (1.2, 1.2)),
+        highlight_med: scale_sl(p.highlight_med, (0.8, 0.8), (1.2, 1.2)),
+        highlight_high: scale_sl(p.highlight_high, (0.8, 0.8), (1.2, 1.2)),
+        success: scale_sl(p.foam, (0.8, 0.8), (1.2, 1.2)),
+        warning: scale_sl(p.gold, (0.8, 0.8), (1.2, 1.2)),
+        error: scale_sl(p.love, (0.8, 0.8), (1.2, 1.2)),
+        inserted: scale_sl(p.foam, (0.8, 0.8), (1.2, 1.2)),
+        deleted: scale_sl(p.love, (0.8, 0.8), (1.2, 1.2)),
+        modified: scale_sl(p.rose, (0.8, 0.8), (1.2, 1.2)),
+    }
+}
+
+/// Produces a range by multiplying the saturation and lightness of the base color by the given
+/// start and end factors.
+fn scale_sl(base: Hsla, (start_s, start_l): (f32, f32), (end_s, end_l): (f32, f32)) -> Range<Hsla> {
+    let start = hsla(base.h, base.s * start_s, base.l * start_l, base.a);
+    let end = hsla(base.h, base.s * end_s, base.l * end_l, base.a);
+    Range { start, end }
+}

crates/gpui/playground/src/view.rs

@@ -0,0 +1,26 @@
+use crate::{
+    adapter::AdapterElement,
+    element::{AnyElement, Element},
+};
+use gpui::ViewContext;
+
+pub fn view<F, E>(mut render: F) -> ViewFn
+where
+    F: 'static + FnMut(&mut ViewContext<ViewFn>) -> E,
+    E: Element<ViewFn>,
+{
+    ViewFn(Box::new(move |cx| (render)(cx).into_any()))
+}
+
+pub struct ViewFn(Box<dyn FnMut(&mut ViewContext<ViewFn>) -> AnyElement<ViewFn>>);
+
+impl gpui::Entity for ViewFn {
+    type Event = ();
+}
+
+impl gpui::View for ViewFn {
+    fn render(&mut self, cx: &mut ViewContext<Self>) -> gpui::AnyElement<Self> {
+        use gpui::Element as _;
+        AdapterElement((self.0)(cx)).into_any()
+    }
+}

crates/gpui/playground_macros/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "playground_macros"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[lib]
+path = "src/playground_macros.rs"
+proc-macro = true
+
+[dependencies]
+syn = "1.0.72"
+quote = "1.0.9"
+proc-macro2 = "1.0.66"

crates/gpui/playground_macros/src/derive_element.rs

@@ -0,0 +1,91 @@
+use proc_macro::TokenStream;
+use proc_macro2::Ident;
+use quote::quote;
+use syn::{parse_macro_input, parse_quote, DeriveInput, GenericParam, Generics};
+
+use crate::derive_into_element::impl_into_element;
+
+pub fn derive_element(input: TokenStream) -> TokenStream {
+    let ast = parse_macro_input!(input as DeriveInput);
+    let type_name = ast.ident;
+    let placeholder_view_generics: Generics = parse_quote! { <V: 'static> };
+
+    let (impl_generics, type_generics, where_clause, view_type_name, lifetimes) =
+        if let Some(first_type_param) = ast.generics.params.iter().find_map(|param| {
+            if let GenericParam::Type(type_param) = param {
+                Some(type_param.ident.clone())
+            } else {
+                None
+            }
+        }) {
+            let mut lifetimes = vec![];
+            for param in ast.generics.params.iter() {
+                if let GenericParam::Lifetime(lifetime_def) = param {
+                    lifetimes.push(lifetime_def.lifetime.clone());
+                }
+            }
+            let generics = ast.generics.split_for_impl();
+            (
+                generics.0,
+                Some(generics.1),
+                generics.2,
+                first_type_param,
+                lifetimes,
+            )
+        } else {
+            let generics = placeholder_view_generics.split_for_impl();
+            let placeholder_view_type_name: Ident = parse_quote! { V };
+            (
+                generics.0,
+                None,
+                generics.2,
+                placeholder_view_type_name,
+                vec![],
+            )
+        };
+
+    let lifetimes = if !lifetimes.is_empty() {
+        quote! { <#(#lifetimes),*> }
+    } else {
+        quote! {}
+    };
+
+    let impl_into_element = impl_into_element(
+        &impl_generics,
+        &view_type_name,
+        &type_name,
+        &type_generics,
+        &where_clause,
+    );
+
+    let gen = quote! {
+        impl #impl_generics playground::element::Element<#view_type_name> for #type_name #type_generics
+        #where_clause
+        {
+            type Layout = Option<playground::element::AnyElement<#view_type_name #lifetimes>>;
+
+            fn layout(
+                &mut self,
+                view: &mut V,
+                cx: &mut playground::element::LayoutContext<V>,
+            ) -> anyhow::Result<playground::element::Layout<V, Self::Layout>> {
+                let mut element = self.render(view, cx).into_any();
+                let layout_id = element.layout(view, cx)?;
+                Ok(playground::element::Layout::new(layout_id, Some(element)))
+            }
+
+            fn paint(
+                &mut self,
+                view: &mut V,
+                layout: &mut playground::element::Layout<V, Self::Layout>,
+                cx: &mut playground::element::PaintContext<V>,
+            ) {
+                layout.paint(view, cx);
+            }
+        }
+
+        #impl_into_element
+    };
+
+    gen.into()
+}

crates/gpui/playground_macros/src/derive_into_element.rs

@@ -0,0 +1,69 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{
+    parse_macro_input, parse_quote, DeriveInput, GenericParam, Generics, Ident, WhereClause,
+};
+
+pub fn derive_into_element(input: TokenStream) -> TokenStream {
+    let ast = parse_macro_input!(input as DeriveInput);
+    let type_name = ast.ident;
+
+    let placeholder_view_generics: Generics = parse_quote! { <V: 'static> };
+    let placeholder_view_type_name: Ident = parse_quote! { V };
+    let view_type_name: Ident;
+    let impl_generics: syn::ImplGenerics<'_>;
+    let type_generics: Option<syn::TypeGenerics<'_>>;
+    let where_clause: Option<&'_ WhereClause>;
+
+    match ast.generics.params.iter().find_map(|param| {
+        if let GenericParam::Type(type_param) = param {
+            Some(type_param.ident.clone())
+        } else {
+            None
+        }
+    }) {
+        Some(type_name) => {
+            view_type_name = type_name;
+            let generics = ast.generics.split_for_impl();
+            impl_generics = generics.0;
+            type_generics = Some(generics.1);
+            where_clause = generics.2;
+        }
+        _ => {
+            view_type_name = placeholder_view_type_name;
+            let generics = placeholder_view_generics.split_for_impl();
+            impl_generics = generics.0;
+            type_generics = None;
+            where_clause = generics.2;
+        }
+    }
+
+    impl_into_element(
+        &impl_generics,
+        &view_type_name,
+        &type_name,
+        &type_generics,
+        &where_clause,
+    )
+    .into()
+}
+
+pub fn impl_into_element(
+    impl_generics: &syn::ImplGenerics<'_>,
+    view_type_name: &Ident,
+    type_name: &Ident,
+    type_generics: &Option<syn::TypeGenerics<'_>>,
+    where_clause: &Option<&WhereClause>,
+) -> proc_macro2::TokenStream {
+    quote! {
+        impl #impl_generics playground::element::IntoElement<#view_type_name> for #type_name #type_generics
+        #where_clause
+        {
+            type Element = Self;
+
+            fn into_element(self) -> Self {
+                self
+            }
+        }
+    }
+}

crates/gpui/playground_macros/src/playground_macros.rs

@@ -0,0 +1,26 @@
+use proc_macro::TokenStream;
+
+mod derive_element;
+mod derive_into_element;
+mod styleable_helpers;
+mod tailwind_lengths;
+
+#[proc_macro]
+pub fn styleable_helpers(args: TokenStream) -> TokenStream {
+    styleable_helpers::styleable_helpers(args)
+}
+
+#[proc_macro_derive(Element, attributes(element_crate))]
+pub fn derive_element(input: TokenStream) -> TokenStream {
+    derive_element::derive_element(input)
+}
+
+#[proc_macro_derive(IntoElement, attributes(element_crate))]
+pub fn derive_into_element(input: TokenStream) -> TokenStream {
+    derive_into_element::derive_into_element(input)
+}
+
+#[proc_macro_attribute]
+pub fn tailwind_lengths(attr: TokenStream, item: TokenStream) -> TokenStream {
+    tailwind_lengths::tailwind_lengths(attr, item)
+}

crates/gpui/playground_macros/src/styleable_helpers.rs

@@ -0,0 +1,147 @@
+use proc_macro::TokenStream;
+use proc_macro2::TokenStream as TokenStream2;
+use quote::{format_ident, quote};
+use syn::{
+    parse::{Parse, ParseStream, Result},
+    parse_macro_input,
+};
+
+struct StyleableMacroInput;
+
+impl Parse for StyleableMacroInput {
+    fn parse(_input: ParseStream) -> Result<Self> {
+        Ok(StyleableMacroInput)
+    }
+}
+
+pub fn styleable_helpers(input: TokenStream) -> TokenStream {
+    let _ = parse_macro_input!(input as StyleableMacroInput);
+    let methods = generate_methods();
+    let output = quote! {
+        #(#methods)*
+    };
+    output.into()
+}
+
+fn generate_methods() -> Vec<TokenStream2> {
+    let mut methods = Vec::new();
+
+    for (prefix, auto_allowed, fields) in tailwind_prefixes() {
+        for (suffix, length_tokens) in tailwind_lengths() {
+            if !auto_allowed && suffix == "auto" {
+                // Conditional to skip "auto"
+                continue;
+            }
+
+            let method_name = format_ident!("{}_{}", prefix, suffix);
+            let field_assignments = fields
+                .iter()
+                .map(|field_tokens| {
+                    quote! {
+                        style.#field_tokens = Some(gpui::geometry::#length_tokens);
+                    }
+                })
+                .collect::<Vec<_>>();
+
+            let method = quote! {
+                fn #method_name(mut self) -> Self where Self: std::marker::Sized {
+                    let mut style = self.declared_style();
+                    #(#field_assignments)*
+                    self
+                }
+            };
+
+            methods.push(method);
+        }
+    }
+
+    methods
+}
+
+fn tailwind_lengths() -> Vec<(&'static str, TokenStream2)> {
+    vec![
+        ("0", quote! { pixels(0.) }),
+        ("1", quote! { rems(0.25) }),
+        ("2", quote! { rems(0.5) }),
+        ("3", quote! { rems(0.75) }),
+        ("4", quote! { rems(1.) }),
+        ("5", quote! { rems(1.25) }),
+        ("6", quote! { rems(1.5) }),
+        ("8", quote! { rems(2.0) }),
+        ("10", quote! { rems(2.5) }),
+        ("12", quote! { rems(3.) }),
+        ("16", quote! { rems(4.) }),
+        ("20", quote! { rems(5.) }),
+        ("24", quote! { rems(6.) }),
+        ("32", quote! { rems(8.) }),
+        ("40", quote! { rems(10.) }),
+        ("48", quote! { rems(12.) }),
+        ("56", quote! { rems(14.) }),
+        ("64", quote! { rems(16.) }),
+        ("72", quote! { rems(18.) }),
+        ("80", quote! { rems(20.) }),
+        ("96", quote! { rems(24.) }),
+        ("auto", quote! { auto() }),
+        ("px", quote! { pixels(1.) }),
+        ("full", quote! { relative(1.) }),
+        ("1_2", quote! { relative(0.5) }),
+        ("1_3", quote! { relative(1./3.) }),
+        ("2_3", quote! { relative(2./3.) }),
+        ("1_4", quote! { relative(0.25) }),
+        ("2_4", quote! { relative(0.5) }),
+        ("3_4", quote! { relative(0.75) }),
+        ("1_5", quote! { relative(0.2) }),
+        ("2_5", quote! { relative(0.4) }),
+        ("3_5", quote! { relative(0.6) }),
+        ("4_5", quote! { relative(0.8) }),
+        ("1_6", quote! { relative(1./6.) }),
+        ("5_6", quote! { relative(5./6.) }),
+        ("1_12", quote! { relative(1./12.) }),
+        // ("screen_50", quote! { DefiniteLength::Vh(50.0) }),
+        // ("screen_75", quote! { DefiniteLength::Vh(75.0) }),
+        // ("screen", quote! { DefiniteLength::Vh(100.0) }),
+    ]
+}
+
+fn tailwind_prefixes() -> Vec<(&'static str, bool, Vec<TokenStream2>)> {
+    vec![
+        ("w", true, vec![quote! { size.width }]),
+        ("h", true, vec![quote! { size.height }]),
+        ("min_w", false, vec![quote! { min_size.width }]),
+        ("min_h", false, vec![quote! { min_size.height }]),
+        ("max_w", false, vec![quote! { max_size.width }]),
+        ("max_h", false, vec![quote! { max_size.height }]),
+        (
+            "m",
+            true,
+            vec![quote! { margin.top }, quote! { margin.bottom }],
+        ),
+        ("mt", true, vec![quote! { margin.top }]),
+        ("mb", true, vec![quote! { margin.bottom }]),
+        (
+            "mx",
+            true,
+            vec![quote! { margin.left }, quote! { margin.right }],
+        ),
+        ("ml", true, vec![quote! { margin.left }]),
+        ("mr", true, vec![quote! { margin.right }]),
+        (
+            "p",
+            false,
+            vec![quote! { padding.top }, quote! { padding.bottom }],
+        ),
+        ("pt", false, vec![quote! { padding.top }]),
+        ("pb", false, vec![quote! { padding.bottom }]),
+        (
+            "px",
+            false,
+            vec![quote! { padding.left }, quote! { padding.right }],
+        ),
+        ("pl", false, vec![quote! { padding.left }]),
+        ("pr", false, vec![quote! { padding.right }]),
+        ("top", true, vec![quote! { inset.top }]),
+        ("bottom", true, vec![quote! { inset.bottom }]),
+        ("left", true, vec![quote! { inset.left }]),
+        ("right", true, vec![quote! { inset.right }]),
+    ]
+}

crates/gpui/playground_macros/src/tailwind_lengths.rs

@@ -0,0 +1,99 @@
+use proc_macro::TokenStream;
+use proc_macro2::TokenStream as TokenStream2;
+use quote::{format_ident, quote};
+use syn::{parse_macro_input, FnArg, ItemFn, PatType};
+
+pub fn tailwind_lengths(_attr: TokenStream, item: TokenStream) -> TokenStream {
+    let input_function = parse_macro_input!(item as ItemFn);
+
+    let visibility = &input_function.vis;
+    let function_signature = input_function.sig.clone();
+    let function_body = input_function.block;
+    let where_clause = &function_signature.generics.where_clause;
+
+    let argument_name = match function_signature.inputs.iter().nth(1) {
+        Some(FnArg::Typed(PatType { pat, .. })) => pat,
+        _ => panic!("Couldn't find the second argument in the function signature"),
+    };
+
+    let mut output_functions = TokenStream2::new();
+
+    for (length, value) in fixed_lengths() {
+        let function_name = format_ident!("{}{}", function_signature.ident, length);
+        output_functions.extend(quote! {
+            #visibility fn #function_name(mut self) -> Self #where_clause {
+                let #argument_name = #value.into();
+                #function_body
+            }
+        });
+    }
+
+    output_functions.into()
+}
+
+fn fixed_lengths() -> Vec<(&'static str, TokenStream2)> {
+    vec![
+        ("0", quote! { DefinedLength::Pixels(0.) }),
+        ("px", quote! { DefinedLength::Pixels(1.) }),
+        ("0_5", quote! { DefinedLength::Rems(0.125) }),
+        ("1", quote! { DefinedLength::Rems(0.25) }),
+        ("1_5", quote! { DefinedLength::Rems(0.375) }),
+        ("2", quote! { DefinedLength::Rems(0.5) }),
+        ("2_5", quote! { DefinedLength::Rems(0.625) }),
+        ("3", quote! { DefinedLength::Rems(0.75) }),
+        ("3_5", quote! { DefinedLength::Rems(0.875) }),
+        ("4", quote! { DefinedLength::Rems(1.) }),
+        ("5", quote! { DefinedLength::Rems(1.25) }),
+        ("6", quote! { DefinedLength::Rems(1.5) }),
+        ("7", quote! { DefinedLength::Rems(1.75) }),
+        ("8", quote! { DefinedLength::Rems(2.) }),
+        ("9", quote! { DefinedLength::Rems(2.25) }),
+        ("10", quote! { DefinedLength::Rems(2.5) }),
+        ("11", quote! { DefinedLength::Rems(2.75) }),
+        ("12", quote! { DefinedLength::Rems(3.) }),
+        ("14", quote! { DefinedLength::Rems(3.5) }),
+        ("16", quote! { DefinedLength::Rems(4.) }),
+        ("20", quote! { DefinedLength::Rems(5.) }),
+        ("24", quote! { DefinedLength::Rems(6.) }),
+        ("28", quote! { DefinedLength::Rems(7.) }),
+        ("32", quote! { DefinedLength::Rems(8.) }),
+        ("36", quote! { DefinedLength::Rems(9.) }),
+        ("40", quote! { DefinedLength::Rems(10.) }),
+        ("44", quote! { DefinedLength::Rems(11.) }),
+        ("48", quote! { DefinedLength::Rems(12.) }),
+        ("52", quote! { DefinedLength::Rems(13.) }),
+        ("56", quote! { DefinedLength::Rems(14.) }),
+        ("60", quote! { DefinedLength::Rems(15.) }),
+        ("64", quote! { DefinedLength::Rems(16.) }),
+        ("72", quote! { DefinedLength::Rems(18.) }),
+        ("80", quote! { DefinedLength::Rems(20.) }),
+        ("96", quote! { DefinedLength::Rems(24.) }),
+        ("half", quote! { DefinedLength::Percent(50.) }),
+        ("1_3rd", quote! { DefinedLength::Percent(33.333333) }),
+        ("2_3rd", quote! { DefinedLength::Percent(66.666667) }),
+        ("1_4th", quote! { DefinedLength::Percent(25.) }),
+        ("2_4th", quote! { DefinedLength::Percent(50.) }),
+        ("3_4th", quote! { DefinedLength::Percent(75.) }),
+        ("1_5th", quote! { DefinedLength::Percent(20.) }),
+        ("2_5th", quote! { DefinedLength::Percent(40.) }),
+        ("3_5th", quote! { DefinedLength::Percent(60.) }),
+        ("4_5th", quote! { DefinedLength::Percent(80.) }),
+        ("1_6th", quote! { DefinedLength::Percent(16.666667) }),
+        ("2_6th", quote! { DefinedLength::Percent(33.333333) }),
+        ("3_6th", quote! { DefinedLength::Percent(50.) }),
+        ("4_6th", quote! { DefinedLength::Percent(66.666667) }),
+        ("5_6th", quote! { DefinedLength::Percent(83.333333) }),
+        ("1_12th", quote! { DefinedLength::Percent(8.333333) }),
+        ("2_12th", quote! { DefinedLength::Percent(16.666667) }),
+        ("3_12th", quote! { DefinedLength::Percent(25.) }),
+        ("4_12th", quote! { DefinedLength::Percent(33.333333) }),
+        ("5_12th", quote! { DefinedLength::Percent(41.666667) }),
+        ("6_12th", quote! { DefinedLength::Percent(50.) }),
+        ("7_12th", quote! { DefinedLength::Percent(58.333333) }),
+        ("8_12th", quote! { DefinedLength::Percent(66.666667) }),
+        ("9_12th", quote! { DefinedLength::Percent(75.) }),
+        ("10_12th", quote! { DefinedLength::Percent(83.333333) }),
+        ("11_12th", quote! { DefinedLength::Percent(91.666667) }),
+        ("full", quote! { DefinedLength::Percent(100.) }),
+    ]
+}

crates/gpui/src/app.rs

@@ -7,42 +7,6 @@ pub mod test_app_context;
 pub(crate) mod window;
 mod window_input_handler;
 
