src/debugAdapter2: launch as an external process, and fix config

Eventually we want to inline the debug adapter, but until it gets
more stable and becomes the default adapter, let's launch it
as a separate process to isolate failures. This is handled by the
definition in package.json.

In order to avoid accidental installation of the process-wide
uncaughtException handler when we switch back to the inline mode,
move the handler out of goDlvDebug.ts.

Also, fixes the default configuration provider for delve dap
debug adapter. It should use 'godlvdap' as the type.

Fixes #469
Updates #23

Change-Id: I4df2fff51c703995fd557fe5595a367d7048bd7b
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/246777
Reviewed-by: Polina Sokolova <polina@google.com>

src/debugAdapter2/goDlvDebug.ts

@@ -102,12 +102,6 @@ interface AttachRequestArguments extends DebugProtocol.AttachRequestArguments {
 	showGlobalVariables?: boolean;
 }
 
-process.on('uncaughtException', (err: any) => {
-	const errMessage = err && (err.stack || err.message);
-	logger.error(`Unhandled error in debug adapter: ${errMessage}`);
-	throw err;
-});
-
 function logArgsToString(args: any[]): string {
 	return args
 		.map((arg) => {

src/debugAdapter2/goDlvDebugMain.ts

@@ -5,6 +5,18 @@
 
 // This file is for running the godlvdap debug adapter as a standalone program
 // in a separate process (e.g. when working in --server mode).
+//
+// NOTE: we must not include this file when we switch to the inline debug adapter
+// launch mode. This installs a process-wide uncaughtException handler
+// which can result in the extension host crash.
+
+import { logger } from 'vscode-debugadapter';
 import { GoDlvDapDebugSession } from './goDlvDebug';
 
+process.on('uncaughtException', (err: any) => {
+	const errMessage = err && (err.stack || err.message);
+	logger.error(`Unhandled error in debug adapter: ${errMessage}`);
+	throw err;
+});
+
 GoDlvDapDebugSession.run(GoDlvDapDebugSession);

src/goDebugConfiguration.ts

@@ -14,14 +14,16 @@ import { getFromGlobalState, updateGlobalState } from './stateUtils';
 import { getBinPath, getCurrentGoPath, getGoConfig } from './util';
 
 export class GoDebugConfigurationProvider implements vscode.DebugConfigurationProvider {
+	constructor(private defaultDebugAdapterType: string = 'go') { }
+
 	public provideDebugConfigurations(
 		folder: vscode.WorkspaceFolder | undefined,
 		token?: vscode.CancellationToken
 	): vscode.DebugConfiguration[] {
 		return [
 			{
 				name: 'Launch',
-				type: 'go',
+				type: this.defaultDebugAdapterType,
 				request: 'launch',
 				mode: 'auto',
 				program: '${fileDirname}',
@@ -45,13 +47,17 @@ export class GoDebugConfigurationProvider implements vscode.DebugConfigurationPr
 
 			debugConfiguration = Object.assign(debugConfiguration || {}, {
 				name: 'Launch',
-				type: 'go',
+				type: this.defaultDebugAdapterType,
 				request: 'launch',
 				mode: 'auto',
 				program: path.dirname(activeEditor.document.fileName) // matches ${fileDirname}
 			});
 		}
 
+		if (!debugConfiguration.type) {
+			debugConfiguration['type'] = this.defaultDebugAdapterType;
+		}
+
 		debugConfiguration['packagePathToGoModPathMap'] = packagePathToGoModPathMap;
 
 		const gopath = getCurrentGoPath(folder ? folder.uri : undefined);

src/goMain.ts

@@ -118,17 +118,9 @@ export function activate(ctx: vscode.ExtensionContext) {
 
 	// debug
 	ctx.subscriptions.push(
-		vscode.debug.registerDebugConfigurationProvider('go', new GoDebugConfigurationProvider()));
+		vscode.debug.registerDebugConfigurationProvider('go', new GoDebugConfigurationProvider('go')));
 	ctx.subscriptions.push(
-		vscode.debug.registerDebugConfigurationProvider('godlvdap', new GoDebugConfigurationProvider()));
-
-	// Use an InlineDebugAdapterFactory to create a new debug adapter for
-	// the 'godlvdap' command in inline mode, without launching a subprocess.
-	const factory = new InlineDebugAdapterFactory();
-	ctx.subscriptions.push(vscode.debug.registerDebugAdapterDescriptorFactory('godlvdap', factory));
-	if ('dispose' in factory) {
-		ctx.subscriptions.push(factory);
-	}
+		vscode.debug.registerDebugConfigurationProvider('godlvdap', new GoDebugConfigurationProvider('godlvdap')));
 
 	buildDiagnosticCollection = vscode.languages.createDiagnosticCollection('go');
 	ctx.subscriptions.push(buildDiagnosticCollection);
@@ -562,13 +554,6 @@ function checkToolExists(tool: string) {
 	}
 }
 
-class InlineDebugAdapterFactory implements vscode.DebugAdapterDescriptorFactory {
-	public createDebugAdapterDescriptor(session: vscode.DebugSession
-	): vscode.ProviderResult<vscode.DebugAdapterDescriptor> {
-		return new vscode.DebugAdapterInlineImplementation(new GoDlvDapDebugSession());
-	}
-}
-
 async function suggestUpdates(ctx: vscode.ExtensionContext) {
 	const updateToolsCmdText = 'Update tools';
 	interface GoInfo {