src/goDebugConfiguration: enable dlv-dap for local debugging

And, mark dlv-dap as an important tool (we will need it instead of dlv)

Updates #1657

Change-Id: Id0a9b9c287c64958871ac81b42c80b8844dcfab7
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/339094
Trust: Hyang-Ah Hana Kim <hyangah@gmail.com>
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Suzy Mueller <suzmue@golang.org>

Author: hyangah

src/goDebugConfiguration.ts

@@ -18,12 +18,11 @@ import {
 	promptForUpdatingTool,
 	shouldUpdateTool
 } from './goInstallTools';
-import { isInPreviewMode } from './goLanguageServer';
 import { packagePathToGoModPathMap } from './goModules';
 import { getTool, getToolAtVersion } from './goTools';
 import { pickProcess, pickProcessByName } from './pickProcess';
 import { getFromGlobalState, updateGlobalState } from './stateUtils';
-import { getBinPath, getGoVersion, getWorkspaceFolderPath, resolvePath } from './util';
+import { getBinPath, getGoVersion } from './util';
 import { parseEnvFiles } from './utils/envUtils';
 import { resolveHomeDir } from './utils/pathUtils';
 
@@ -155,10 +154,8 @@ export class GoDebugConfigurationProvider implements vscode.DebugConfigurationPr
 			}
 		}
 		if (!debugConfiguration['debugAdapter']) {
-			// for nightly/dev mode, default to dlv-dap.
-			// TODO(hyangah): when we switch the stable version's default to 'dlv-dap', adjust this.
-			debugConfiguration['debugAdapter'] =
-				isInPreviewMode() && debugConfiguration['mode'] !== 'remote' ? 'dlv-dap' : 'legacy';
+			// for local mode, default to dlv-dap.
+			debugConfiguration['debugAdapter'] = debugConfiguration['mode'] !== 'remote' ? 'dlv-dap' : 'legacy';
 		}
 		if (debugConfiguration['debugAdapter'] === 'dlv-dap' && debugConfiguration['mode'] === 'remote') {
 			this.showWarning(

src/goToolsInformation.ts

@@ -220,7 +220,7 @@ export const allToolsInformation: { [key: string]: Tool } = {
 		importPath: 'github.com/go-delve/delve/cmd/dlv',
 		modulePath: 'github.com/go-delve/delve',
 		replacedByGopls: false,
-		isImportant: false,
+		isImportant: true,
 		description: 'Go debugger (Delve built for DAP experiment)',
 		defaultVersion: 'master', // Always build from the master.
 		minimumGoVersion: semver.coerce('1.14'), // last 3 versions per delve policy

test/integration/goDebugConfiguration.test.ts

@@ -575,7 +575,7 @@ suite('Debug Configuration Auto Mode', () => {
 
 suite('Debug Configuration Default DebugAdapter', () => {
 	const debugConfigProvider = new GoDebugConfigurationProvider();
-	test(`default debugAdapter when isInPreviewMode=${isInPreviewMode()} should be 'dlv-dap'`, () => {
+	test("default debugAdapter should be 'dlv-dap'", () => {
 		const config = {
 			name: 'Launch',
 			type: 'go',
@@ -586,8 +586,7 @@ suite('Debug Configuration Default DebugAdapter', () => {
 
 		debugConfigProvider.resolveDebugConfiguration(undefined, config);
 		const resolvedConfig = config as any;
-		const want = isInPreviewMode() ? 'dlv-dap' : 'legacy';
-		assert.strictEqual(resolvedConfig['debugAdapter'], want);
+		assert.strictEqual(resolvedConfig['debugAdapter'], 'dlv-dap');
 	});
 
 	test("default debugAdapter for remote mode should be always 'legacy'", () => {