-use std::{
-    any::{type_name, Any, TypeId},
-    cell::RefCell,
-    fmt::{self, Debug},
-    hash::{Hash, Hasher},
-    marker::PhantomData,
-    mem,
-    ops::{Deref, DerefMut, Range},
-    path::{Path, PathBuf},
-    pin::Pin,
-    rc::{self, Rc},
-    sync::{Arc, Weak},
-    time::Duration,
-};
-
-use anyhow::{anyhow, Context, Result};
-
-use derive_more::Deref;
-use parking_lot::Mutex;
-use postage::oneshot;
-use smallvec::SmallVec;
-use smol::prelude::*;
-use util::ResultExt;
-use uuid::Uuid;
-
-pub use action::*;
-use callback_collection::CallbackCollection;
-use collections::{hash_map::Entry, BTreeMap, HashMap, HashSet, VecDeque};
-pub use menu::*;
-use platform::Event;
-#[cfg(any(test, feature = "test-support"))]
-use ref_counts::LeakDetector;
-#[cfg(any(test, feature = "test-support"))]
-pub use test_app_context::{ContextHandle, TestAppContext};
-use window_input_handler::WindowInputHandler;
-
 use crate::{
     elements::{AnyElement, AnyRootElement, RootElement},
     executor::{self, Task},
@@ -57,8 +21,39 @@ use crate::{
     window::{Window, WindowContext},
     AssetCache, AssetSource, ClipboardItem, FontCache, MouseRegionId,
 };
-
+pub use action::*;
-use self::ref_counts::RefCounts;
+use anyhow::{anyhow, Context, Result};
+use callback_collection::CallbackCollection;
+use collections::{hash_map::Entry, BTreeMap, HashMap, HashSet, VecDeque};
+use derive_more::Deref;
+pub use menu::*;
+use parking_lot::Mutex;
+use platform::Event;
+use postage::oneshot;
+#[cfg(any(test, feature = "test-support"))]
+use ref_counts::LeakDetector;
+use ref_counts::RefCounts;
+use smallvec::SmallVec;
+use smol::prelude::*;
+use std::{
+    any::{type_name, Any, TypeId},
+    cell::RefCell,
+    fmt::{self, Debug},
+    hash::{Hash, Hasher},
+    marker::PhantomData,
+    mem,
+    ops::{Deref, DerefMut, Range},
+    path::{Path, PathBuf},
+    pin::Pin,
+    rc::{self, Rc},
+    sync::{Arc, Weak},
+    time::Duration,
+};
+#[cfg(any(test, feature = "test-support"))]
+pub use test_app_context::{ContextHandle, TestAppContext};
+use util::ResultExt;
+use uuid::Uuid;
+use window_input_handler::WindowInputHandler;
 
 pub trait Entity: 'static {
     type Event;
@@ -73,10 +68,12 @@ pub trait Entity: 'static {
 }
 
 pub trait View: Entity + Sized {
-    fn ui_name() -> &'static str;
     fn render(&mut self, cx: &mut ViewContext<'_, '_, Self>) -> AnyElement<Self>;
     fn focus_in(&mut self, _: AnyViewHandle, _: &mut ViewContext<Self>) {}
     fn focus_out(&mut self, _: AnyViewHandle, _: &mut ViewContext<Self>) {}
+    fn ui_name() -> &'static str {
+        type_name::<Self>()
+    }
     fn key_down(&mut self, _: &KeyDownEvent, _: &mut ViewContext<Self>) -> bool {
         false
     }
@@ -640,7 +637,7 @@ impl AppContext {
     pub fn add_action<A, V, F, R>(&mut self, handler: F)
     where
         A: Action,
-        V: View,
+        V: 'static,
         F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>) -> R,
     {
         self.add_action_internal(handler, false)
@@ -649,7 +646,7 @@ impl AppContext {
     pub fn capture_action<A, V, F>(&mut self, handler: F)
     where
         A: Action,
-        V: View,
+        V: 'static,
         F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>),
     {
         self.add_action_internal(handler, true)
@@ -658,7 +655,7 @@ impl AppContext {
     fn add_action_internal<A, V, F, R>(&mut self, mut handler: F, capture: bool)
     where
         A: Action,
-        V: View,
+        V: 'static,
         F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>) -> R,
     {
         let handler = Box::new(
@@ -699,7 +696,7 @@ impl AppContext {
     pub fn add_async_action<A, V, F>(&mut self, mut handler: F)
     where
         A: Action,
-        V: View,
+        V: 'static,
         F: 'static + FnMut(&mut V, &A, &mut ViewContext<V>) -> Option<Task<Result<()>>>,
     {
         self.add_action(move |view, action, cx| {
@@ -898,8 +895,8 @@ impl AppContext {
 
     fn observe_focus<F, V>(&mut self, handle: &ViewHandle<V>, mut callback: F) -> Subscription
     where
+        V: 'static,
         F: 'static + FnMut(ViewHandle<V>, bool, &mut WindowContext) -> bool,
-        V: View,
     {
         let subscription_id = post_inc(&mut self.next_subscription_id);
         let observed = handle.downgrade();
@@ -1382,15 +1379,15 @@ impl AppContext {
         self.windows.keys().copied()
     }
 
-    pub fn read_view<T: View>(&self, handle: &ViewHandle<T>) -> &T {
+    pub fn read_view<V: 'static>(&self, handle: &ViewHandle<V>) -> &V {
         if let Some(view) = self.views.get(&(handle.window, handle.view_id)) {
             view.as_any().downcast_ref().expect("downcast is type safe")
         } else {
-            panic!("circular view reference for type {}", type_name::<T>());
+            panic!("circular view reference for type {}", type_name::<V>());
         }
     }
 
-    fn upgrade_view_handle<T: View>(&self, handle: &WeakViewHandle<T>) -> Option<ViewHandle<T>> {
+    fn upgrade_view_handle<V: 'static>(&self, handle: &WeakViewHandle<V>) -> Option<ViewHandle<V>> {
         if self.ref_counts.lock().is_entity_alive(handle.view_id) {
             Some(ViewHandle::new(
                 handle.window,
@@ -1659,6 +1656,9 @@ impl AppContext {
                             subscription_id,
                             callback,
                         ),
+                        Effect::RepaintWindow { window } => {
+                            self.handle_repaint_window_effect(window)
+                        }
                     }
                     self.pending_notifications.clear();
                 } else {
@@ -1896,6 +1896,15 @@ impl AppContext {
         });
     }
 
+    fn handle_repaint_window_effect(&mut self, window: AnyWindowHandle) {
+        self.update_window(window, |cx| {
+            cx.layout(false).log_err();
+            if let Some(scene) = cx.paint().log_err() {
+                cx.window.platform_window.present_scene(scene);
+            }
+        });
+    }
+
     fn handle_window_activation_effect(&mut self, window: AnyWindowHandle, active: bool) -> bool {
         self.update_window(window, |cx| {
             if cx.window.is_active == active {
@@ -2151,7 +2160,7 @@ struct ViewMetadata {
     keymap_context: KeymapContext,
 }
 
-#[derive(Default, Clone)]
+#[derive(Default, Clone, Debug)]
 pub struct WindowInvalidation {
     pub updated: HashSet<usize>,
     pub removed: Vec<usize>,
@@ -2255,6 +2264,9 @@ pub enum Effect {
         window: AnyWindowHandle,
         is_active: bool,
     },
+    RepaintWindow {
+        window: AnyWindowHandle,
+    },
     WindowActivationObservation {
         window: AnyWindowHandle,
         subscription_id: usize,
@@ -2448,6 +2460,10 @@ impl Debug for Effect {
                 .debug_struct("Effect::ActiveLabeledTasksObservation")
                 .field("subscription_id", subscription_id)
                 .finish(),
+            Effect::RepaintWindow { window } => f
+                .debug_struct("Effect::RepaintWindow")
+                .field("window_id", &window.id())
+                .finish(),
         }
     }
 }
@@ -2543,10 +2559,7 @@ pub trait AnyView {
     }
 }
 
-impl<V> AnyView for V
+impl<V: View> AnyView for V {
-where
-    V: View,
-{
     fn as_any(&self) -> &dyn Any {
         self
     }
@@ -2878,7 +2891,7 @@ pub struct ViewContext<'a, 'b, T: ?Sized> {
     view_type: PhantomData<T>,
 }
 
-impl<'a, 'b, T: View> Deref for ViewContext<'a, 'b, T> {
+impl<'a, 'b, V> Deref for ViewContext<'a, 'b, V> {
     type Target = WindowContext<'a>;
 
     fn deref(&self) -> &Self::Target {
@@ -2886,14 +2899,14 @@ impl<'a, 'b, T: View> Deref for ViewContext<'a, 'b, T> {
     }
 }
 
-impl<T: View> DerefMut for ViewContext<'_, '_, T> {
+impl<'a, 'b, V> DerefMut for ViewContext<'a, 'b, V> {
     fn deref_mut(&mut self) -> &mut Self::Target {
         &mut self.window_context
     }
 }
 
-impl<'a, 'b, V: View> ViewContext<'a, 'b, V> {
+impl<'a, 'b, V: 'static> ViewContext<'a, 'b, V> {
-    pub(crate) fn mutable(window_context: &'b mut WindowContext<'a>, view_id: usize) -> Self {
+    pub fn mutable(window_context: &'b mut WindowContext<'a>, view_id: usize) -> Self {
         Self {
             window_context: Reference::Mutable(window_context),
             view_id,
@@ -2901,7 +2914,7 @@ impl<'a, 'b, V: View> ViewContext<'a, 'b, V> {
         }
     }
 
-    pub(crate) fn immutable(window_context: &'b WindowContext<'a>, view_id: usize) -> Self {
+    pub fn immutable(window_context: &'b WindowContext<'a>, view_id: usize) -> Self {
         Self {
             window_context: Reference::Immutable(window_context),
             view_id,
@@ -2913,6 +2926,12 @@ impl<'a, 'b, V: View> ViewContext<'a, 'b, V> {
         &mut self.window_context
     }
 
+    pub fn notify(&mut self) {
+        let window = self.window_handle;
+        let view_id = self.view_id;
+        self.window_context.notify_view(window, view_id);
+    }
+
     pub fn handle(&self) -> ViewHandle<V> {
         ViewHandle::new(
             self.window_handle,
@@ -3226,21 +3245,6 @@ impl<'a, 'b, V: View> ViewContext<'a, 'b, V> {
         })
     }
 
-    pub fn emit(&mut self, payload: V::Event) {
-        self.window_context
-            .pending_effects
-            .push_back(Effect::Event {
-                entity_id: self.view_id,
-                payload: Box::new(payload),
-            });
-    }
-
-    pub fn notify(&mut self) {
-        let window = self.window_handle;
-        let view_id = self.view_id;
-        self.window_context.notify_view(window, view_id);
-    }
-
     pub fn defer(&mut self, callback: impl 'static + FnOnce(&mut V, &mut ViewContext<V>)) {
         let handle = self.handle();
         self.window_context
@@ -3341,6 +3345,10 @@ impl<'a, 'b, V: View> ViewContext<'a, 'b, V> {
         self.element_state::<Tag, T>(element_id, T::default())
     }
 
+    pub fn rem_pixels(&self) -> f32 {
+        16.
+    }
+
     pub fn default_element_state_dynamic<T: 'static + Default>(
         &mut self,
         tag: TypeTag,
@@ -3350,6 +3358,17 @@ impl<'a, 'b, V: View> ViewContext<'a, 'b, V> {
     }
 }
 
+impl<V: View> ViewContext<'_, '_, V> {
+    pub fn emit(&mut self, event: V::Event) {
+        self.window_context
+            .pending_effects
+            .push_back(Effect::Event {
+                entity_id: self.view_id,
+                payload: Box::new(event),
+            });
+    }
+}
+
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct TypeTag {
     tag: TypeId,
@@ -3428,15 +3447,27 @@ impl<V> BorrowWindowContext for ViewContext<'_, '_, V> {
     }
 }
 
-pub struct LayoutContext<'a, 'b, 'c, V: View> {
+/// Methods shared by both LayoutContext and PaintContext
-    view_context: &'c mut ViewContext<'a, 'b, V>,
+///
+/// It's that PaintContext should be implemented in terms of layout context and
+/// deref to it, in which case we wouldn't need this.
+pub trait RenderContext<'a, 'b, V> {
+    fn text_style(&self) -> TextStyle;
+    fn push_text_style(&mut self, style: TextStyle);
+    fn pop_text_style(&mut self);
+    fn as_view_context(&mut self) -> &mut ViewContext<'a, 'b, V>;
+}
+
+pub struct LayoutContext<'a, 'b, 'c, V> {
+    // Nathan: Making this is public while I work on playground.
+    pub view_context: &'c mut ViewContext<'a, 'b, V>,
     new_parents: &'c mut HashMap<usize, usize>,
     views_to_notify_if_ancestors_change: &'c mut HashMap<usize, SmallVec<[usize; 2]>>,
-    text_style_stack: Vec<Arc<TextStyle>>,
+    text_style_stack: Vec<TextStyle>,
     pub refreshing: bool,
 }
 
-impl<'a, 'b, 'c, V: View> LayoutContext<'a, 'b, 'c, V> {
+impl<'a, 'b, 'c, V> LayoutContext<'a, 'b, 'c, V> {
     pub fn new(
         view_context: &'c mut ViewContext<'a, 'b, V>,
         new_parents: &'c mut HashMap<usize, usize>,
@@ -3500,26 +3531,39 @@ impl<'a, 'b, 'c, V: View> LayoutContext<'a, 'b, 'c, V> {
             .push(self_view_id);
     }
 
-    pub fn text_style(&self) -> Arc<TextStyle> {
+    pub fn with_text_style<F, T>(&mut self, style: TextStyle, f: F) -> T
-        self.text_style_stack
-            .last()
-            .cloned()
-            .unwrap_or(Default::default())
-    }
-
-    pub fn with_text_style<S, F, T>(&mut self, style: S, f: F) -> T
     where
-        S: Into<Arc<TextStyle>>,
         F: FnOnce(&mut Self) -> T,
     {
-        self.text_style_stack.push(style.into());
+        self.push_text_style(style);
         let result = f(self);
-        self.text_style_stack.pop();
+        self.pop_text_style();
         result
     }
 }
 
-impl<'a, 'b, 'c, V: View> Deref for LayoutContext<'a, 'b, 'c, V> {
+impl<'a, 'b, 'c, V> RenderContext<'a, 'b, V> for LayoutContext<'a, 'b, 'c, V> {
+    fn text_style(&self) -> TextStyle {
+        self.text_style_stack
+            .last()
+            .cloned()
+            .unwrap_or(TextStyle::default(&self.font_cache))
+    }
+
+    fn push_text_style(&mut self, style: TextStyle) {
+        self.text_style_stack.push(style);
+    }
+
+    fn pop_text_style(&mut self) {
+        self.text_style_stack.pop();
+    }
+
+    fn as_view_context(&mut self) -> &mut ViewContext<'a, 'b, V> {
+        &mut self.view_context
+    }
+}
+
+impl<'a, 'b, 'c, V> Deref for LayoutContext<'a, 'b, 'c, V> {
     type Target = ViewContext<'a, 'b, V>;
 
     fn deref(&self) -> &Self::Target {
@@ -3527,13 +3571,13 @@ impl<'a, 'b, 'c, V: View> Deref for LayoutContext<'a, 'b, 'c, V> {
     }
 }
 
