1 files changed, 124 insertions, 0 deletions

diff --git a/editors/code/src/debug.ts b/editors/code/src/debug.ts
new file mode 100644
index 000000000..d3fe588e8
--- /dev/null
+++ b/editors/code/src/debug.ts
@@ -0,0 +1,124 @@
+import * as os from "os";
+import * as vscode from 'vscode';
+import * as path from 'path';
+import * as ra from './rust-analyzer-api';
+
+import { Cargo } from './cargo';
+import { Ctx } from "./ctx";
+
+const debugOutput = vscode.window.createOutputChannel("Debug");
+type DebugConfigProvider = (config: ra.Runnable, executable: string, 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,
+        program: executable,
+        args: config.extraArgs,
+        cwd: config.cwd,
+        sourceMap: sourceFileMap,
+        sourceLanguages: ["rust"]
+    };
+}
+
+function getCppvsDebugConfig(config: ra.Runnable, executable: string, sourceFileMap?: Record<string, string>): vscode.DebugConfiguration {
+    return {
+        type: (os.platform() === "win32") ? "cppvsdbg" : "cppdbg",
+        request: "launch",
+        name: config.label,
+        program: executable,
+        args: config.extraArgs,
+        cwd: config.cwd,
+        sourceFileMap: sourceFileMap,
+    };
+}
+
+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;
+}
+
+export async function getDebugConfiguration(ctx: Ctx, config: ra.Runnable): Promise<vscode.DebugConfiguration | undefined> {
+    const editor = ctx.activeRustEditor;
+    if (!editor) return;
+
+    const knownEngines: Record<string, DebugConfigProvider> = {
+        "vadimcn.vscode-lldb": getLldbDebugConfig,
+        "ms-vscode.cpptools": getCppvsDebugConfig
+    };
+    const debugOptions = ctx.config.debug;
+
+    let debugEngine = null;
+    if (debugOptions.engine === "auto") {
+        for (var engineId in knownEngines) {
+            debugEngine = vscode.extensions.getExtension(engineId);
+            if (debugEngine) break;
+        }
+    } else {
+        debugEngine = vscode.extensions.getExtension(debugOptions.engine);
+    }
+
+    if (!debugEngine) {
+        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;
+    }
+
+    debugOutput.clear();
+    if (ctx.config.debug.openUpDebugPane) {
+        debugOutput.show(true);
+    }
+
+    const wsFolder = path.normalize(vscode.workspace.workspaceFolders![0].uri.fsPath); // folder exists or RA is not active.
+    function simplifyPath(p: string): string {
+        return path.normalize(p).replace(wsFolder, '${workspaceRoot}');
+    }
+
+    const executable = await getDebugExecutable(config);
+    const debugConfig = knownEngines[debugEngine.id](config, simplifyPath(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];
+        }
+    }
+
+    if (debugConfig.name === "run binary") {
+        // The LSP side: crates\rust-analyzer\src\main_loop\handlers.rs,
+        // fn to_lsp_runnable(...) with RunnableKind::Bin
+        debugConfig.name = `run ${path.basename(executable)}`;
+    }
+
+    if (debugConfig.cwd) {
+        debugConfig.cwd = simplifyPath(debugConfig.cwd);
+    }
+
+    return debugConfig;
+}
+
+export async function startDebugSession(ctx: Ctx, config: ra.Runnable): Promise<boolean> {
+    let debugConfig: vscode.DebugConfiguration | undefined = undefined;
+    let message = "";
+
+    const wsLaunchSection = vscode.workspace.getConfiguration("launch");
+    const configurations = wsLaunchSection.get<any[]>("configurations") || [];
+
+    const index = configurations.findIndex(c => c.name === config.label);
+    if (-1 !== index) {
+        debugConfig = configurations[index];
+        message = " (from launch.json)";
+        debugOutput.clear();
+    } else {
+        debugConfig = await getDebugConfiguration(ctx, config);
+    }
+
+    if (!debugConfig) return false;
+
+    debugOutput.appendLine(`Launching debug configuration${message}:`);
+    debugOutput.appendLine(JSON.stringify(debugConfig, null, 2));
+    return vscode.debug.startDebugging(undefined, debugConfig);
+}