From cb4da18021a33a2ece255cfbdd147b8f90856f3b Mon Sep 17 00:00:00 2001
From: Wez Furlong <wez@wezfurlong.org>
Date: Sat, 29 May 2021 12:39:13 -0700
Subject: [PATCH] key assignment and docs for ShowDebugOverlay

refs: https://github.com/wez/wezterm/issues/641
---
 config/src/keyassignment.rs                       |  1 +
 docs/changelog.md                                 |  1 +
 docs/config/keys.md                               |  1 +
 docs/config/lua/keyassignment/ShowDebugOverlay.md | 15 +++++++++++++++
 wezterm-gui/src/overlay/debug.rs                  |  4 +++-
 5 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 docs/config/lua/keyassignment/ShowDebugOverlay.md

diff --git a/config/src/keyassignment.rs b/config/src/keyassignment.rs
index e0a1c802c..c15feaa27 100644
--- a/config/src/keyassignment.rs
+++ b/config/src/keyassignment.rs
@@ -301,6 +301,7 @@ impl InputMap {
                     KeyCode::Char('F'),
                     Search(Pattern::CaseSensitiveString("".into()))
                 ],
+                [Modifiers::CTRL, KeyCode::Char('L'), ShowDebugOverlay],
                 [ctrl_shift, KeyCode::Char(' '), QuickSelect],
                 // Font size manipulation
                 [Modifiers::CTRL, KeyCode::Char('-'), DecreaseFontSize],
diff --git a/docs/changelog.md b/docs/changelog.md
index c20234361..d1ebedd74 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -34,6 +34,7 @@ As features stabilize some brief notes about them will accumulate here.
 * Fixed: splitting panes in multiplexer could fail after a network reconnect [#781](https://github.com/wez/wezterm/issues/781)
 * Fixed: multiplexer now propagates toast notifications and color palette to client [#489](https://github.com/wez/wezterm/issues/489) [#748](https://github.com/wez/wezterm/issues/748)
 * Fixed: neovim interprets drags as double clicks [#823](https://github.com/wez/wezterm/discussions/823)
+* New: `CTRL+SHIFT+L` is assigned to [ShowDebugOverlay](config/lua/keyassignment/ShowDebugOverlay.md) [#641](https://github.com/wez/wezterm/issues/641)
 
 ### 20210502-154244-3f7122cb
 
diff --git a/docs/config/keys.md b/docs/config/keys.md
index 19aa22d9b..022aca198 100644
--- a/docs/config/keys.md
+++ b/docs/config/keys.md
@@ -169,6 +169,7 @@ The default key bindings are:
 | `SUPER`          | `h`    | `HideApplication` (macOS only) |
 | `SUPER`          | `k`    | `ClearScrollback="ScrollbackOnly"` |
 | `CTRL+SHIFT`     | `K`    | `ClearScrollback="ScrollbackOnly"` |
+| `CTRL+SHIFT`     | `L`    | `ShowDebugOverlay` (*since: nightly builds only*)|
 | `SUPER`          | `f`    | `Search={CaseSensitiveString=""}` |
 | `CTRL+SHIFT`     | `F`    | `Search={CaseSensitiveString=""}` |
 | `CTRL+SHIFT`     | `X`    | `ActivateCopyMode` |
diff --git a/docs/config/lua/keyassignment/ShowDebugOverlay.md b/docs/config/lua/keyassignment/ShowDebugOverlay.md
new file mode 100644
index 000000000..5af1c569d
--- /dev/null
+++ b/docs/config/lua/keyassignment/ShowDebugOverlay.md
@@ -0,0 +1,15 @@
+# `ShowDebugOverlay`
+
+*Since: nightly builds only*
+
+Overlays the current tab with the debug overlay, which is a combination
+of a debug log and a lua [REPL](https://en.wikipedia.org/wiki/Read%E2%80%93eval%E2%80%93print_loop).
+
+The REPL has the following globals available:
+
+* `wezterm` - the [wezterm](../wezterm/index.md) module is pre-imported
+* `window` - the [window](../window/index.md) object for the current window
+
+The lua context in the REPL is not connected to any global state; you cannot use it
+to dynamically assign event handlers for example.  It is primarily useful for
+prototyping lua snippets before you integrate them fully into your config.
diff --git a/wezterm-gui/src/overlay/debug.rs b/wezterm-gui/src/overlay/debug.rs
index aa1cee057..f378c7619 100644
--- a/wezterm-gui/src/overlay/debug.rs
+++ b/wezterm-gui/src/overlay/debug.rs
@@ -131,10 +131,12 @@ pub fn show_debug_overlay(mut term: TermWizTerminal, gui_win: GuiWin) -> anyhow:
 
     loop {
         print_new_log_entries(&mut term, &mut latest_log_entry)?;
-
         let mut editor = LineEditor::new(&mut term);
         editor.set_prompt("> ");
         if let Some(line) = editor.read_line(&mut host)? {
+            if line.is_empty() {
+                continue;
+            }
             host.history().add(&line);
 
             let expr = format!("return {}", line);