-impl<V: View> DerefMut for LayoutContext<'_, '_, '_, V> {
+impl<V> DerefMut for LayoutContext<'_, '_, '_, V> {
     fn deref_mut(&mut self) -> &mut Self::Target {
         &mut self.view_context
     }
 }
 
-impl<V: View> BorrowAppContext for LayoutContext<'_, '_, '_, V> {
+impl<V> BorrowAppContext for LayoutContext<'_, '_, '_, V> {
     fn read_with<T, F: FnOnce(&AppContext) -> T>(&self, f: F) -> T {
         BorrowAppContext::read_with(&*self.view_context, f)
     }
@@ -3543,7 +3587,7 @@ impl<V: View> BorrowAppContext for LayoutContext<'_, '_, '_, V> {
     }
 }
 
-impl<V: View> BorrowWindowContext for LayoutContext<'_, '_, '_, V> {
+impl<V> BorrowWindowContext for LayoutContext<'_, '_, '_, V> {
     type Result<T> = T;
 
     fn read_window<T, F: FnOnce(&WindowContext) -> T>(&self, window: AnyWindowHandle, f: F) -> T {
@@ -3573,39 +3617,42 @@ impl<V: View> BorrowWindowContext for LayoutContext<'_, '_, '_, V> {
     }
 }
 
-pub struct PaintContext<'a, 'b, 'c, V: View> {
+pub struct PaintContext<'a, 'b, 'c, V> {
-    view_context: &'c mut ViewContext<'a, 'b, V>,
+    pub view_context: &'c mut ViewContext<'a, 'b, V>,
-    text_style_stack: Vec<Arc<TextStyle>>,
+    text_style_stack: Vec<TextStyle>,
 }
 
-impl<'a, 'b, 'c, V: View> PaintContext<'a, 'b, 'c, V> {
+impl<'a, 'b, 'c, V> PaintContext<'a, 'b, 'c, V> {
     pub fn new(view_context: &'c mut ViewContext<'a, 'b, V>) -> Self {
         Self {
             view_context,
             text_style_stack: Vec::new(),
         }
     }
+}
 
-    pub fn text_style(&self) -> Arc<TextStyle> {
+impl<'a, 'b, 'c, V> RenderContext<'a, 'b, V> for PaintContext<'a, 'b, 'c, V> {
+    fn text_style(&self) -> TextStyle {
         self.text_style_stack
             .last()
             .cloned()
-            .unwrap_or(Default::default())
+            .unwrap_or(TextStyle::default(&self.font_cache))
     }
 
-    pub fn with_text_style<S, F, T>(&mut self, style: S, f: F) -> T
+    fn push_text_style(&mut self, style: TextStyle) {
-    where
+        self.text_style_stack.push(style);
-        S: Into<Arc<TextStyle>>,
+    }
-        F: FnOnce(&mut Self) -> T,
+
-    {
+    fn pop_text_style(&mut self) {
-        self.text_style_stack.push(style.into());
-        let result = f(self);
         self.text_style_stack.pop();
-        result
+    }
+
+    fn as_view_context(&mut self) -> &mut ViewContext<'a, 'b, V> {
+        &mut self.view_context
     }
 }
 
-impl<'a, 'b, 'c, V: View> Deref for PaintContext<'a, 'b, 'c, V> {
+impl<'a, 'b, 'c, V> Deref for PaintContext<'a, 'b, 'c, V> {
     type Target = ViewContext<'a, 'b, V>;
 
     fn deref(&self) -> &Self::Target {
@@ -3613,13 +3660,13 @@ impl<'a, 'b, 'c, V: View> Deref for PaintContext<'a, 'b, 'c, V> {
     }
 }
 
-impl<V: View> DerefMut for PaintContext<'_, '_, '_, V> {
+impl<V> DerefMut for PaintContext<'_, '_, '_, V> {
     fn deref_mut(&mut self) -> &mut Self::Target {
         &mut self.view_context
     }
 }
 
-impl<V: View> BorrowAppContext for PaintContext<'_, '_, '_, V> {
+impl<V> BorrowAppContext for PaintContext<'_, '_, '_, V> {
     fn read_with<T, F: FnOnce(&AppContext) -> T>(&self, f: F) -> T {
         BorrowAppContext::read_with(&*self.view_context, f)
     }
@@ -3629,7 +3676,7 @@ impl<V: View> BorrowAppContext for PaintContext<'_, '_, '_, V> {
     }
 }
 
-impl<V: View> BorrowWindowContext for PaintContext<'_, '_, '_, V> {
+impl<V> BorrowWindowContext for PaintContext<'_, '_, '_, V> {
     type Result<T> = T;
 
     fn read_window<T, F>(&self, window: AnyWindowHandle, f: F) -> Self::Result<T>
@@ -3661,25 +3708,37 @@ impl<V: View> BorrowWindowContext for PaintContext<'_, '_, '_, V> {
     }
 }
 
-pub struct EventContext<'a, 'b, 'c, V: View> {
+pub struct EventContext<'a, 'b, 'c, V> {
     view_context: &'c mut ViewContext<'a, 'b, V>,
     pub(crate) handled: bool,
+    // I would like to replace handled with this.
+    // Being additive for now.
+    pub bubble: bool,
 }
 
-impl<'a, 'b, 'c, V: View> EventContext<'a, 'b, 'c, V> {
+impl<'a, 'b, 'c, V: 'static> EventContext<'a, 'b, 'c, V> {
-    pub(crate) fn new(view_context: &'c mut ViewContext<'a, 'b, V>) -> Self {
+    pub fn new(view_context: &'c mut ViewContext<'a, 'b, V>) -> Self {
         EventContext {
             view_context,
             handled: true,
+            bubble: false,
         }
     }
 
     pub fn propagate_event(&mut self) {
         self.handled = false;
     }
+
+    pub fn bubble_event(&mut self) {
+        self.bubble = true;
+    }
+
+    pub fn event_bubbled(&self) -> bool {
+        self.bubble
+    }
 }
 
-impl<'a, 'b, 'c, V: View> Deref for EventContext<'a, 'b, 'c, V> {
+impl<'a, 'b, 'c, V> Deref for EventContext<'a, 'b, 'c, V> {
     type Target = ViewContext<'a, 'b, V>;
 
     fn deref(&self) -> &Self::Target {
@@ -3687,13 +3746,13 @@ impl<'a, 'b, 'c, V: View> Deref for EventContext<'a, 'b, 'c, V> {
     }
 }
 
-impl<V: View> DerefMut for EventContext<'_, '_, '_, V> {
+impl<V> DerefMut for EventContext<'_, '_, '_, V> {
     fn deref_mut(&mut self) -> &mut Self::Target {
         &mut self.view_context
     }
 }
 
-impl<V: View> BorrowAppContext for EventContext<'_, '_, '_, V> {
+impl<V> BorrowAppContext for EventContext<'_, '_, '_, V> {
     fn read_with<T, F: FnOnce(&AppContext) -> T>(&self, f: F) -> T {
         BorrowAppContext::read_with(&*self.view_context, f)
     }
@@ -3703,7 +3762,7 @@ impl<V: View> BorrowAppContext for EventContext<'_, '_, '_, V> {
     }
 }
 
-impl<V: View> BorrowWindowContext for EventContext<'_, '_, '_, V> {
+impl<V> BorrowWindowContext for EventContext<'_, '_, '_, V> {
     type Result<T> = T;
 
     fn read_window<T, F: FnOnce(&WindowContext) -> T>(&self, window: AnyWindowHandle, f: F) -> T {
@@ -4031,7 +4090,7 @@ impl<V> Clone for WindowHandle<V> {
 
 impl<V> Copy for WindowHandle<V> {}
 
-impl<V: View> WindowHandle<V> {
+impl<V: 'static> WindowHandle<V> {
     fn new(window_id: usize) -> Self {
         WindowHandle {
             any_handle: AnyWindowHandle::new(window_id, TypeId::of::<V>()),
@@ -4069,7 +4128,9 @@ impl<V: View> WindowHandle<V> {
                 .update(cx, update)
         })
     }
+}
 
+impl<V: View> WindowHandle<V> {
     pub fn replace_root<C, F>(&self, cx: &mut C, build_root: F) -> C::Result<ViewHandle<V>>
     where
         C: BorrowWindowContext,
@@ -4149,7 +4210,7 @@ impl AnyWindowHandle {
         self.update(cx, |cx| cx.add_view(build_view))
     }
 
-    pub fn downcast<V: View>(self) -> Option<WindowHandle<V>> {
+    pub fn downcast<V: 'static>(self) -> Option<WindowHandle<V>> {
         if self.root_view_type == TypeId::of::<V>() {
             Some(WindowHandle {
                 any_handle: self,
@@ -4160,7 +4221,7 @@ impl AnyWindowHandle {
         }
     }
 
-    pub fn root_is<V: View>(&self) -> bool {
+    pub fn root_is<V: 'static>(&self) -> bool {
         self.root_view_type == TypeId::of::<V>()
     }
 
@@ -4238,9 +4299,9 @@ impl AnyWindowHandle {
 }
 
 #[repr(transparent)]
-pub struct ViewHandle<T> {
+pub struct ViewHandle<V> {
     any_handle: AnyViewHandle,
-    view_type: PhantomData<T>,
+    view_type: PhantomData<V>,
 }
 
 impl<T> Deref for ViewHandle<T> {
@@ -4251,15 +4312,15 @@ impl<T> Deref for ViewHandle<T> {
     }
 }
 
-impl<T: View> ViewHandle<T> {
+impl<V: 'static> ViewHandle<V> {
     fn new(window: AnyWindowHandle, view_id: usize, ref_counts: &Arc<Mutex<RefCounts>>) -> Self {
         Self {
-            any_handle: AnyViewHandle::new(window, view_id, TypeId::of::<T>(), ref_counts.clone()),
+            any_handle: AnyViewHandle::new(window, view_id, TypeId::of::<V>(), ref_counts.clone()),
             view_type: PhantomData,
         }
     }
 
-    pub fn downgrade(&self) -> WeakViewHandle<T> {
+    pub fn downgrade(&self) -> WeakViewHandle<V> {
         WeakViewHandle::new(self.window, self.view_id)
     }
 
@@ -4275,14 +4336,14 @@ impl<T: View> ViewHandle<T> {
         self.view_id
     }
 
-    pub fn read<'a>(&self, cx: &'a AppContext) -> &'a T {
+    pub fn read<'a>(&self, cx: &'a AppContext) -> &'a V {
         cx.read_view(self)
     }
 
     pub fn read_with<C, F, S>(&self, cx: &C, read: F) -> C::Result<S>
     where
         C: BorrowWindowContext,
-        F: FnOnce(&T, &ViewContext<T>) -> S,
+        F: FnOnce(&V, &ViewContext<V>) -> S,
     {
         cx.read_window(self.window, |cx| {
             let cx = ViewContext::immutable(cx, self.view_id);
@@ -4293,7 +4354,7 @@ impl<T: View> ViewHandle<T> {
     pub fn update<C, F, S>(&self, cx: &mut C, update: F) -> C::Result<S>
     where
         C: BorrowWindowContext,
-        F: FnOnce(&mut T, &mut ViewContext<T>) -> S,
+        F: FnOnce(&mut V, &mut ViewContext<V>) -> S,
     {
         let mut update = Some(update);
 
@@ -4429,8 +4490,8 @@ impl AnyViewHandle {
         TypeId::of::<T>() == self.view_type
     }
 
-    pub fn downcast<T: View>(self) -> Option<ViewHandle<T>> {
+    pub fn downcast<V: 'static>(self) -> Option<ViewHandle<V>> {
-        if self.is::<T>() {
+        if self.is::<V>() {
             Some(ViewHandle {
                 any_handle: self,
                 view_type: PhantomData,
@@ -4440,8 +4501,8 @@ impl AnyViewHandle {
         }
     }
 
-    pub fn downcast_ref<T: View>(&self) -> Option<&ViewHandle<T>> {
+    pub fn downcast_ref<V: 'static>(&self) -> Option<&ViewHandle<V>> {
-        if self.is::<T>() {
+        if self.is::<V>() {
             Some(unsafe { mem::transmute(self) })
         } else {
             None
@@ -4640,7 +4701,7 @@ impl<T> WeakHandle for WeakViewHandle<T> {
     }
 }
 
-impl<V: View> WeakViewHandle<V> {
+impl<V: 'static> WeakViewHandle<V> {
     fn new(window: AnyWindowHandle, view_id: usize) -> Self {
         Self {
             any_handle: AnyWeakViewHandle {
@@ -4680,28 +4741,47 @@ impl<V: View> WeakViewHandle<V> {
         cx.read(|cx| {
             let handle = cx
                 .upgrade_view_handle(self)
-                .ok_or_else(|| anyhow!("view {} was dropped", V::ui_name()))?;
+                .ok_or_else(|| anyhow!("view was dropped"))?;
             cx.read_window(self.window, |cx| handle.read_with(cx, read))
                 .ok_or_else(|| anyhow!("window was removed"))
         })
     }
 
-    pub fn update<T>(
+    pub fn update<T, B>(
         &self,
-        cx: &mut AsyncAppContext,
+        cx: &mut B,
         update: impl FnOnce(&mut V, &mut ViewContext<V>) -> T,
-    ) -> Result<T> {
+    ) -> Result<T>
-        cx.update(|cx| {
+    where
-            let handle = cx
+        B: BorrowWindowContext,
-                .upgrade_view_handle(self)
+        B::Result<Option<T>>: Flatten<T>,
-                .ok_or_else(|| anyhow!("view {} was dropped", V::ui_name()))?;
+    {
-            cx.update_window(self.window, |cx| handle.update(cx, update))
+        cx.update_window(self.window(), |cx| {
-                .ok_or_else(|| anyhow!("window was removed"))
+            cx.upgrade_view_handle(self)
+                .map(|handle| handle.update(cx, update))
         })
+        .flatten()
+        .ok_or_else(|| anyhow!("window was removed"))
     }
 }
 
-impl<T> Deref for WeakViewHandle<T> {
+pub trait Flatten<T> {
+    fn flatten(self) -> Option<T>;
+}
+
+impl<T> Flatten<T> for Option<Option<T>> {
+    fn flatten(self) -> Option<T> {
+        self.flatten()
+    }
+}
+
+impl<T> Flatten<T> for Option<T> {
+    fn flatten(self) -> Option<T> {
+        self
+    }
+}
+
+impl<V> Deref for WeakViewHandle<V> {
     type Target = AnyWeakViewHandle;
 
     fn deref(&self) -> &Self::Target {
@@ -4709,7 +4789,7 @@ impl<T> Deref for WeakViewHandle<T> {
     }
 }
 
-impl<T> Clone for WeakViewHandle<T> {
+impl<V> Clone for WeakViewHandle<V> {
     fn clone(&self) -> Self {
         Self {
             any_handle: self.any_handle.clone(),
@@ -5263,6 +5343,7 @@ mod tests {
                     button: MouseButton::Left,
                     modifiers: Default::default(),
                     click_count: 1,
+                    is_down: true,
                 }),
                 false,
             );

crates/gpui/src/app/window.rs

@@ -1,6 +1,6 @@
 use crate::{
     elements::AnyRootElement,
-    geometry::rect::RectF,
+    geometry::{rect::RectF, Size},
     json::ToJson,
     keymap_matcher::{Binding, KeymapContext, Keystroke, MatchResult},
     platform::{
@@ -8,8 +8,9 @@ use crate::{
         MouseButton, MouseMovedEvent, PromptLevel, WindowBounds,
     },
     scene::{
-        CursorRegion, MouseClick, MouseClickOut, MouseDown, MouseDownOut, MouseDrag, MouseEvent,
+        CursorRegion, EventHandler, MouseClick, MouseClickOut, MouseDown, MouseDownOut, MouseDrag,
-        MouseHover, MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut, Scene,
+        MouseEvent, MouseHover, MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut,
+        Scene,
     },
     text_layout::TextLayoutCache,
     util::post_inc,
@@ -31,7 +32,11 @@ use sqlez::{
 use std::{
     any::TypeId,
     mem,
-    ops::{Deref, DerefMut, Range},
+    ops::{Deref, DerefMut, Range, Sub},
+};
+use taffy::{
+    tree::{Measurable, MeasureFunc},
+    Taffy,
 };
 use util::ResultExt;
 use uuid::Uuid;
@@ -39,6 +44,7 @@ use uuid::Uuid;
 use super::{Reference, ViewMetadata};
 
 pub struct Window {
+    layout_engines: Vec<LayoutEngine>,
     pub(crate) root_view: Option<AnyViewHandle>,
     pub(crate) focused_view_id: Option<usize>,
     pub(crate) parents: HashMap<usize, usize>,
@@ -51,6 +57,7 @@ pub struct Window {
     appearance: Appearance,
     cursor_regions: Vec<CursorRegion>,
     mouse_regions: Vec<(MouseRegion, usize)>,
+    event_handlers: Vec<EventHandler>,
     last_mouse_moved_event: Option<Event>,
     pub(crate) hovered_region_ids: Vec<MouseRegionId>,
     pub(crate) clicked_region_ids: Vec<MouseRegionId>,
@@ -67,12 +74,13 @@ impl Window {
         build_view: F,
     ) -> Self
     where
-        F: FnOnce(&mut ViewContext<V>) -> V,
         V: View,
+        F: FnOnce(&mut ViewContext<V>) -> V,
     {
         let titlebar_height = platform_window.titlebar_height();
         let appearance = platform_window.appearance();
         let mut window = Self {
+            layout_engines: Vec::new(),
             root_view: None,
             focused_view_id: None,
             parents: Default::default(),
@@ -83,6 +91,7 @@ impl Window {
             rendered_views: Default::default(),
             cursor_regions: Default::default(),
             mouse_regions: Default::default(),
+            event_handlers: Default::default(),
             text_layout_cache: TextLayoutCache::new(cx.font_system.clone()),
             last_mouse_moved_event: None,
             hovered_region_ids: Default::default(),
@@ -109,6 +118,10 @@ impl Window {
             .as_ref()
             .expect("root_view called during window construction")
     }
+
+    pub fn take_event_handlers(&mut self) -> Vec<EventHandler> {
+        mem::take(&mut self.event_handlers)
+    }
 }
 
 pub struct WindowContext<'a> {
@@ -207,6 +220,24 @@ impl<'a> WindowContext<'a> {
         }
     }
 
