Merge #4366

4366: Unified debug lens r=matklad a=vsrs

Right now every debug engine gets the debug executable and exports the errors on its own.

This PR unifies the way all engines work. And adds an option to configure each engine separably.
For example, this adds visualizers for both `CodeLLDB` and `C++ tools Windows debugger`
```json
"rust-analyzer.debug.engineSettings": {
    "cppvsdbg": {
        "visualizerFile": "${workspaceRoot}/rdisk.natvis"
    },
    "lldb": {
        "initCommands": [
            "command script import ${workspaceRoot}/rdisk.vis.py"
        ]
    }
}
```

Co-authored-by: vsrs <[email protected]>
Co-authored-by: vsrs <[email protected]>

3 files changed, 60 insertions, 32 deletions

diff --git a/editors/code/package.json b/editors/code/package.json
index 853fc513b..c6fc13519 100644
--- a/editors/code/package.json
+++ b/editors/code/package.json
@@ -423,6 +423,16 @@
                     "default": {
                         "/rustc/<id>": "${env:USERPROFILE}/.rustup/toolchains/<toolchain-id>/lib/rustlib/src/rust"
                     }
+                },
+                "rust-analyzer.debug.openDebugPane": {
+                    "description": "Whether to open up the Debug Pane on debugging start.",
+                    "type": "boolean",
+                    "default": false
+                },
+                "rust-analyzer.debug.engineSettings": {
+                    "type": "object",
+                    "default": {},
+                    "description": "Optional settings passed to the debug engine. Example:\n{ \"lldb\": { \"terminal\":\"external\"} }"
                 }
             }
         },
diff --git a/editors/code/src/commands/runnables.ts b/editors/code/src/commands/runnables.ts
index 2ed150e25..ae328d2a4 100644
--- a/editors/code/src/commands/runnables.ts
+++ b/editors/code/src/commands/runnables.ts
@@ -64,29 +64,20 @@ export function runSingle(ctx: Ctx): Cmd {
     };
 }
 
-function getLldbDebugConfig(config: ra.Runnable, sourceFileMap: Record<string, string>): vscode.DebugConfiguration {
+function getLldbDebugConfig(config: ra.Runnable, executable: string, sourceFileMap?: Record<string, string>): vscode.DebugConfiguration {
     return {
         type: "lldb",
         request: "launch",
         name: config.label,
-        cargo: {
-            args: config.args,
-        },
+        program: executable,
         args: config.extraArgs,
         cwd: config.cwd,
-        sourceMap: sourceFileMap
+        sourceMap: sourceFileMap,
+        sourceLanguages: ["rust"]
     };
 }
 
-const debugOutput = vscode.window.createOutputChannel("Debug");
-
-async function getCppvsDebugConfig(config: ra.Runnable, sourceFileMap: Record<string, string>): Promise<vscode.DebugConfiguration> {
-    debugOutput.clear();
-
-    const cargo = new Cargo(config.cwd || '.', debugOutput);
-    const executable = await cargo.executableFromArgs(config.args);
-
-    // if we are here, there were no compilation errors.
+function getCppvsDebugConfig(config: ra.Runnable, executable: string, sourceFileMap?: Record<string, string>): vscode.DebugConfiguration {
     return {
         type: (os.platform() === "win32") ? "cppvsdbg" : 'cppdbg',
         request: "launch",
@@ -98,39 +89,62 @@ async function getCppvsDebugConfig(config: ra.Runnable, sourceFileMap: Record<st
     };
 }
 
+const debugOutput = vscode.window.createOutputChannel("Debug");
+
+async function getDebugExecutable(config: ra.Runnable): Promise<string> {
+    const cargo = new Cargo(config.cwd || '.', debugOutput);
+    const executable = await cargo.executableFromArgs(config.args);
+
+    // if we are here, there were no compilation errors.
+    return executable;
+}
+
+type DebugConfigProvider = (config: ra.Runnable, executable: string, sourceFileMap?: Record<string, string>) => vscode.DebugConfiguration;
+
 export function debugSingle(ctx: Ctx): Cmd {
     return async (config: ra.Runnable) => {
         const editor = ctx.activeRustEditor;
         if (!editor) return;
 
-        const lldbId = "vadimcn.vscode-lldb";
-        const cpptoolsId = "ms-vscode.cpptools";
+        const knownEngines: Record<string, DebugConfigProvider> = {
+            "vadimcn.vscode-lldb": getLldbDebugConfig,
+            "ms-vscode.cpptools": getCppvsDebugConfig
+        };
+        const debugOptions = ctx.config.debug;
 
-        const debugEngineId = ctx.config.debug.engine;
         let debugEngine = null;
-        if (debugEngineId === "auto") {
-            debugEngine = vscode.extensions.getExtension(lldbId);
-            if (!debugEngine) {
-                debugEngine = vscode.extensions.getExtension(cpptoolsId);
+        if (debugOptions.engine === "auto") {
+            for (var engineId in knownEngines) {
+                debugEngine = vscode.extensions.getExtension(engineId);
+                if (debugEngine) break;
             }
         }
         else {
-            debugEngine = vscode.extensions.getExtension(debugEngineId);
+            debugEngine = vscode.extensions.getExtension(debugOptions.engine);
         }
 
         if (!debugEngine) {
-            vscode.window.showErrorMessage(
-                `Install [CodeLLDB](https://marketplace.visualstudio.com/items?itemName=${lldbId}) ` +
-                `or [MS C++ tools](https://marketplace.visualstudio.com/items?itemName=${cpptoolsId}) ` +
-                `extension for debugging.`
-            );
+            vscode.window.showErrorMessage(`Install [CodeLLDB](https://marketplace.visualstudio.com/items?itemName=vadimcn.vscode-lldb)`
+                + ` or [MS C++ tools](https://marketplace.visualstudio.com/items?itemName=ms-vscode.cpptools) extension for debugging.`);
             return;
         }
 
-        const debugConfig = lldbId === debugEngine.id
-            ? getLldbDebugConfig(config, ctx.config.debug.sourceFileMap)
-            : await getCppvsDebugConfig(config, ctx.config.debug.sourceFileMap);
+        debugOutput.clear();
+        if (ctx.config.debug.openUpDebugPane) {
+            debugOutput.show(true);
+        }
+
+        const executable = await getDebugExecutable(config);
+        const debugConfig = knownEngines[debugEngine.id](config, executable, debugOptions.sourceFileMap);
+        if (debugConfig.type in debugOptions.engineSettings) {
+            const settingsMap = (debugOptions.engineSettings as any)[debugConfig.type];
+            for (var key in settingsMap) {
+                debugConfig[key] = settingsMap[key];
+            }
+        }
 
+        debugOutput.appendLine("Launching debug configuration:");
+        debugOutput.appendLine(JSON.stringify(debugConfig, null, 2));
         return vscode.debug.startDebugging(undefined, debugConfig);
     };
 }
diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index 46de922f3..be2e27aec 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -109,10 +109,14 @@ export class Config {
     }
 
     get debug() {
+        // "/rustc/<id>" used by suggestions only.
+        const { ["/rustc/<id>"]: _, ...sourceFileMap } = this.get<Record<string, string>>("debug.sourceFileMap");
+
         return {
             engine: this.get<string>("debug.engine"),
-            sourceFileMap: this.get<Record<string, string>>("debug.sourceFileMap"),
+            engineSettings: this.get<object>("debug.engineSettings"),
+            openUpDebugPane: this.get<boolean>("debug.openUpDebugPane"),
+            sourceFileMap: sourceFileMap,
         };
     }
-
 }