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src/vs/vscode.proposed.d.ts

@@ -365,13 +365,13 @@ declare module 'vscode' {
 	export class DebugAdapterExecutable {
 		/**
 		 * The command path of the debug adapter executable.
-		 * A command must be a either an absolute path or a name of an executable looked up via the PATH environment variable.
+		 * A command must be either an absolute path or the name of an executable looked up via the PATH environment variable.
 		 * The special value 'node' will be mapped to VS Code's built-in node runtime.
 		 */
 		readonly command: string;
 
 		/**
-		 * Optional arguments passed to the debug adapter.
+		 * Optional arguments passed to the debug adapter executable.
 		 */
 		readonly args: string[];
 

src/vs/workbench/parts/debug/common/debug.ts

@@ -431,7 +431,7 @@ export interface IConfigurationManager {
 	unregisterDebugConfigurationProvider(handle: number): void;
 
 	resolveConfigurationByProviders(folderUri: uri | undefined, type: string | undefined, debugConfiguration: any): TPromise<any>;
-	debugAdapterExecutable(folderUri: uri | undefined, type: string): TPromise<IAdapterExecutable> | undefined;
+	debugAdapterExecutable(folderUri: uri | undefined, type: string): TPromise<IAdapterExecutable | undefined>;
 }
 
 export interface ILaunch {

src/vs/workbench/parts/debug/electron-browser/debugConfigurationManager.ts

@@ -291,12 +291,12 @@ export class ConfigurationManager implements IConfigurationManager {
 			.then(results => results.reduce((first, second) => first.concat(second), []));
 	}
 
-	public debugAdapterExecutable(folderUri: uri | undefined, type: string): TPromise<IAdapterExecutable> | undefined {
+	public debugAdapterExecutable(folderUri: uri | undefined, type: string): TPromise<IAdapterExecutable | undefined> {
 		const providers = this.providers.filter(p => p.type === type && p.debugAdapterExecutable);
 		if (providers.length === 1) {
 			return providers[0].debugAdapterExecutable(folderUri);
 		}
-		return undefined;
+		return TPromise.as(undefined);
 	}
 
 	private registerListeners(lifecycleService: ILifecycleService): void {

src/vs/workbench/parts/debug/node/debugAdapter.ts

@@ -33,35 +33,32 @@ export class Adapter {
 
 	public getAdapterExecutable(root: IWorkspaceFolder, verifyAgainstFS = true): TPromise<IAdapterExecutable> {
 
-		// start with extension API
-		if (this.configurationManager) {
-			const adapterExecutablePromise = this.configurationManager.debugAdapterExecutable(root.uri, this.rawAdapter.type);
-			if (adapterExecutablePromise) {
-				return adapterExecutablePromise.then(adapterExecutable => {
-					return this.verifyAdapterDetails(adapterExecutable, verifyAgainstFS);
-				});
+		return this.configurationManager.debugAdapterExecutable(root ? root.uri : undefined, this.rawAdapter.type).then(adapterExecutable => {
+
+			if (adapterExecutable) {
+				return this.verifyAdapterDetails(adapterExecutable, verifyAgainstFS);
 			}
-		}
 
-		// try deprecated command based extension API
-		if (this.rawAdapter.adapterExecutableCommand && root) {
-			return this.commandService.executeCommand<IAdapterExecutable>(this.rawAdapter.adapterExecutableCommand, root.uri.toString()).then(ad => {
-				return this.verifyAdapterDetails(ad, verifyAgainstFS);
-			});
-		}
+			// try deprecated command based extension API
+			if (this.rawAdapter.adapterExecutableCommand && root) {
+				return this.commandService.executeCommand<IAdapterExecutable>(this.rawAdapter.adapterExecutableCommand, root.uri.toString()).then(ad => {
+					return this.verifyAdapterDetails(ad, verifyAgainstFS);
+				});
+			}
 
-		// old style: executable contribution specified in package.json
-		const adapterExecutable = <IAdapterExecutable>{
-			command: this.getProgram(),
-			args: this.getAttributeBasedOnPlatform('args')
-		};
-		const runtime = this.getRuntime();
-		if (runtime) {
-			const runtimeArgs = this.getAttributeBasedOnPlatform('runtimeArgs');
-			adapterExecutable.args = (runtimeArgs || []).concat([adapterExecutable.command]).concat(adapterExecutable.args || []);
-			adapterExecutable.command = runtime;
-		}
-		return this.verifyAdapterDetails(adapterExecutable, verifyAgainstFS);
+			// fallback: executable contribution specified in package.json
+			adapterExecutable = <IAdapterExecutable>{
+				command: this.getProgram(),
+				args: this.getAttributeBasedOnPlatform('args')
+			};
+			const runtime = this.getRuntime();
+			if (runtime) {
+				const runtimeArgs = this.getAttributeBasedOnPlatform('runtimeArgs');
+				adapterExecutable.args = (runtimeArgs || []).concat([adapterExecutable.command]).concat(adapterExecutable.args || []);
+				adapterExecutable.command = runtime;
+			}
+			return this.verifyAdapterDetails(adapterExecutable, verifyAgainstFS);
+		});
 	}
 
 	private verifyAdapterDetails(details: IAdapterExecutable, verifyAgainstFS: boolean): TPromise<IAdapterExecutable> {

src/vs/workbench/parts/debug/test/node/debugAdapter.test.ts

@@ -6,9 +6,12 @@
 import * as assert from 'assert';
 import * as paths from 'vs/base/common/paths';
 import * as platform from 'vs/base/common/platform';
-import { IRawAdapter } from 'vs/workbench/parts/debug/common/debug';
+import { IRawAdapter, IAdapterExecutable, IConfigurationManager } from 'vs/workbench/parts/debug/common/debug';
 import { Adapter } from 'vs/workbench/parts/debug/node/debugAdapter';
 import { TestConfigurationService } from 'vs/platform/configuration/test/common/testConfigurationService';
+import uri from 'vs/base/common/uri';
+import { TPromise } from 'vs/base/common/winjs.base';
+
 
 suite('Debug - Adapter', () => {
 	let adapter: Adapter;
@@ -41,9 +44,14 @@ suite('Debug - Adapter', () => {
 			}
 		]
 	};
+	const configurationManager = {
+		debugAdapterExecutable(folderUri: uri | undefined, type: string): TPromise<IAdapterExecutable | undefined> {
+			return TPromise.as(undefined);
+		}
+	};
 
 	setup(() => {
-		adapter = new Adapter(null, rawAdapter, { extensionFolderPath, id: 'adapter', name: 'myAdapter', version: '1.0.0', publisher: 'vscode', isBuiltin: false, engines: null },
+		adapter = new Adapter(<IConfigurationManager>configurationManager, rawAdapter, { extensionFolderPath, id: 'adapter', name: 'myAdapter', version: '1.0.0', publisher: 'vscode', isBuiltin: false, engines: null },
 			new TestConfigurationService(), null);
 	});