+    pub fn repaint(&mut self) {
+        let window = self.window();
+        self.pending_effects
+            .push_back(Effect::RepaintWindow { window });
+    }
+
+    pub fn layout_engine(&mut self) -> Option<&mut LayoutEngine> {
+        self.window.layout_engines.last_mut()
+    }
+
+    pub fn push_layout_engine(&mut self, engine: LayoutEngine) {
+        self.window.layout_engines.push(engine);
+    }
+
+    pub fn pop_layout_engine(&mut self) -> Option<LayoutEngine> {
+        self.window.layout_engines.pop()
+    }
+
     pub fn remove_window(&mut self) {
         self.removed = true;
     }
@@ -227,6 +258,10 @@ impl<'a> WindowContext<'a> {
         self.window.platform_window.content_size()
     }
 
+    pub fn mouse_position(&self) -> Vector2F {
+        self.window.mouse_position
+    }
+
     pub fn text_layout_cache(&self) -> &TextLayoutCache {
         &self.window.text_layout_cache
     }
@@ -242,14 +277,11 @@ impl<'a> WindowContext<'a> {
         Some(result)
     }
 
-    pub(crate) fn update_view<T, S>(
+    pub(crate) fn update_view<V: 'static, S>(
         &mut self,
-        handle: &ViewHandle<T>,
+        handle: &ViewHandle<V>,
-        update: &mut dyn FnMut(&mut T, &mut ViewContext<T>) -> S,
+        update: &mut dyn FnMut(&mut V, &mut ViewContext<V>) -> S,
-    ) -> S
+    ) -> S {
-    where
-        T: View,
-    {
         self.update_any_view(handle.view_id, |view, cx| {
             let mut cx = ViewContext::mutable(cx, handle.view_id);
             update(
@@ -475,6 +507,8 @@ impl<'a> WindowContext<'a> {
     }
 
     pub(crate) fn dispatch_event(&mut self, event: Event, event_reused: bool) -> bool {
+        self.dispatch_to_new_event_handlers(&event);
+
         let mut mouse_events = SmallVec::<[_; 2]>::new();
         let mut notified_views: HashSet<usize> = Default::default();
         let handle = self.window_handle;
@@ -852,6 +886,18 @@ impl<'a> WindowContext<'a> {
         any_event_handled
     }
 
+    fn dispatch_to_new_event_handlers(&mut self, event: &Event) {
+        if let Some(mouse_event) = event.mouse_event() {
+            let event_handlers = self.window.take_event_handlers();
+            for event_handler in event_handlers.iter().rev() {
+                if event_handler.event_type == mouse_event.type_id() {
+                    (event_handler.handler)(mouse_event, self);
+                }
+            }
+            self.window.event_handlers = event_handlers;
+        }
+    }
+
     pub(crate) fn dispatch_key_down(&mut self, event: &KeyDownEvent) -> bool {
         let handle = self.window_handle;
         if let Some(focused_view_id) = self.window.focused_view_id {
@@ -942,14 +988,16 @@ impl<'a> WindowContext<'a> {
         Ok(element)
     }
 
-    pub(crate) fn layout(&mut self, refreshing: bool) -> Result<HashMap<usize, usize>> {
+    pub fn layout(&mut self, refreshing: bool) -> Result<HashMap<usize, usize>> {
         let window_size = self.window.platform_window.content_size();
         let root_view_id = self.window.root_view().id();
+
         let mut rendered_root = self.window.rendered_views.remove(&root_view_id).unwrap();
+
         let mut new_parents = HashMap::default();
         let mut views_to_notify_if_ancestors_change = HashMap::default();
         rendered_root.layout(
-            SizeConstraint::strict(window_size),
+            SizeConstraint::new(window_size, window_size),
             &mut new_parents,
             &mut views_to_notify_if_ancestors_change,
             refreshing,
@@ -982,7 +1030,7 @@ impl<'a> WindowContext<'a> {
         Ok(old_parents)
     }
 
-    pub(crate) fn paint(&mut self) -> Result<Scene> {
+    pub fn paint(&mut self) -> Result<Scene> {
         let window_size = self.window.platform_window.content_size();
         let scale_factor = self.window.platform_window.scale_factor();
 
@@ -1001,9 +1049,10 @@ impl<'a> WindowContext<'a> {
             .insert(root_view_id, rendered_root);
 
         self.window.text_layout_cache.finish_frame();
-        let scene = scene_builder.build();
+        let mut scene = scene_builder.build();
         self.window.cursor_regions = scene.cursor_regions();
         self.window.mouse_regions = scene.mouse_regions();
+        self.window.event_handlers = scene.take_event_handlers();
 
         if self.window_is_active() {
             if let Some(event) = self.window.last_mouse_moved_event.clone() {
@@ -1014,6 +1063,11 @@ impl<'a> WindowContext<'a> {
         Ok(scene)
     }
 
+    pub fn root_element(&self) -> &Box<dyn AnyRootElement> {
+        let view_id = self.window.root_view().id();
+        self.window.rendered_views.get(&view_id).unwrap()
+    }
+
     pub fn rect_for_text_range(&self, range_utf16: Range<usize>) -> Option<RectF> {
         let focused_view_id = self.window.focused_view_id?;
         self.window
@@ -1216,6 +1270,119 @@ impl<'a> WindowContext<'a> {
     }
 }
 
+#[derive(Default)]
+pub struct LayoutEngine(Taffy);
+pub use taffy::style::Style as LayoutStyle;
+
+impl LayoutEngine {
+    pub fn new() -> Self {
+        Default::default()
+    }
+
+    pub fn add_node<C>(&mut self, style: LayoutStyle, children: C) -> Result<LayoutId>
+    where
+        C: IntoIterator<Item = LayoutId>,
+    {
+        Ok(self
+            .0
+            .new_with_children(style, &children.into_iter().collect::<Vec<_>>())?)
+    }
+
+    pub fn add_measured_node<F>(&mut self, style: LayoutStyle, measure: F) -> Result<LayoutId>
+    where
+        F: Fn(MeasureParams) -> Size<f32> + Sync + Send + 'static,
+    {
+        Ok(self
+            .0
+            .new_leaf_with_measure(style, MeasureFunc::Boxed(Box::new(MeasureFn(measure))))?)
+    }
+
+    pub fn compute_layout(&mut self, root: LayoutId, available_space: Vector2F) -> Result<()> {
+        self.0.compute_layout(
+            root,
+            taffy::geometry::Size {
+                width: available_space.x().into(),
+                height: available_space.y().into(),
+            },
+        )?;
+        Ok(())
+    }
+
+    pub fn computed_layout(&mut self, node: LayoutId) -> Result<EngineLayout> {
+        Ok(self.0.layout(node)?.into())
+    }
+}
+
+pub struct MeasureFn<F>(F);
+
+impl<F: Send + Sync> Measurable for MeasureFn<F>
+where
+    F: Fn(MeasureParams) -> Size<f32>,
+{
+    fn measure(
+        &self,
+        known_dimensions: taffy::prelude::Size<Option<f32>>,
+        available_space: taffy::prelude::Size<taffy::style::AvailableSpace>,
+    ) -> taffy::prelude::Size<f32> {
+        (self.0)(MeasureParams {
+            known_dimensions: known_dimensions.into(),
+            available_space: available_space.into(),
+        })
+        .into()
+    }
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct EngineLayout {
+    pub bounds: RectF,
+    pub order: u32,
+}
+
+pub struct MeasureParams {
+    pub known_dimensions: Size<Option<f32>>,
+    pub available_space: Size<AvailableSpace>,
+}
+
+#[derive(Clone)]
+pub enum AvailableSpace {
+    /// The amount of space available is the specified number of pixels
+    Pixels(f32),
+    /// The amount of space available is indefinite and the node should be laid out under a min-content constraint
+    MinContent,
+    /// The amount of space available is indefinite and the node should be laid out under a max-content constraint
+    MaxContent,
+}
+
+impl Default for AvailableSpace {
+    fn default() -> Self {
+        Self::Pixels(0.)
+    }
+}
+
+impl From<taffy::prelude::AvailableSpace> for AvailableSpace {
+    fn from(value: taffy::prelude::AvailableSpace) -> Self {
+        match value {
+            taffy::prelude::AvailableSpace::Definite(pixels) => Self::Pixels(pixels),
+            taffy::prelude::AvailableSpace::MinContent => Self::MinContent,
+            taffy::prelude::AvailableSpace::MaxContent => Self::MaxContent,
+        }
+    }
+}
+
+impl From<&taffy::tree::Layout> for EngineLayout {
+    fn from(value: &taffy::tree::Layout) -> Self {
+        Self {
+            bounds: RectF::new(
+                vec2f(value.location.x, value.location.y),
+                vec2f(value.size.width, value.size.height),
+            ),
+            order: value.order,
+        }
+    }
+}
+
+pub type LayoutId = taffy::prelude::NodeId;
+
 pub struct RenderParams {
     pub view_id: usize,
     pub titlebar_height: f32,
@@ -1324,6 +1491,12 @@ impl SizeConstraint {
             max: size,
         }
     }
+    pub fn loose(max: Vector2F) -> Self {
+        Self {
+            min: Vector2F::zero(),
+            max,
+        }
+    }
 
     pub fn strict_along(axis: Axis, max: f32) -> Self {
         match axis {
@@ -1360,6 +1533,17 @@ impl SizeConstraint {
     }
 }
 
+impl Sub<Vector2F> for SizeConstraint {
+    type Output = SizeConstraint;
+
+    fn sub(self, rhs: Vector2F) -> SizeConstraint {
+        SizeConstraint {
+            min: self.min - rhs,
+            max: self.max - rhs,
+        }
+    }
+}
+
 impl Default for SizeConstraint {
     fn default() -> Self {
         SizeConstraint {
@@ -1378,6 +1562,7 @@ impl ToJson for SizeConstraint {
     }
 }
 
+#[derive(Clone)]
 pub struct ChildView {
     view_id: usize,
     view_name: &'static str,
@@ -1393,7 +1578,7 @@ impl ChildView {
     }
 }
 
-impl<V: View> Element<V> for ChildView {
+impl<V: 'static> Element<V> for ChildView {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/color.rs

@@ -15,35 +15,75 @@ use serde_json::json;
 
 #[derive(Clone, Copy, Default, PartialEq, Eq, Hash, PartialOrd, Ord, JsonSchema)]
 #[repr(transparent)]
-pub struct Color(#[schemars(with = "String")] ColorU);
+pub struct Color(#[schemars(with = "String")] pub ColorU);
+
+pub fn color(rgba: u32) -> Color {
+    Color::from_u32(rgba)
+}
+
+pub fn rgb(r: f32, g: f32, b: f32) -> Color {
+    Color(ColorF::new(r, g, b, 1.).to_u8())
+}
+
+pub fn rgba(r: f32, g: f32, b: f32, a: f32) -> Color {
+    Color(ColorF::new(r, g, b, a).to_u8())
+}
+
+pub fn transparent_black() -> Color {
+    Color(ColorU::transparent_black())
+}
+
+pub fn black() -> Color {
+    Color(ColorU::black())
+}
+
+pub fn white() -> Color {
+    Color(ColorU::white())
+}
+
+pub fn red() -> Color {
+    color(0xff0000ff)
+}
+
+pub fn green() -> Color {
+    color(0x00ff00ff)
+}
+
+pub fn blue() -> Color {
+    color(0x0000ffff)
+}
+
+pub fn yellow() -> Color {
+    color(0xffff00ff)
+}
 
 impl Color {
     pub fn transparent_black() -> Self {
-        Self(ColorU::transparent_black())
+        transparent_black()
     }
 
     pub fn black() -> Self {
-        Self(ColorU::black())
+        black()
     }
 
     pub fn white() -> Self {
-        Self(ColorU::white())
+        white()
     }
 
     pub fn red() -> Self {
-        Self(ColorU::from_u32(0xff0000ff))
+        Color::from_u32(0xff0000ff)
     }
 
     pub fn green() -> Self {
-        Self(ColorU::from_u32(0x00ff00ff))
+        Color::from_u32(0x00ff00ff)
     }
 
     pub fn blue() -> Self {
-        Self(ColorU::from_u32(0x0000ffff))
+        Color::from_u32(0x0000ffff)
     }
 
     pub fn yellow() -> Self {
-        Self(ColorU::from_u32(0xffff00ff))
+        Color::from_u32(0xffff00ff)
     }
 
     pub fn new(r: u8, g: u8, b: u8, a: u8) -> Self {
@@ -101,6 +141,12 @@ impl<'de> Deserialize<'de> for Color {
     }
 }
 
+impl From<u32> for Color {
+    fn from(value: u32) -> Self {
+        Self(ColorU::from_u32(value))
+    }
+}
+
 impl ToJson for Color {
     fn to_json(&self) -> serde_json::Value {
         json!(format!(

crates/gpui/src/elements.rs

@@ -34,7 +34,7 @@ use crate::{
         rect::RectF,
         vector::{vec2f, Vector2F},
     },
-    json, Action, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, TypeTag, View,
+    json, Action, Entity, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, TypeTag, View,
     ViewContext, WeakViewHandle, WindowContext,
 };
 use anyhow::{anyhow, Result};
@@ -42,14 +42,19 @@ use collections::HashMap;
 use core::panic;
 use json::ToJson;
 use smallvec::SmallVec;
-use std::{any::Any, borrow::Cow, mem, ops::Range};
+use std::{
+    any::{type_name, Any},
+    borrow::Cow,
+    mem,
+    ops::Range,
+};
 
-pub trait Element<V: View>: 'static {
+pub trait Element<V: 'static>: 'static {
     type LayoutState;
     type PaintState;
 
     fn view_name(&self) -> &'static str {
-        V::ui_name()
+        type_name::<V>()
     }
 
     fn layout(
@@ -252,11 +257,7 @@ pub trait Element<V: View>: 'static {
     }
 }
 
-pub trait RenderElement {
+trait AnyElementState<V> {
-    fn render<V: View>(&mut self, view: &mut V, cx: &mut ViewContext<V>) -> AnyElement<V>;
-}
-
-trait AnyElementState<V: View> {
     fn layout(
         &mut self,
         constraint: SizeConstraint,
@@ -270,7 +271,7 @@ trait AnyElementState<V: View> {
         origin: Vector2F,
         visible_bounds: RectF,
         view: &mut V,
-        cx: &mut ViewContext<V>,
+        cx: &mut PaintContext<V>,
     );
 
     fn rect_for_text_range(
@@ -287,7 +288,7 @@ trait AnyElementState<V: View> {
     fn metadata(&self) -> Option<&dyn Any>;
 }
 
-enum ElementState<V: View, E: Element<V>> {
+enum ElementState<V: 'static, E: Element<V>> {
     Empty,
     Init {
         element: E,
@@ -308,7 +309,7 @@ enum ElementState<V: View, E: Element<V>> {
     },
 }
 
-impl<V: View, E: Element<V>> AnyElementState<V> for ElementState<V, E> {
+impl<V, E: Element<V>> AnyElementState<V> for ElementState<V, E> {
     fn layout(
         &mut self,
         constraint: SizeConstraint,
@@ -351,7 +352,7 @@ impl<V: View, E: Element<V>> AnyElementState<V> for ElementState<V, E> {
         origin: Vector2F,
         visible_bounds: RectF,
         view: &mut V,
-        cx: &mut ViewContext<V>,
+        cx: &mut PaintContext<V>,
     ) {
         *self = match mem::take(self) {
             ElementState::PostLayout {
@@ -490,18 +491,18 @@ impl<V: View, E: Element<V>> AnyElementState<V> for ElementState<V, E> {
     }
 }
 
-impl<V: View, E: Element<V>> Default for ElementState<V, E> {
+impl<V, E: Element<V>> Default for ElementState<V, E> {
     fn default() -> Self {
         Self::Empty
     }
 }
 
-pub struct AnyElement<V: View> {
+pub struct AnyElement<V> {
     state: Box<dyn AnyElementState<V>>,
     name: Option<Cow<'static, str>>,
 }
 
-impl<V: View> AnyElement<V> {
+impl<V> AnyElement<V> {
     pub fn name(&self) -> Option<&str> {
         self.name.as_deref()
     }
@@ -527,7 +528,7 @@ impl<V: View> AnyElement<V> {
         origin: Vector2F,
         visible_bounds: RectF,
         view: &mut V,
-        cx: &mut ViewContext<V>,
+        cx: &mut PaintContext<V>,
     ) {
         self.state.paint(scene, origin, visible_bounds, view, cx);
     }
@@ -569,7 +570,7 @@ impl<V: View> AnyElement<V> {
     }
 }
 
