Add IDE Readme (#1678)

* Add .vscode settings that are useful for making it easier to build

* Ignore the extension output

* Add a README that describes how to start the IDE

README.md

@@ -1 +1,27 @@
-A lightweight, extensible base for LSP IDE tooling based on Shake and GHC Lib
+# Haskell IDE Core
+
+Our vision is that you should build an IDE by combining:
+
+* [hie-bios](https://github.com/mpickering/haskell-ide-engine/tree/hie-bios/hie-bios) for determining where your files are, what the dependencies, what extensions are enabled etc.
+* `haskell-ide-core` - this library - for defining how to type check, when to type check, and producing messages.
+* `haskell-lsp` for sending those messages to an LSP server.
+* A VS Code extension, e.g. `extension` in this directory.
+
+There are more details [in this blog post](https://4ta.uk/p/shaking-up-the-ide).
+
+## How to use it
+
+Let's assume you want to load the `haskell-ide-core` source code in a VS Code IDE.
+
+1. `git clone https://github.com/digital-asset/daml.git`
+2. `cd compiler/haskell-ide-core`
+3. `stack build`
+4. `cd extension`
+5. `npm install`
+6. `code .`
+7. Press F5 to start the extension.
+8. In the spawned extension, open the folder `haskell-ide-core`.
+9. In the preferences, set the Haskell IDE Core executable preference to `stack` and the arguments to `exec -- ide-demo --ide .ghci`
+10. Run the Reload Window command in VS Code.
+
+Now you should have a working IDE dealing with itself.

extension/.vscode/extensions.json

@@ -0,0 +1,7 @@
+{
+	// See http://go.microsoft.com/fwlink/?LinkId=827846
+	// for the documentation about the extensions.json format
+	"recommendations": [
+		"ms-vscode.vscode-typescript-tslint-plugin"
+	]
+}

extension/.vscode/launch.json

@@ -0,0 +1,35 @@
+// A launch configuration that compiles the extension and then opens it inside a new window
+// Use IntelliSense to learn about possible attributes.
+// Hover to view descriptions of existing attributes.
+// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+{
+	"version": "0.2.0",
+	"configurations": [{
+			"name": "Run Extension",
+			"type": "extensionHost",
+			"request": "launch",
+			"runtimeExecutable": "${execPath}",
+			"args": [
+				"--extensionDevelopmentPath=${workspaceFolder}"
+			],
+			"outFiles": [
+				"${workspaceFolder}/out/**/*.js"
+			],
+			"preLaunchTask": "npm: watch"
+		},
+		{
+			"name": "Extension Tests",
+			"type": "extensionHost",
+			"request": "launch",
+			"runtimeExecutable": "${execPath}",
+			"args": [
+				"--extensionDevelopmentPath=${workspaceFolder}",
+				"--extensionTestsPath=${workspaceFolder}/out/test"
+			],
+			"outFiles": [
+				"${workspaceFolder}/out/test/**/*.js"
+			],
+			"preLaunchTask": "npm: watch"
+		}
+	]
+}

extension/.vscode/settings.json

@@ -0,0 +1,11 @@
+// Place your settings in this file to overwrite default and user settings.
+{
+    "files.exclude": {
+        "out": false // set this to true to hide the "out" folder with the compiled JS files
+    },
+    "search.exclude": {
+        "out": true // set this to false to include "out" folder in search results
+    },
+    // Turn off tsc task auto detection since we have the necessary tasks as npm scripts
+    "typescript.tsc.autoDetect": "off"
+}

extension/.vscode/tasks.json

@@ -0,0 +1,20 @@
+// See https://go.microsoft.com/fwlink/?LinkId=733558
+// for the documentation about the tasks.json format
+{
+	"version": "2.0.0",
+	"tasks": [
+		{
+			"type": "npm",
+			"script": "watch",
+			"problemMatcher": "$tsc-watch",
+			"isBackground": true,
+			"presentation": {
+				"reveal": "never"
+			},
+			"group": {
+				"kind": "build",
+				"isDefault": true
+			}
+		}
+	]
+}