-impl<V: View> Element<V> for AnyElement<V> {
+impl<V: 'static> Element<V> for AnyElement<V> {
     type LayoutState = ();
     type PaintState = ();
 
@@ -627,12 +628,18 @@ impl<V: View> Element<V> for AnyElement<V> {
     }
 }
 
-pub struct RootElement<V: View> {
+impl Entity for AnyElement<()> {
+    type Event = ();
+}
+
+// impl View for AnyElement<()> {}
+
+pub struct RootElement<V> {
     element: AnyElement<V>,
     view: WeakViewHandle<V>,
 }
 
-impl<V: View> RootElement<V> {
+impl<V> RootElement<V> {
     pub fn new(element: AnyElement<V>, view: WeakViewHandle<V>) -> Self {
         Self { element, view }
     }
@@ -700,7 +707,9 @@ impl<V: View> AnyRootElement for RootElement<V> {
             .ok_or_else(|| anyhow!("paint called on a root element for a dropped view"))?;
 
         view.update(cx, |view, cx| {
-            self.element.paint(scene, origin, visible_bounds, view, cx);
+            let mut cx = PaintContext::new(cx);
+            self.element
+                .paint(scene, origin, visible_bounds, view, &mut cx);
             Ok(())
         })
     }
@@ -740,7 +749,7 @@ impl<V: View> AnyRootElement for RootElement<V> {
     }
 }
 
-pub trait ParentElement<'a, V: View>: Extend<AnyElement<V>> + Sized {
+pub trait ParentElement<'a, V: 'static>: Extend<AnyElement<V>> + Sized {
     fn add_children<E: Element<V>>(&mut self, children: impl IntoIterator<Item = E>) {
         self.extend(children.into_iter().map(|child| child.into_any()));
     }
@@ -760,7 +769,12 @@ pub trait ParentElement<'a, V: View>: Extend<AnyElement<V>> + Sized {
     }
 }
 
-impl<'a, V: View, T> ParentElement<'a, V> for T where T: Extend<AnyElement<V>> {}
+impl<'a, V, T> ParentElement<'a, V> for T
+where
+    V: 'static,
+    T: Extend<AnyElement<V>>,
+{
+}
 
 pub fn constrain_size_preserving_aspect_ratio(max_size: Vector2F, size: Vector2F) -> Vector2F {
     if max_size.x().is_infinite() && max_size.y().is_infinite() {

crates/gpui/src/elements/align.rs

@@ -1,18 +1,18 @@
 use crate::{
     geometry::{rect::RectF, vector::Vector2F},
-    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
     ViewContext,
 };
 use json::ToJson;
 
 use serde_json::json;
 
-pub struct Align<V: View> {
+pub struct Align<V> {
     child: AnyElement<V>,
     alignment: Vector2F,
 }
 
-impl<V: View> Align<V> {
+impl<V> Align<V> {
     pub fn new(child: AnyElement<V>) -> Self {
         Self {
             child,
@@ -41,7 +41,7 @@ impl<V: View> Align<V> {
     }
 }
 
-impl<V: View> Element<V> for Align<V> {
+impl<V: 'static> Element<V> for Align<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/canvas.rs

@@ -3,7 +3,7 @@ use std::marker::PhantomData;
 use super::Element;
 use crate::{
     json::{self, json},
-    PaintContext, SceneBuilder, View, ViewContext,
+    PaintContext, SceneBuilder, ViewContext,
 };
 use json::ToJson;
 use pathfinder_geometry::{
@@ -15,7 +15,6 @@ pub struct Canvas<V, F>(F, PhantomData<V>);
 
 impl<V, F> Canvas<V, F>
 where
-    V: View,
     F: FnMut(&mut SceneBuilder, RectF, RectF, &mut V, &mut ViewContext<V>),
 {
     pub fn new(f: F) -> Self {
@@ -23,7 +22,7 @@ where
     }
 }
 
-impl<V: View, F> Element<V> for Canvas<V, F>
+impl<V: 'static, F> Element<V> for Canvas<V, F>
 where
     F: 'static + FnMut(&mut SceneBuilder, RectF, RectF, &mut V, &mut ViewContext<V>),
 {

crates/gpui/src/elements/clipped.rs

@@ -4,21 +4,21 @@ use pathfinder_geometry::{rect::RectF, vector::Vector2F};
 use serde_json::json;
 
 use crate::{
-    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
     ViewContext,
 };
 
-pub struct Clipped<V: View> {
+pub struct Clipped<V> {
     child: AnyElement<V>,
 }
 
-impl<V: View> Clipped<V> {
+impl<V> Clipped<V> {
     pub fn new(child: AnyElement<V>) -> Self {
         Self { child }
     }
 }
 
-impl<V: View> Element<V> for Clipped<V> {
+impl<V: 'static> Element<V> for Clipped<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/component.rs

@@ -3,17 +3,16 @@ use std::{any::Any, marker::PhantomData};
 use pathfinder_geometry::{rect::RectF, vector::Vector2F};
 
 use crate::{
-    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, ViewContext,
-    ViewContext,
 };
 
 use super::Empty;
 
 /// The core stateless component trait, simply rendering an element tree
 pub trait Component {
-    fn render<V: View>(self, cx: &mut ViewContext<V>) -> AnyElement<V>;
+    fn render<V: 'static>(self, cx: &mut ViewContext<V>) -> AnyElement<V>;
 
-    fn element<V: View>(self) -> ComponentAdapter<V, Self>
+    fn element<V: 'static>(self) -> ComponentAdapter<V, Self>
     where
         Self: Sized,
     {
@@ -27,7 +26,7 @@ pub trait Component {
         StylableAdapter::new(self)
     }
 
-    fn stateful<V: View>(self) -> StatefulAdapter<Self, V>
+    fn stateful<V: 'static>(self) -> StatefulAdapter<Self, V>
     where
         Self: Sized,
     {
@@ -91,7 +90,7 @@ impl<C: Component> SafeStylable for StylableAdapter<C> {
 /// want to take click handler callbacks Unfortunately, the generic bound on the
 /// Component trait makes it incompatible with the stateless components above.
 // So let's just replicate them for now
-pub trait StatefulComponent<V: View> {
+pub trait StatefulComponent<V: 'static> {
     fn render(self, v: &mut V, cx: &mut ViewContext<V>) -> AnyElement<V>;
 
     fn element(self) -> ComponentAdapter<V, Self>
@@ -118,21 +117,21 @@ pub trait StatefulComponent<V: View> {
 
 /// It is trivial to convert stateless components to stateful components, so lets
 /// do so en masse. Note that the reverse is impossible without a helper.
-impl<V: View, C: Component> StatefulComponent<V> for C {
+impl<V: 'static, C: Component> StatefulComponent<V> for C {
     fn render(self, _: &mut V, cx: &mut ViewContext<V>) -> AnyElement<V> {
         self.render(cx)
     }
 }
 
 /// Same as stylable, but generic over a view type
-pub trait StatefulStylable<V: View>: StatefulComponent<V> {
+pub trait StatefulStylable<V: 'static>: StatefulComponent<V> {
     type Style: Clone;
 
     fn with_style(self, style: Self::Style) -> Self;
 }
 
 /// Same as SafeStylable, but generic over a view type
-pub trait StatefulSafeStylable<V: View> {
+pub trait StatefulSafeStylable<V: 'static> {
     type Style: Clone;
     type Output: StatefulComponent<V>;
 
@@ -140,7 +139,7 @@ pub trait StatefulSafeStylable<V: View> {
 }
 
 /// Converting from stateless to stateful
-impl<V: View, C: SafeStylable> StatefulSafeStylable<V> for C {
+impl<V: 'static, C: SafeStylable> StatefulSafeStylable<V> for C {
     type Style = C::Style;
 
     type Output = C::Output;
@@ -156,7 +155,7 @@ pub struct StatefulAdapter<C, V> {
     phantom: std::marker::PhantomData<V>,
 }
 
-impl<C: Component, V: View> StatefulAdapter<C, V> {
+impl<C: Component, V: 'static> StatefulAdapter<C, V> {
     pub fn new(component: C) -> Self {
         Self {
             component,
@@ -165,7 +164,7 @@ impl<C: Component, V: View> StatefulAdapter<C, V> {
     }
 }
 
-impl<C: Component, V: View> StatefulComponent<V> for StatefulAdapter<C, V> {
+impl<C: Component, V: 'static> StatefulComponent<V> for StatefulAdapter<C, V> {
     fn render(self, _: &mut V, cx: &mut ViewContext<V>) -> AnyElement<V> {
         self.component.render(cx)
     }
@@ -173,12 +172,12 @@ impl<C: Component, V: View> StatefulComponent<V> for StatefulAdapter<C, V> {
 
 // A helper for converting stateful but style-less components into stylable ones
 // by using `()` as the style type
-pub struct StatefulStylableAdapter<C: StatefulComponent<V>, V: View> {
+pub struct StatefulStylableAdapter<C: StatefulComponent<V>, V: 'static> {
     component: C,
     phantom: std::marker::PhantomData<V>,
 }
 
-impl<C: StatefulComponent<V>, V: View> StatefulStylableAdapter<C, V> {
+impl<C: StatefulComponent<V>, V: 'static> StatefulStylableAdapter<C, V> {
     pub fn new(component: C) -> Self {
         Self {
             component,
@@ -187,7 +186,9 @@ impl<C: StatefulComponent<V>, V: View> StatefulStylableAdapter<C, V> {
     }
 }
 
-impl<C: StatefulComponent<V>, V: View> StatefulSafeStylable<V> for StatefulStylableAdapter<C, V> {
+impl<C: StatefulComponent<V>, V: 'static> StatefulSafeStylable<V>
+    for StatefulStylableAdapter<C, V>
+{
     type Style = ();
 
     type Output = C;
@@ -205,7 +206,7 @@ pub struct StatelessElementAdapter {
 }
 
 impl StatelessElementAdapter {
-    pub fn new<V: View>(element: AnyElement<V>) -> Self {
+    pub fn new<V: 'static>(element: AnyElement<V>) -> Self {
         StatelessElementAdapter {
             element: Box::new(element) as Box<dyn Any>,
         }
@@ -213,7 +214,7 @@ impl StatelessElementAdapter {
 }
 
 impl Component for StatelessElementAdapter {
-    fn render<V: View>(self, _: &mut ViewContext<V>) -> AnyElement<V> {
+    fn render<V: 'static>(self, _: &mut ViewContext<V>) -> AnyElement<V> {
         *self
             .element
             .downcast::<AnyElement<V>>()
@@ -222,12 +223,12 @@ impl Component for StatelessElementAdapter {
 }
 
 // For converting elements into stateful components
-pub struct StatefulElementAdapter<V: View> {
+pub struct StatefulElementAdapter<V: 'static> {
     element: AnyElement<V>,
     _phantom: std::marker::PhantomData<V>,
 }
 
-impl<V: View> StatefulElementAdapter<V> {
+impl<V: 'static> StatefulElementAdapter<V> {
     pub fn new(element: AnyElement<V>) -> Self {
         Self {
             element,
@@ -236,7 +237,7 @@ impl<V: View> StatefulElementAdapter<V> {
     }
 }
 
-impl<V: View> StatefulComponent<V> for StatefulElementAdapter<V> {
+impl<V: 'static> StatefulComponent<V> for StatefulElementAdapter<V> {
     fn render(self, _: &mut V, _: &mut ViewContext<V>) -> AnyElement<V> {
         self.element
     }
@@ -244,7 +245,7 @@ impl<V: View> StatefulComponent<V> for StatefulElementAdapter<V> {
 
 /// A convenient shorthand for creating an empty component.
 impl Component for () {
-    fn render<V: View>(self, _: &mut ViewContext<V>) -> AnyElement<V> {
+    fn render<V: 'static>(self, _: &mut ViewContext<V>) -> AnyElement<V> {
         Empty::new().into_any()
     }
 }
@@ -258,13 +259,13 @@ impl Stylable for () {
 }
 
 // For converting components back into Elements
-pub struct ComponentAdapter<V: View, E> {
+pub struct ComponentAdapter<V: 'static, E> {
     component: Option<E>,
     element: Option<AnyElement<V>>,
     phantom: PhantomData<V>,
 }
 
-impl<E, V: View> ComponentAdapter<V, E> {
+impl<E, V: 'static> ComponentAdapter<V, E> {
     pub fn new(e: E) -> Self {
         Self {
             component: Some(e),
@@ -274,7 +275,7 @@ impl<E, V: View> ComponentAdapter<V, E> {
     }
 }
 
-impl<V: View, C: StatefulComponent<V> + 'static> Element<V> for ComponentAdapter<V, C> {
+impl<V: 'static, C: StatefulComponent<V> + 'static> Element<V> for ComponentAdapter<V, C> {
     type LayoutState = ();
 
     type PaintState = ();

crates/gpui/src/elements/constrained_box.rs

@@ -5,21 +5,21 @@ use serde_json::json;
 
 use crate::{
     geometry::{rect::RectF, vector::Vector2F},
-    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
     ViewContext,
 };
 
-pub struct ConstrainedBox<V: View> {
+pub struct ConstrainedBox<V> {
     child: AnyElement<V>,
     constraint: Constraint<V>,
 }
 
-pub enum Constraint<V: View> {
+pub enum Constraint<V> {
     Static(SizeConstraint),
     Dynamic(Box<dyn FnMut(SizeConstraint, &mut V, &mut LayoutContext<V>) -> SizeConstraint>),
 }
 
-impl<V: View> ToJson for Constraint<V> {
+impl<V> ToJson for Constraint<V> {
     fn to_json(&self) -> serde_json::Value {
         match self {
             Constraint::Static(constraint) => constraint.to_json(),
@@ -28,7 +28,7 @@ impl<V: View> ToJson for Constraint<V> {
     }
 }
 
-impl<V: View> ConstrainedBox<V> {
+impl<V: 'static> ConstrainedBox<V> {
     pub fn new(child: impl Element<V>) -> Self {
         Self {
             child: child.into_any(),
@@ -132,7 +132,7 @@ impl<V: View> ConstrainedBox<V> {
     }
 }
 
-impl<V: View> Element<V> for ConstrainedBox<V> {
+impl<V: 'static> Element<V> for ConstrainedBox<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/container.rs

@@ -10,8 +10,7 @@ use crate::{
     json::ToJson,
     platform::CursorStyle,
     scene::{self, Border, CornerRadii, CursorRegion, Quad},
-    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, ViewContext,
-    ViewContext,
 };
 use schemars::JsonSchema;
 use serde::Deserialize;
@@ -55,12 +54,12 @@ impl ContainerStyle {
     }
 }
 
-pub struct Container<V: View> {
+pub struct Container<V> {
     child: AnyElement<V>,
     style: ContainerStyle,
 }
 
-impl<V: View> Container<V> {
+impl<V> Container<V> {
     pub fn new(child: AnyElement<V>) -> Self {
         Self {
             child,
@@ -207,7 +206,7 @@ impl<V: View> Container<V> {
     }
 }
 
-impl<V: View> Element<V> for Container<V> {
+impl<V: 'static> Element<V> for Container<V> {
     type LayoutState = ();
     type PaintState = ();
 
@@ -358,8 +357,8 @@ impl ToJson for ContainerStyle {
 #[derive(Clone, Copy, Debug, Default, JsonSchema)]
 pub struct Margin {
     pub top: f32,
-    pub left: f32,
     pub bottom: f32,
+    pub left: f32,
     pub right: f32,
 }
 

crates/gpui/src/elements/empty.rs

@@ -6,7 +6,7 @@ use crate::{
         vector::{vec2f, Vector2F},
     },
     json::{json, ToJson},
-    LayoutContext, PaintContext, SceneBuilder, View, ViewContext,
+    LayoutContext, PaintContext, SceneBuilder, ViewContext,
 };
 use crate::{Element, SizeConstraint};
 
@@ -26,7 +26,7 @@ impl Empty {
     }
 }
 
-impl<V: View> Element<V> for Empty {
+impl<V: 'static> Element<V> for Empty {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/expanded.rs

@@ -2,18 +2,18 @@ use std::ops::Range;
 
 use crate::{
     geometry::{rect::RectF, vector::Vector2F},
-    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    json, AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
     ViewContext,
 };
 use serde_json::json;
 
-pub struct Expanded<V: View> {
+pub struct Expanded<V> {
     child: AnyElement<V>,
     full_width: bool,
     full_height: bool,
 }
 
-impl<V: View> Expanded<V> {
+impl<V: 'static> Expanded<V> {
     pub fn new(child: impl Element<V>) -> Self {
         Self {
             child: child.into_any(),
@@ -35,7 +35,7 @@ impl<V: View> Expanded<V> {
     }
 }
 
-impl<V: View> Element<V> for Expanded<V> {
+impl<V: 'static> Element<V> for Expanded<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/flex.rs

@@ -3,7 +3,7 @@ use std::{any::Any, cell::Cell, f32::INFINITY, ops::Range, rc::Rc};
 use crate::{
     json::{self, ToJson, Value},
     AnyElement, Axis, Element, ElementStateHandle, LayoutContext, PaintContext, SceneBuilder,
-    SizeConstraint, Vector2FExt, View, ViewContext,
+    SizeConstraint, Vector2FExt, ViewContext,
 };
 use pathfinder_geometry::{
     rect::RectF,
@@ -17,7 +17,7 @@ struct ScrollState {
     scroll_position: Cell<f32>,
 }
 
-pub struct Flex<V: View> {
+pub struct Flex<V> {
     axis: Axis,
     children: Vec<AnyElement<V>>,
     scroll_state: Option<(ElementStateHandle<Rc<ScrollState>>, usize)>,
@@ -25,7 +25,7 @@ pub struct Flex<V: View> {
     spacing: f32,
 }
 
-impl<V: View> Flex<V> {
+impl<V: 'static> Flex<V> {
     pub fn new(axis: Axis) -> Self {
         Self {
             axis,
@@ -127,13 +127,13 @@ impl<V: View> Flex<V> {
     }
 }
 
-impl<V: View> Extend<AnyElement<V>> for Flex<V> {
+impl<V> Extend<AnyElement<V>> for Flex<V> {
     fn extend<T: IntoIterator<Item = AnyElement<V>>>(&mut self, children: T) {
         self.children.extend(children);
     }
 }
 
-impl<V: View> Element<V> for Flex<V> {
+impl<V: 'static> Element<V> for Flex<V> {
     type LayoutState = f32;
     type PaintState = ();
 
@@ -422,12 +422,12 @@ struct FlexParentData {
     float: bool,
 }
 
-pub struct FlexItem<V: View> {
+pub struct FlexItem<V> {
     metadata: FlexParentData,
     child: AnyElement<V>,
 }
 
-impl<V: View> FlexItem<V> {
+impl<V: 'static> FlexItem<V> {
     pub fn new(child: impl Element<V>) -> Self {
         FlexItem {
             metadata: FlexParentData {
@@ -449,7 +449,7 @@ impl<V: View> FlexItem<V> {
     }
 }
 
-impl<V: View> Element<V> for FlexItem<V> {
+impl<V: 'static> Element<V> for FlexItem<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/hook.rs

@@ -3,16 +3,15 @@ use std::ops::Range;
 use crate::{
     geometry::{rect::RectF, vector::Vector2F},
     json::json,
-    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, ViewContext,
-    ViewContext,
 };
 
-pub struct Hook<V: View> {
+pub struct Hook<V> {
     child: AnyElement<V>,
     after_layout: Option<Box<dyn FnMut(Vector2F, &mut ViewContext<V>)>>,
 }
 
-impl<V: View> Hook<V> {
+impl<V: 'static> Hook<V> {
     pub fn new(child: impl Element<V>) -> Self {
         Self {
             child: child.into_any(),
@@ -29,7 +28,7 @@ impl<V: View> Hook<V> {
     }
 }
 
-impl<V: View> Element<V> for Hook<V> {
+impl<V: 'static> Element<V> for Hook<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/image.rs

@@ -6,7 +6,7 @@ use crate::{
     },
     json::{json, ToJson},
     scene, Border, Element, ImageData, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
-    View, ViewContext,
+    ViewContext,
 };
 use schemars::JsonSchema;
 use serde::Deserialize;
@@ -57,7 +57,7 @@ impl Image {
     }
 }
 
-impl<V: View> Element<V> for Image {
+impl<V: 'static> Element<V> for Image {
     type LayoutState = Option<Arc<ImageData>>;
     type PaintState = ();
 

crates/gpui/src/elements/keystroke_label.rs

@@ -31,7 +31,7 @@ impl KeystrokeLabel {
     }
 }
 
-impl<V: View> Element<V> for KeystrokeLabel {
+impl<V: 'static> Element<V> for KeystrokeLabel {
     type LayoutState = AnyElement<V>;
     type PaintState = ();
 

crates/gpui/src/elements/label.rs

@@ -8,7 +8,7 @@ use crate::{
     },
     json::{ToJson, Value},
     text_layout::{Line, RunStyle},
-    Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View, ViewContext,
+    Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, ViewContext,
 };
 use schemars::JsonSchema;
 use serde::Deserialize;
@@ -128,7 +128,7 @@ impl Label {
     }
 }
 
-impl<V: View> Element<V> for Label {
+impl<V: 'static> Element<V> for Label {
     type LayoutState = Line;
     type PaintState = ();
 

crates/gpui/src/elements/list.rs

@@ -5,16 +5,16 @@ use crate::{
     },
     json::json,
     AnyElement, Element, LayoutContext, MouseRegion, PaintContext, SceneBuilder, SizeConstraint,
-    View, ViewContext,
+    ViewContext,
 };
 use std::{cell::RefCell, collections::VecDeque, fmt::Debug, ops::Range, rc::Rc};
 use sum_tree::{Bias, SumTree};
 
-pub struct List<V: View> {
+pub struct List<V> {
     state: ListState<V>,
 }
 
-pub struct ListState<V: View>(Rc<RefCell<StateInner<V>>>);
+pub struct ListState<V>(Rc<RefCell<StateInner<V>>>);
 
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum Orientation {
@@ -22,7 +22,7 @@ pub enum Orientation {
     Bottom,
 }
 
-struct StateInner<V: View> {
+struct StateInner<V> {
     last_layout_width: Option<f32>,
     render_item: Box<dyn FnMut(&mut V, usize, &mut ViewContext<V>) -> AnyElement<V>>,
     rendered_range: Range<usize>,
@@ -40,13 +40,13 @@ pub struct ListOffset {
     pub offset_in_item: f32,
 }
 
-enum ListItem<V: View> {
+enum ListItem<V> {
     Unrendered,
     Rendered(Rc<RefCell<AnyElement<V>>>),
     Removed(f32),
 }
 
-impl<V: View> Clone for ListItem<V> {
+impl<V> Clone for ListItem<V> {
     fn clone(&self) -> Self {
         match self {
             Self::Unrendered => Self::Unrendered,
@@ -56,7 +56,7 @@ impl<V: View> Clone for ListItem<V> {
     }
 }
 
-impl<V: View> Debug for ListItem<V> {
+impl<V> Debug for ListItem<V> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             Self::Unrendered => write!(f, "Unrendered"),
@@ -86,13 +86,13 @@ struct UnrenderedCount(usize);
 #[derive(Clone, Debug, Default)]
 struct Height(f32);
 
-impl<V: View> List<V> {
+impl<V> List<V> {
     pub fn new(state: ListState<V>) -> Self {
         Self { state }
     }
 }
 
-impl<V: View> Element<V> for List<V> {
+impl<V: 'static> Element<V> for List<V> {
     type LayoutState = ListOffset;
     type PaintState = ();
 
@@ -347,7 +347,7 @@ impl<V: View> Element<V> for List<V> {
     }
 }
 
-impl<V: View> ListState<V> {
+impl<V: 'static> ListState<V> {
     pub fn new<D, F>(
         element_count: usize,
         orientation: Orientation,
@@ -440,13 +440,13 @@ impl<V: View> ListState<V> {
     }
 }
 
-impl<V: View> Clone for ListState<V> {
+impl<V> Clone for ListState<V> {
     fn clone(&self) -> Self {
         Self(self.0.clone())
     }
 }
 
-impl<V: View> StateInner<V> {
+impl<V: 'static> StateInner<V> {
     fn render_item(
         &mut self,
         ix: usize,
@@ -560,7 +560,7 @@ impl<V: View> StateInner<V> {
     }
 }
 
-impl<V: View> ListItem<V> {
+impl<V> ListItem<V> {
     fn remove(&self) -> Self {
         match self {
             ListItem::Unrendered => ListItem::Unrendered,
@@ -570,7 +570,7 @@ impl<V: View> ListItem<V> {
     }
 }
 
-impl<V: View> sum_tree::Item for ListItem<V> {
+impl<V> sum_tree::Item for ListItem<V> {
     type Summary = ListItemSummary;
 
     fn summary(&self) -> Self::Summary {
@@ -944,7 +944,7 @@ mod tests {
         type Event = ();
     }
 
-    impl View for TestView {
+    impl crate::View for TestView {
         fn ui_name() -> &'static str {
             "TestView"
         }
@@ -968,7 +968,7 @@ mod tests {
         }
     }
 
-    impl<V: View> Element<V> for TestElement {
+    impl<V: 'static> Element<V> for TestElement {
         type LayoutState = ();
         type PaintState = ();
 

crates/gpui/src/elements/mouse_event_handler.rs

@@ -11,12 +11,12 @@ use crate::{
         MouseHover, MouseMove, MouseMoveOut, MouseScrollWheel, MouseUp, MouseUpOut,
     },
     AnyElement, Element, EventContext, LayoutContext, MouseRegion, MouseState, PaintContext,
-    SceneBuilder, SizeConstraint, TypeTag, View, ViewContext,
+    SceneBuilder, SizeConstraint, TypeTag, ViewContext,
 };
 use serde_json::json;
 use std::ops::Range;
 
-pub struct MouseEventHandler<V: View> {
+pub struct MouseEventHandler<V: 'static> {
     child: AnyElement<V>,
     region_id: usize,
     cursor_style: Option<CursorStyle>,
@@ -31,7 +31,7 @@ pub struct MouseEventHandler<V: View> {
 
 /// Element which provides a render_child callback with a MouseState and paints a mouse
 /// region under (or above) it for easy mouse event handling.
-impl<V: View> MouseEventHandler<V> {
+impl<V: 'static> MouseEventHandler<V> {
     pub fn for_child<Tag: 'static>(child: impl Element<V>, region_id: usize) -> Self {
         Self {
             child: child.into_any(),
@@ -267,7 +267,7 @@ impl<V: View> MouseEventHandler<V> {
     }
 }
 
-impl<V: View> Element<V> for MouseEventHandler<V> {
+impl<V: 'static> Element<V> for MouseEventHandler<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/overlay.rs

@@ -4,11 +4,11 @@ use crate::{
     geometry::{rect::RectF, vector::Vector2F},
     json::ToJson,
     AnyElement, Axis, Element, LayoutContext, MouseRegion, PaintContext, SceneBuilder,
-    SizeConstraint, View, ViewContext,
+    SizeConstraint, ViewContext,
 };
 use serde_json::json;
 
-pub struct Overlay<V: View> {
+pub struct Overlay<V> {
     child: AnyElement<V>,
     anchor_position: Option<Vector2F>,
     anchor_corner: AnchorCorner,
@@ -73,7 +73,7 @@ impl AnchorCorner {
     }
 }
 
-impl<V: View> Overlay<V> {
+impl<V: 'static> Overlay<V> {
     pub fn new(child: impl Element<V>) -> Self {
         Self {
             child: child.into_any(),
@@ -117,7 +117,7 @@ impl<V: View> Overlay<V> {
     }
 }
 
-impl<V: View> Element<V> for Overlay<V> {
+impl<V: 'static> Element<V> for Overlay<V> {
     type LayoutState = Vector2F;
     type PaintState = ();
 

crates/gpui/src/elements/resizable.rs

@@ -59,7 +59,7 @@ where
         .and_then(|map| map.0.get(&tag))
 }
 
-pub struct Resizable<V: View> {
+pub struct Resizable<V: 'static> {
     child: AnyElement<V>,
     tag: TypeTag,
     handle_side: HandleSide,
@@ -69,7 +69,7 @@ pub struct Resizable<V: View> {
 
 const DEFAULT_HANDLE_SIZE: f32 = 4.0;
 
-impl<V: View> Resizable<V> {
+impl<V: 'static> Resizable<V> {
     pub fn new<Tag: 'static>(
         child: AnyElement<V>,
         handle_side: HandleSide,
@@ -97,7 +97,7 @@ impl<V: View> Resizable<V> {
     }
 }
 
-impl<V: View> Element<V> for Resizable<V> {
+impl<V: 'static> Element<V> for Resizable<V> {
     type LayoutState = SizeConstraint;
     type PaintState = ();
 
@@ -219,12 +219,12 @@ impl<V: View> Element<V> for Resizable<V> {
 #[derive(Debug, Default)]
 struct ProviderMap(HashMap<TypeTag, (RectF, RectF)>);
 
-pub struct BoundsProvider<V: View, P> {
+pub struct BoundsProvider<V: 'static, P> {
     child: AnyElement<V>,
     phantom: std::marker::PhantomData<P>,
 }
 
-impl<V: View, P: 'static> BoundsProvider<V, P> {
+impl<V: 'static, P: 'static> BoundsProvider<V, P> {
     pub fn new(child: AnyElement<V>) -> Self {
         Self {
             child,

crates/gpui/src/elements/stack.rs

@@ -3,17 +3,16 @@ use std::ops::Range;
 use crate::{
     geometry::{rect::RectF, vector::Vector2F},
     json::{self, json, ToJson},
-    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, View,
+    AnyElement, Element, LayoutContext, PaintContext, SceneBuilder, SizeConstraint, ViewContext,
-    ViewContext,
 };
 
 /// Element which renders it's children in a stack on top of each other.
 /// The first child determines the size of the others.
-pub struct Stack<V: View> {
+pub struct Stack<V> {
     children: Vec<AnyElement<V>>,
 }
 
-impl<V: View> Default for Stack<V> {
+impl<V> Default for Stack<V> {
     fn default() -> Self {
         Self {
             children: Vec::new(),
@@ -21,13 +20,13 @@ impl<V: View> Default for Stack<V> {
     }
 }
 
-impl<V: View> Stack<V> {
+impl<V> Stack<V> {
     pub fn new() -> Self {
         Self::default()
     }
 }
 
-impl<V: View> Element<V> for Stack<V> {
+impl<V: 'static> Element<V> for Stack<V> {
     type LayoutState = ();
     type PaintState = ();
 
@@ -99,7 +98,7 @@ impl<V: View> Element<V> for Stack<V> {
     }
 }
 
-impl<V: View> Extend<AnyElement<V>> for Stack<V> {
+impl<V> Extend<AnyElement<V>> for Stack<V> {
     fn extend<T: IntoIterator<Item = AnyElement<V>>>(&mut self, children: T) {
         self.children.extend(children)
     }

crates/gpui/src/elements/svg.rs

@@ -7,7 +7,7 @@ use crate::{
         rect::RectF,
         vector::{vec2f, Vector2F},
     },
-    scene, Element, LayoutContext, SceneBuilder, SizeConstraint, View, ViewContext,
+    scene, Element, LayoutContext, SceneBuilder, SizeConstraint, ViewContext,
 };
 use schemars::JsonSchema;
 use serde_derive::Deserialize;
@@ -27,7 +27,7 @@ impl Svg {
         }
     }
 
-    pub fn for_style<V: View>(style: SvgStyle) -> impl Element<V> {
+    pub fn for_style<V: 'static>(style: SvgStyle) -> impl Element<V> {
         Self::new(style.asset)
             .with_color(style.color)
             .constrained()
@@ -41,7 +41,7 @@ impl Svg {
     }
 }
 
-impl<V: View> Element<V> for Svg {
+impl<V: 'static> Element<V> for Svg {
     type LayoutState = Option<usvg::Tree>;
     type PaintState = ();
 

crates/gpui/src/elements/text.rs

@@ -8,7 +8,7 @@ use crate::{
     json::{ToJson, Value},
     text_layout::{Line, RunStyle, ShapedBoundary},
     AppContext, Element, FontCache, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
-    TextLayoutCache, View, ViewContext,
+    TextLayoutCache, ViewContext,
 };
 use log::warn;
 use serde_json::json;
@@ -70,7 +70,7 @@ impl Text {
     }
 }
 
-impl<V: View> Element<V> for Text {
+impl<V: 'static> Element<V> for Text {
     type LayoutState = LayoutState;
     type PaintState = ();
 
@@ -338,7 +338,7 @@ impl<V: View> Element<V> for Text {
 }
 
 /// Perform text layout on a series of highlighted chunks of text.
-fn layout_highlighted_chunks<'a>(
+pub fn layout_highlighted_chunks<'a>(
     chunks: impl Iterator<Item = (&'a str, Option<HighlightStyle>)>,
     text_style: &TextStyle,
     text_layout_cache: &TextLayoutCache,

crates/gpui/src/elements/tooltip.rs

@@ -7,7 +7,7 @@ use crate::{
     geometry::{rect::RectF, vector::Vector2F},
     json::json,
     Action, Axis, ElementStateHandle, LayoutContext, PaintContext, SceneBuilder, SizeConstraint,
-    Task, TypeTag, View, ViewContext,
+    Task, TypeTag, ViewContext,
 };
 use schemars::JsonSchema;
 use serde::Deserialize;
@@ -22,7 +22,7 @@ use util::ResultExt;
 
 const DEBOUNCE_TIMEOUT: Duration = Duration::from_millis(500);
 
-pub struct Tooltip<V: View> {
+pub struct Tooltip<V> {
     child: AnyElement<V>,
     tooltip: Option<AnyElement<V>>,
     _state: ElementStateHandle<Rc<TooltipState>>,
@@ -52,7 +52,7 @@ pub struct KeystrokeStyle {
     text: TextStyle,
 }
 
-impl<V: View> Tooltip<V> {
+impl<V: 'static> Tooltip<V> {
     pub fn new<Tag: 'static>(
         id: usize,
         text: impl Into<Cow<'static, str>>,
@@ -181,7 +181,7 @@ impl<V: View> Tooltip<V> {
     }
 }
 
-impl<V: View> Element<V> for Tooltip<V> {
+impl<V: 'static> Element<V> for Tooltip<V> {
     type LayoutState = ();
     type PaintState = ();
 

crates/gpui/src/elements/uniform_list.rs

@@ -6,7 +6,7 @@ use crate::{
     },
     json::{self, json},
     platform::ScrollWheelEvent,
-    AnyElement, LayoutContext, MouseRegion, PaintContext, SceneBuilder, View, ViewContext,
+    AnyElement, LayoutContext, MouseRegion, PaintContext, SceneBuilder, ViewContext,
 };
 use json::ToJson;
 use std::{cell::RefCell, cmp, ops::Range, rc::Rc};
@@ -36,13 +36,13 @@ struct StateInner {
     scroll_to: Option<ScrollTarget>,
 }
 
-pub struct UniformListLayoutState<V: View> {
+pub struct UniformListLayoutState<V> {
     scroll_max: f32,
     item_height: f32,
     items: Vec<AnyElement<V>>,
 }
 
-pub struct UniformList<V: View> {
+pub struct UniformList<V> {
     state: UniformListState,
     item_count: usize,
     #[allow(clippy::type_complexity)]
@@ -53,7 +53,7 @@ pub struct UniformList<V: View> {
     view_id: usize,
 }
 
-impl<V: View> UniformList<V> {
+impl<V: 'static> UniformList<V> {
     pub fn new<F>(
         state: UniformListState,
         item_count: usize,
@@ -61,7 +61,6 @@ impl<V: View> UniformList<V> {
         append_items: F,
     ) -> Self
     where
-        V: View,
         F: 'static + Fn(&mut V, Range<usize>, &mut Vec<AnyElement<V>>, &mut ViewContext<V>),
     {
         Self {
@@ -151,7 +150,7 @@ impl<V: View> UniformList<V> {
     }
 }
 
-impl<V: View> Element<V> for UniformList<V> {
+impl<V: 'static> Element<V> for UniformList<V> {
     type LayoutState = UniformListLayoutState<V>;
     type PaintState = ();
 

crates/gpui/src/fonts.rs

@@ -11,6 +11,7 @@ pub use font_kit::{
     properties::{Properties, Stretch, Style, Weight},
 };
 use ordered_float::OrderedFloat;
+use refineable::Refineable;
 use schemars::JsonSchema;
 use serde::{de, Deserialize, Serialize};
 use serde_json::Value;
@@ -59,7 +60,7 @@ pub struct Features {
     pub zero: Option<bool>,
 }
 
-#[derive(Clone, Debug, JsonSchema)]
+#[derive(Clone, Debug, JsonSchema, Refineable)]
 pub struct TextStyle {
     pub color: Color,
     pub font_family_name: Arc<str>,
@@ -69,6 +70,7 @@ pub struct TextStyle {
     #[schemars(with = "PropertiesDef")]
     pub font_properties: Properties,
     pub underline: Underline,
+    pub soft_wrap: bool,
 }
 
 impl TextStyle {
@@ -90,20 +92,11 @@ impl TextStyle {
             font_size: refinement.font_size.unwrap_or(self.font_size),
             font_properties: refinement.font_properties.unwrap_or(self.font_properties),
             underline: refinement.underline.unwrap_or(self.underline),
+            soft_wrap: refinement.soft_wrap.unwrap_or(self.soft_wrap),
         }
     }
 }
 
-pub struct TextStyleRefinement {
-    pub color: Option<Color>,
-    pub font_family_name: Option<Arc<str>>,
-    pub font_family_id: Option<FamilyId>,
-    pub font_id: Option<FontId>,
-    pub font_size: Option<f32>,
-    pub font_properties: Option<Properties>,
-    pub underline: Option<Underline>,
-}
-
 #[derive(JsonSchema)]
 #[serde(remote = "Properties")]
 pub struct PropertiesDef {
@@ -222,9 +215,31 @@ impl TextStyle {
             font_size,
             font_properties,
             underline,
+            soft_wrap: false,
         })
     }
 
+    pub fn default(font_cache: &FontCache) -> Self {
+        let font_family_id = font_cache.known_existing_family();
+        let font_id = font_cache
+            .select_font(font_family_id, &Default::default())
+            .expect("did not have any font in system-provided family");
+        let font_family_name = font_cache
+            .family_name(font_family_id)
+            .expect("we loaded this family from the font cache, so this should work");
+
+        Self {
+            color: Color::default(),
+            font_family_name,
+            font_family_id,
+            font_id,
+            font_size: 14.,
+            font_properties: Default::default(),
+            underline: Default::default(),
+            soft_wrap: true,
+        }
+    }
+
     pub fn with_font_size(mut self, font_size: f32) -> Self {
         self.font_size = font_size;
         self
@@ -352,24 +367,7 @@ impl Default for TextStyle {
             let font_cache = font_cache
                 .as_ref()
                 .expect("TextStyle::default can only be called within a call to with_font_cache");
-
+            Self::default(font_cache)
-            let font_family_id = font_cache.known_existing_family();
-            let font_id = font_cache
-                .select_font(font_family_id, &Default::default())
-                .expect("did not have any font in system-provided family");
-            let font_family_name = font_cache
-                .family_name(font_family_id)
-                .expect("we loaded this family from the font cache, so this should work");
-
-            Self {
-                color: Default::default(),
-                font_family_name,
-                font_family_id,
-                font_id,
-                font_size: 14.,
-                font_properties: Default::default(),
-                underline: Default::default(),
-            }
         })
     }
 }

crates/gpui/src/geometry.rs

@@ -2,6 +2,7 @@ use super::scene::{Path, PathVertex};
 use crate::{color::Color, json::ToJson};
 pub use pathfinder_geometry::*;
 use rect::RectF;
+use refineable::Refineable;
 use serde::{Deserialize, Deserializer};
 use serde_json::json;
 use vector::{vec2f, Vector2F};
@@ -131,3 +132,258 @@ impl ToJson for RectF {
         json!({"origin": self.origin().to_json(), "size": self.size().to_json()})
     }
 }
+
+#[derive(Refineable)]
+pub struct Point<T: Clone + Default> {
+    pub x: T,
+    pub y: T,
+}
+
+impl<T: Clone + Default> Clone for Point<T> {
+    fn clone(&self) -> Self {
+        Self {
+            x: self.x.clone(),
+            y: self.y.clone(),
+        }
+    }
+}
+
+impl<T: Clone + Default> Into<taffy::geometry::Point<T>> for Point<T> {
+    fn into(self) -> taffy::geometry::Point<T> {
+        taffy::geometry::Point {
+            x: self.x,
+            y: self.y,
+        }
+    }
+}
+
+#[derive(Clone, Refineable)]
+pub struct Size<T: Clone + Default> {
+    pub width: T,
+    pub height: T,
+}
+
+impl<S, T: Clone + Default> From<taffy::geometry::Size<S>> for Size<T>
+where
+    S: Into<T>,
+{
+    fn from(value: taffy::geometry::Size<S>) -> Self {
+        Self {
+            width: value.width.into(),
+            height: value.height.into(),
+        }
+    }
+}
+
+impl<S, T: Clone + Default> Into<taffy::geometry::Size<S>> for Size<T>
+where
+    T: Into<S>,
+{
+    fn into(self) -> taffy::geometry::Size<S> {
+        taffy::geometry::Size {
+            width: self.width.into(),
+            height: self.height.into(),
+        }
+    }
+}
+
+impl Size<DefiniteLength> {
+    pub fn zero() -> Self {
+        Self {
+            width: pixels(0.),
+            height: pixels(0.),
+        }
+    }
+
+    pub fn to_taffy(&self, rem_size: f32) -> taffy::geometry::Size<taffy::style::LengthPercentage> {
+        taffy::geometry::Size {
+            width: self.width.to_taffy(rem_size),
+            height: self.height.to_taffy(rem_size),
+        }
+    }
+}
+
+impl Size<Length> {
+    pub fn auto() -> Self {
+        Self {
+            width: Length::Auto,
+            height: Length::Auto,
+        }
+    }
+
+    pub fn to_taffy<T: From<taffy::prelude::LengthPercentageAuto>>(
+        &self,
+        rem_size: f32,
+    ) -> taffy::geometry::Size<T> {
+        taffy::geometry::Size {
+            width: self.width.to_taffy(rem_size).into(),
+            height: self.height.to_taffy(rem_size).into(),
+        }
+    }
+}
+
+#[derive(Clone, Default, Refineable)]
+pub struct Edges<T: Clone + Default> {
+    pub top: T,
+    pub right: T,
+    pub bottom: T,
+    pub left: T,
+}
+
+impl Edges<DefiniteLength> {
+    pub fn zero() -> Self {
+        Self {
+            top: pixels(0.),
+            right: pixels(0.),
+            bottom: pixels(0.),
+            left: pixels(0.),
+        }
+    }
+
+    pub fn to_taffy(&self, rem_size: f32) -> taffy::geometry::Rect<taffy::style::LengthPercentage> {
+        taffy::geometry::Rect {
+            top: self.top.to_taffy(rem_size),
+            right: self.right.to_taffy(rem_size),
+            bottom: self.bottom.to_taffy(rem_size),
+            left: self.left.to_taffy(rem_size),
+        }
+    }
+}
+
+impl Edges<Length> {
+    pub fn auto() -> Self {
+        Self {
+            top: Length::Auto,
+            right: Length::Auto,
+            bottom: Length::Auto,
+            left: Length::Auto,
+        }
+    }
+
+    pub fn zero() -> Self {
+        Self {
+            top: pixels(0.),
+            right: pixels(0.),
+            bottom: pixels(0.),
+            left: pixels(0.),
+        }
+    }
+
+    pub fn to_taffy(
+        &self,
+        rem_size: f32,
+    ) -> taffy::geometry::Rect<taffy::style::LengthPercentageAuto> {
+        taffy::geometry::Rect {
+            top: self.top.to_taffy(rem_size),
+            right: self.right.to_taffy(rem_size),
+            bottom: self.bottom.to_taffy(rem_size),
+            left: self.left.to_taffy(rem_size),
+        }
+    }
+}
+
+#[derive(Clone, Copy)]
+pub enum AbsoluteLength {
+    Pixels(f32),
+    Rems(f32),
+}
+
+impl AbsoluteLength {
+    pub fn to_pixels(&self, rem_size: f32) -> f32 {
+        match self {
+            AbsoluteLength::Pixels(pixels) => *pixels,
+            AbsoluteLength::Rems(rems) => rems * rem_size,
+        }
+    }
+}
+
+impl Default for AbsoluteLength {
+    fn default() -> Self {
+        Self::Pixels(0.0)
+    }
+}
+
+/// A non-auto length that can be defined in pixels, rems, or percent of parent.
+#[derive(Clone, Copy)]
+pub enum DefiniteLength {
+    Absolute(AbsoluteLength),
+    Relative(f32), // Percent, from 0 to 100.
+}
+
+impl DefiniteLength {
+    fn to_taffy(&self, rem_size: f32) -> taffy::style::LengthPercentage {
+        match self {
+            DefiniteLength::Absolute(length) => match length {
+                AbsoluteLength::Pixels(pixels) => taffy::style::LengthPercentage::Length(*pixels),
+                AbsoluteLength::Rems(rems) => {
+                    taffy::style::LengthPercentage::Length(rems * rem_size)
+                }
+            },
+            DefiniteLength::Relative(fraction) => {
+                taffy::style::LengthPercentage::Percent(*fraction)
+            }
+        }
+    }
+}
+
+impl From<AbsoluteLength> for DefiniteLength {
+    fn from(length: AbsoluteLength) -> Self {
+        Self::Absolute(length)
+    }
+}
+
+impl Default for DefiniteLength {
+    fn default() -> Self {
+        Self::Absolute(AbsoluteLength::default())
+    }
+}
+
+/// A length that can be defined in pixels, rems, percent of parent, or auto.
+#[derive(Clone, Copy)]
+pub enum Length {
+    Definite(DefiniteLength),
+    Auto,
+}
+
+pub fn relative<T: From<DefiniteLength>>(fraction: f32) -> T {
+    DefiniteLength::Relative(fraction).into()
+}
+
+pub fn rems<T: From<AbsoluteLength>>(rems: f32) -> T {
+    AbsoluteLength::Rems(rems).into()
+}
+
+pub fn pixels<T: From<AbsoluteLength>>(pixels: f32) -> T {
+    AbsoluteLength::Pixels(pixels).into()
+}
+
+pub fn auto() -> Length {
+    Length::Auto
+}
+
+impl Length {
+    pub fn to_taffy(&self, rem_size: f32) -> taffy::prelude::LengthPercentageAuto {
+        match self {
+            Length::Definite(length) => length.to_taffy(rem_size).into(),
+            Length::Auto => taffy::prelude::LengthPercentageAuto::Auto,
+        }
+    }
+}
+
+impl From<DefiniteLength> for Length {
+    fn from(length: DefiniteLength) -> Self {
+        Self::Definite(length)
+    }
+}
+
+impl From<AbsoluteLength> for Length {
+    fn from(length: AbsoluteLength) -> Self {
+        Self::Definite(length.into())
+    }
+}
+
+impl Default for Length {
+    fn default() -> Self {
+        Self::Definite(DefiniteLength::default())
+    }
+}

crates/gpui/src/gpui.rs

@@ -27,7 +27,10 @@ pub mod json;
 pub mod keymap_matcher;
 pub mod platform;
 pub use gpui_macros::{test, Element};
-pub use window::{Axis, RectFExt, SizeConstraint, Vector2FExt, WindowContext};
+pub use window::{
+    Axis, EngineLayout, LayoutEngine, LayoutId, RectFExt, SizeConstraint, Vector2FExt,
+    WindowContext,
+};
 
 pub use anyhow;
 pub use serde_json;

crates/gpui/src/platform.rs

@@ -192,7 +192,7 @@ impl<'a> WindowOptions<'a> {
     }
 }
 
-#[derive(Debug)]
+#[derive(Debug, Default)]
 pub struct TitlebarOptions<'a> {
     pub title: Option<&'a str>,
     pub appears_transparent: bool,

crates/gpui/src/platform/event.rs

@@ -1,4 +1,4 @@
-use std::ops::Deref;
+use std::{any::Any, ops::Deref};
 
 use pathfinder_geometry::vector::vec2f;
 
@@ -142,6 +142,7 @@ pub struct MouseButtonEvent {
     pub position: Vector2F,
     pub modifiers: Modifiers,
     pub click_count: usize,
+    pub is_down: bool,
 }
 
 impl Deref for MouseButtonEvent {
@@ -174,6 +175,7 @@ impl MouseMovedEvent {
             button: self.pressed_button.unwrap_or(button),
             modifiers: self.modifiers,
             click_count: 0,
+            is_down: self.pressed_button.is_some(),
         }
     }
 }
@@ -211,10 +213,24 @@ impl Event {
             Event::KeyDown { .. } => None,
             Event::KeyUp { .. } => None,
             Event::ModifiersChanged { .. } => None,
-            Event::MouseDown(event) | Event::MouseUp(event) => Some(event.position),
+            Event::MouseDown(event) => Some(event.position),
+            Event::MouseUp(event) => Some(event.position),
             Event::MouseMoved(event) => Some(event.position),
             Event::MouseExited(event) => Some(event.position),
             Event::ScrollWheel(event) => Some(event.position),
         }
     }
+
+    pub fn mouse_event<'a>(&'a self) -> Option<&'a dyn Any> {
+        match self {
+            Event::KeyDown { .. } => None,
+            Event::KeyUp { .. } => None,
+            Event::ModifiersChanged { .. } => None,
+            Event::MouseDown(event) => Some(event),
+            Event::MouseUp(event) => Some(event),
+            Event::MouseMoved(event) => Some(event),
+            Event::MouseExited(event) => Some(event),
+            Event::ScrollWheel(event) => Some(event),
+        }
+    }
 }

crates/gpui/src/platform/mac/event.rs

@@ -132,6 +132,7 @@ impl Event {
                         ),
                         modifiers: read_modifiers(native_event),
                         click_count: native_event.clickCount() as usize,
+                        is_down: true,
                     })
                 })
             }
@@ -158,6 +159,7 @@ impl Event {
                         ),
                         modifiers: read_modifiers(native_event),
                         click_count: native_event.clickCount() as usize,
+                        is_down: false,
                     })
                 })
             }

crates/gpui/src/scene.rs

@@ -1,5 +1,6 @@
 mod mouse_event;
 mod mouse_region;
+mod region;
 
 #[cfg(debug_assertions)]
 use collections::HashSet;
@@ -8,7 +9,12 @@ use schemars::JsonSchema;
 use serde::Deserialize;
 use serde_derive::Serialize;
 use serde_json::json;
-use std::{borrow::Cow, sync::Arc};
+use std::{
+    any::{Any, TypeId},
+    borrow::Cow,
+    rc::Rc,
+    sync::Arc,
+};
 
 use crate::{
     color::Color,
@@ -16,7 +22,7 @@ use crate::{
     geometry::{rect::RectF, vector::Vector2F},
     json::ToJson,
     platform::{current::Surface, CursorStyle},
-    ImageData,
+    ImageData, WindowContext,
 };
 pub use mouse_event::*;
 pub use mouse_region::*;
@@ -25,6 +31,8 @@ pub struct SceneBuilder {
     scale_factor: f32,
     stacking_contexts: Vec<StackingContext>,
     active_stacking_context_stack: Vec<usize>,
+    /// Used by the playground crate.
+    pub event_handlers: Vec<EventHandler>,
     #[cfg(debug_assertions)]
     mouse_region_ids: HashSet<MouseRegionId>,
 }
@@ -32,6 +40,7 @@ pub struct SceneBuilder {
 pub struct Scene {
     scale_factor: f32,
     stacking_contexts: Vec<StackingContext>,
+    event_handlers: Vec<EventHandler>,
 }
 
 struct StackingContext {
@@ -272,6 +281,12 @@ impl Scene {
             })
             .collect()
     }
+
+    pub fn take_event_handlers(&mut self) -> Vec<EventHandler> {
+        self.event_handlers
+            .sort_by(|a, b| a.order.cmp(&b.order).reverse());
+        std::mem::take(&mut self.event_handlers)
+    }
 }
 
 impl SceneBuilder {
@@ -283,6 +298,7 @@ impl SceneBuilder {
             active_stacking_context_stack: vec![0],
             #[cfg(debug_assertions)]
             mouse_region_ids: Default::default(),
+            event_handlers: Vec::new(),
         }
     }
 
@@ -292,6 +308,7 @@ impl SceneBuilder {
         Scene {
             scale_factor: self.scale_factor,
             stacking_contexts: self.stacking_contexts,
+            event_handlers: self.event_handlers,
         }
     }
 
@@ -688,6 +705,13 @@ impl MouseRegion {
     }
 }
 
+pub struct EventHandler {
+    pub order: u32,
+    // The &dyn Any parameter below expects an event.
+    pub handler: Rc<dyn Fn(&dyn Any, &mut WindowContext) -> bool>,
+    pub event_type: TypeId,
+}
+
 fn can_draw(bounds: RectF) -> bool {
     let size = bounds.size();
     size.x() > 0. && size.y() > 0.

crates/gpui/src/scene/mouse_region.rs

@@ -1,6 +1,4 @@
-use crate::{
+use crate::{platform::MouseButton, window::WindowContext, EventContext, TypeTag, ViewContext};
-    platform::MouseButton, window::WindowContext, EventContext, TypeTag, View, ViewContext,
-};
 use collections::HashMap;
 use pathfinder_geometry::rect::RectF;
 use smallvec::SmallVec;
@@ -72,7 +70,7 @@ impl MouseRegion {
 
     pub fn on_down<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseDown, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_down(button, handler);
@@ -81,7 +79,7 @@ impl MouseRegion {
 
     pub fn on_up<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseUp, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_up(button, handler);
@@ -90,7 +88,7 @@ impl MouseRegion {
 
     pub fn on_click<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseClick, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_click(button, handler);
@@ -99,7 +97,7 @@ impl MouseRegion {
 
     pub fn on_click_out<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseClickOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_click_out(button, handler);
@@ -108,7 +106,7 @@ impl MouseRegion {
 
     pub fn on_down_out<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseDownOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_down_out(button, handler);
@@ -117,7 +115,7 @@ impl MouseRegion {
 
     pub fn on_up_out<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseUpOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_up_out(button, handler);
@@ -126,7 +124,7 @@ impl MouseRegion {
 
     pub fn on_drag<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseDrag, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_drag(button, handler);
@@ -135,7 +133,7 @@ impl MouseRegion {
 
     pub fn on_hover<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseHover, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_hover(handler);
@@ -144,7 +142,7 @@ impl MouseRegion {
 
     pub fn on_move<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseMove, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_move(handler);
@@ -153,7 +151,7 @@ impl MouseRegion {
 
     pub fn on_move_out<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseMoveOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_move_out(handler);
@@ -162,7 +160,7 @@ impl MouseRegion {
 
     pub fn on_scroll<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseScrollWheel, &mut V, &mut EventContext<V>) + 'static,
     {
         self.handlers = self.handlers.on_scroll(handler);
@@ -314,7 +312,7 @@ impl HandlerSet {
 
     pub fn on_move<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseMove, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::move_disc(), None,
@@ -336,7 +334,7 @@ impl HandlerSet {
 
     pub fn on_move_out<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseMoveOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::move_out_disc(), None,
@@ -358,7 +356,7 @@ impl HandlerSet {
 
     pub fn on_down<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseDown, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::down_disc(), Some(button),
@@ -380,7 +378,7 @@ impl HandlerSet {
 
     pub fn on_up<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseUp, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::up_disc(), Some(button),
@@ -402,7 +400,7 @@ impl HandlerSet {
 
     pub fn on_click<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseClick, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::click_disc(), Some(button),
@@ -424,7 +422,7 @@ impl HandlerSet {
 
     pub fn on_click_out<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseClickOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::click_out_disc(), Some(button),
@@ -446,7 +444,7 @@ impl HandlerSet {
 
     pub fn on_down_out<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseDownOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::down_out_disc(), Some(button),
@@ -468,7 +466,7 @@ impl HandlerSet {
 
     pub fn on_up_out<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseUpOut, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::up_out_disc(), Some(button),
@@ -490,7 +488,7 @@ impl HandlerSet {
 
     pub fn on_drag<V, F>(mut self, button: MouseButton, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseDrag, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::drag_disc(), Some(button),
@@ -512,7 +510,7 @@ impl HandlerSet {
 
     pub fn on_hover<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseHover, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::hover_disc(), None,
@@ -534,7 +532,7 @@ impl HandlerSet {
 
     pub fn on_scroll<V, F>(mut self, handler: F) -> Self
     where
-        V: View,
+        V: 'static,
         F: Fn(MouseScrollWheel, &mut V, &mut EventContext<V>) + 'static,
     {
         self.insert(MouseEvent::scroll_wheel_disc(), None,

crates/gpui/src/scene/region.rs

@@ -0,0 +1,7 @@
+// use crate::geometry::rect::RectF;
+// use crate::WindowContext;
+
+// struct Region {
+//     pub bounds: RectF,
+//     pub click_handler: Option<Rc<dyn Fn(&dyn Any, MouseEvent, &mut WindowContext)>>,
+// }

crates/gpui/src/text_layout.rs

@@ -212,7 +212,7 @@ pub struct Glyph {
 }
 
 impl Line {
-    fn new(layout: Arc<LineLayout>, runs: &[(usize, RunStyle)]) -> Self {
+    pub fn new(layout: Arc<LineLayout>, runs: &[(usize, RunStyle)]) -> Self {
         let mut style_runs = SmallVec::new();
         for (len, style) in runs {
             style_runs.push(StyleRun {

crates/gpui/tests/test.rs

@@ -1,14 +1,14 @@
-use gpui::{elements::RenderElement, View, ViewContext};
+use gpui::{elements::Empty, Element, ViewContext};
-use gpui_macros::Element;
+// use gpui_macros::Element;
 
 #[test]
 fn test_derive_render_element() {
     #[derive(Element)]
     struct TestElement {}
 
-    impl RenderElement for TestElement {
+    impl TestElement {
-        fn render<V: View>(&mut self, _: &mut V, _: &mut ViewContext<V>) -> gpui::AnyElement<V> {
+        fn render<V: 'static>(&mut self, _: &mut V, _: &mut ViewContext<V>) -> impl Element<V> {
-            unimplemented!()
+            Empty::new()
         }
     }
 }

crates/gpui_macros/Cargo.toml

@@ -10,6 +10,7 @@ proc-macro = true
 doctest = false
 
 [dependencies]
+lazy_static.workspace = true
+proc-macro2 = "1.0"
 syn = "1.0"
 quote = "1.0"
-proc-macro2 = "1.0"

crates/gpui_macros/src/gpui_macros.rs

@@ -4,7 +4,7 @@ use quote::{format_ident, quote};
 use std::mem;
 use syn::{
     parse_macro_input, parse_quote, spanned::Spanned as _, AttributeArgs, DeriveInput, FnArg,
-    ItemFn, Lit, Meta, NestedMeta, Type,
+    GenericParam, Generics, ItemFn, Lit, Meta, NestedMeta, Type, WhereClause,
 };
 
 #[proc_macro_attribute]
@@ -278,18 +278,44 @@ fn parse_bool(literal: &Lit) -> Result<bool, TokenStream> {
 
 #[proc_macro_derive(Element)]
 pub fn element_derive(input: TokenStream) -> TokenStream {
-    // Parse the input tokens into a syntax tree
+    let ast = parse_macro_input!(input as DeriveInput);
-    let input = parse_macro_input!(input as DeriveInput);
+    let type_name = ast.ident;
 
-    // The name of the struct/enum
+    let placeholder_view_generics: Generics = parse_quote! { <V: 'static> };
-    let name = input.ident;
+    let placeholder_view_type_name: Ident = parse_quote! { V };
-    let must_implement = format_ident!("{}MustImplementRenderElement", name);
+    let view_type_name: Ident;
+    let impl_generics: syn::ImplGenerics<'_>;
+    let type_generics: Option<syn::TypeGenerics<'_>>;
+    let where_clause: Option<&'_ WhereClause>;
 
-    let expanded = quote! {
+    match ast.generics.params.iter().find_map(|param| {
-        trait #must_implement : gpui::elements::RenderElement {}
+        if let GenericParam::Type(type_param) = param {
-        impl #must_implement for #name {}
+            Some(type_param.ident.clone())
+        } else {
+            None
+        }
+    }) {
+        Some(type_name) => {
+            view_type_name = type_name;
+            let generics = ast.generics.split_for_impl();
+            impl_generics = generics.0;
+            type_generics = Some(generics.1);
+            where_clause = generics.2;
+        }
+        _ => {
+            view_type_name = placeholder_view_type_name;
+            let generics = placeholder_view_generics.split_for_impl();
+            impl_generics = generics.0;
+            type_generics = None;
+            where_clause = generics.2;
+        }
+    }
+
+    let gen = quote! {
+        impl #impl_generics Element<#view_type_name> for #type_name #type_generics
+        #where_clause
+        {
 
-        impl<V: gpui::View> gpui::elements::Element<V> for #name {
             type LayoutState = gpui::elements::AnyElement<V>;
             type PaintState = ();
 
@@ -299,7 +325,7 @@ pub fn element_derive(input: TokenStream) -> TokenStream {
                 view: &mut V,
                 cx: &mut gpui::LayoutContext<V>,
             ) -> (gpui::geometry::vector::Vector2F, gpui::elements::AnyElement<V>) {
-                let mut element = self.render(view, cx);
+                let mut element = self.render(view, cx).into_any();
                 let size = element.layout(constraint, view, cx);
                 (size, element)
             }
@@ -336,11 +362,11 @@ pub fn element_derive(input: TokenStream) -> TokenStream {
                 _: &(),
                 view: &V,
                 cx: &gpui::ViewContext<V>,
-            ) -> gpui::serde_json::Value {
+            ) -> gpui::json::Value {
                 element.debug(view, cx)
             }
         }
     };
-    // Return generated code
+
-    TokenStream::from(expanded)
+    gen.into()
 }

crates/language/src/buffer.rs

@@ -2192,13 +2192,16 @@ impl BufferSnapshot {
         let mut end = start;
         let mut next_chars = self.chars_at(start).peekable();
         let mut prev_chars = self.reversed_chars_at(start).peekable();
+
+        let language = self.language_at(start);
+        let kind = |c| char_kind(language, c);
         let word_kind = cmp::max(
-            prev_chars.peek().copied().map(char_kind),
+            prev_chars.peek().copied().map(kind),
-            next_chars.peek().copied().map(char_kind),
+            next_chars.peek().copied().map(kind),
         );
 
         for ch in prev_chars {
-            if Some(char_kind(ch)) == word_kind && ch != '\n' {
+            if Some(kind(ch)) == word_kind && ch != '\n' {
                 start -= ch.len_utf8();
             } else {
                 break;
@@ -2206,7 +2209,7 @@ impl BufferSnapshot {
         }
 
         for ch in next_chars {
-            if Some(char_kind(ch)) == word_kind && ch != '\n' {
+            if Some(kind(ch)) == word_kind && ch != '\n' {
                 end += ch.len_utf8();
             } else {
                 break;
@@ -3003,14 +3006,18 @@ pub fn contiguous_ranges(
     })
 }
 
-pub fn char_kind(c: char) -> CharKind {
+pub fn char_kind(language: Option<&Arc<Language>>, c: char) -> CharKind {
     if c.is_whitespace() {
-        CharKind::Whitespace
+        return CharKind::Whitespace;
     } else if c.is_alphanumeric() || c == '_' {
-        CharKind::Word
+        return CharKind::Word;
-    } else {
-        CharKind::Punctuation
     }
+    if let Some(language) = language {
+        if language.config.word_characters.contains(&c) {
+            return CharKind::Word;
+        }
+    }
+    CharKind::Punctuation
 }
 
 /// Find all of the ranges of whitespace that occur at the ends of lines

crates/language/src/language.rs

@@ -11,7 +11,7 @@ mod buffer_tests;
 
 use anyhow::{anyhow, Context, Result};
 use async_trait::async_trait;
-use collections::HashMap;
+use collections::{HashMap, HashSet};
 use futures::{
     channel::oneshot,
     future::{BoxFuture, Shared},
@@ -344,6 +344,8 @@ pub struct LanguageConfig {
     pub block_comment: Option<(Arc<str>, Arc<str>)>,
     #[serde(default)]
     pub overrides: HashMap<String, LanguageConfigOverride>,
+    #[serde(default)]
+    pub word_characters: HashSet<char>,
 }
 
 #[derive(Debug, Default)]
@@ -411,6 +413,7 @@ impl Default for LanguageConfig {
             block_comment: Default::default(),
             overrides: Default::default(),
             collapsed_placeholder: Default::default(),
+            word_characters: Default::default(),
         }
     }
 }

crates/language_tools/src/lsp_log.rs

@@ -450,7 +450,7 @@ impl View for LspLogView {
 }
 
 impl Item for LspLogView {
-    fn tab_content<V: View>(
+    fn tab_content<V: 'static>(
         &self,
         _: Option<usize>,
         style: &theme::Tab,

crates/language_tools/src/syntax_tree_view.rs

@@ -373,6 +373,7 @@ impl View for SyntaxTreeView {
             font_size,
             font_properties: Default::default(),
             underline: Default::default(),
+            soft_wrap: false,
         };
 
         let line_height = cx.font_cache().line_height(font_size);
@@ -451,7 +452,7 @@ impl View for SyntaxTreeView {
 }
 
 impl Item for SyntaxTreeView {
-    fn tab_content<V: View>(
+    fn tab_content<V: 'static>(
         &self,
         _: Option<usize>,
         style: &theme::Tab,

crates/project/src/project.rs

@@ -5180,7 +5180,7 @@ impl Project {
                                         snapshot.file().map(|file| file.path().as_ref()),
                                     ) {
                                         query
-                                            .search(snapshot.as_rope())
+                                            .search(&snapshot, None)
                                             .await
                                             .iter()
                                             .map(|range| {

crates/project/src/search.rs

@@ -3,7 +3,7 @@ use anyhow::{Context, Result};
 use client::proto;
 use globset::{Glob, GlobMatcher};
 use itertools::Itertools;
-use language::{char_kind, Rope};
+use language::{char_kind, BufferSnapshot};
 use regex::{Regex, RegexBuilder};
 use smol::future::yield_now;
 use std::{
@@ -39,6 +39,7 @@ pub enum SearchQuery {
         case_sensitive: bool,
         inner: SearchInputs,
     },
+
     Regex {
         regex: Regex,
 
@@ -214,12 +215,24 @@ impl SearchQuery {
         }
     }
 
-    pub async fn search(&self, rope: &Rope) -> Vec<Range<usize>> {
+    pub async fn search(
+        &self,
+        buffer: &BufferSnapshot,
+        subrange: Option<Range<usize>>,
+    ) -> Vec<Range<usize>> {
         const YIELD_INTERVAL: usize = 20000;
 
         if self.as_str().is_empty() {
             return Default::default();
         }
+        let language = buffer.language_at(0);
+        let rope = if let Some(range) = subrange {
+            buffer.as_rope().slice(range)
+        } else {
+            buffer.as_rope().clone()
+        };
+
+        let kind = |c| char_kind(language, c);
 
         let mut matches = Vec::new();
         match self {
@@ -236,10 +249,10 @@ impl SearchQuery {
 
                     let mat = mat.unwrap();
                     if *whole_word {
-                        let prev_kind = rope.reversed_chars_at(mat.start()).next().map(char_kind);
+                        let prev_kind = rope.reversed_chars_at(mat.start()).next().map(kind);
-                        let start_kind = char_kind(rope.chars_at(mat.start()).next().unwrap());
+                        let start_kind = kind(rope.chars_at(mat.start()).next().unwrap());
-                        let end_kind = char_kind(rope.reversed_chars_at(mat.end()).next().unwrap());
+                        let end_kind = kind(rope.reversed_chars_at(mat.end()).next().unwrap());
-                        let next_kind = rope.chars_at(mat.end()).next().map(char_kind);
+                        let next_kind = rope.chars_at(mat.end()).next().map(kind);
                         if Some(start_kind) == prev_kind || Some(end_kind) == next_kind {
                             continue;
                         }
@@ -247,6 +260,7 @@ impl SearchQuery {
                     matches.push(mat.start()..mat.end())
                 }
             }
+
             Self::Regex {
                 regex, multiline, ..
             } => {
@@ -284,6 +298,7 @@ impl SearchQuery {
                 }
             }
         }
+
         matches
     }
 

crates/project_panel/src/project_panel.rs

@@ -1320,7 +1320,7 @@ impl ProjectPanel {
         }
     }
 
-    fn render_entry_visual_element<V: View>(
+    fn render_entry_visual_element<V: 'static>(
         details: &EntryDetails,
         editor: Option<&ViewHandle<Editor>>,
         padding: f32,

crates/recent_projects/src/highlighted_workspace_location.rs

@@ -3,7 +3,7 @@ use std::path::Path;
 use fuzzy::StringMatch;
 use gpui::{
     elements::{Label, LabelStyle},
-    AnyElement, Element, View,
+    AnyElement, Element,
 };
 use util::paths::PathExt;
 use workspace::WorkspaceLocation;
@@ -43,7 +43,7 @@ impl HighlightedText {
         }
     }
 
-    pub fn render<V: View>(self, style: impl Into<LabelStyle>) -> AnyElement<V> {
+    pub fn render<V: 'static>(self, style: impl Into<LabelStyle>) -> AnyElement<V> {
         Label::new(self.text, style)
             .with_highlights(self.highlight_positions)
             .into_any()