go.gopath and go.toolsGopath now expand ${env:XXX} (#1743)

* go.gopath and go.toolsGopath now expand ${env:XXX}

* Fix linting errors

* remove 'm' flag from substituteEnv

* add test for substituteEnv

* add newline on end of utils.test.ts

src/util.ts

@@ -348,7 +348,7 @@ export function getToolsGopath(useCache: boolean = true): string {
 
 function resolveToolsGopath(): string {
 
-	let toolsGopathForWorkspace = vscode.workspace.getConfiguration('go')['toolsGopath'] || '';
+	let toolsGopathForWorkspace = substituteEnv(vscode.workspace.getConfiguration('go')['toolsGopath'] || '');
 
 	// In case of single root
 	if (!vscode.workspace.workspaceFolders || vscode.workspace.workspaceFolders.length <= 1) {
@@ -408,6 +408,12 @@ export function getToolsEnvVars(): any {
 	return envVars;
 }
 
+export function substituteEnv(input: string): string {
+	return input.replace(/\${env:([^}]+)}/g, function (match, capture) {
+		return process.env[capture.trim()] || '';
+	});
+}
+
 export function getCurrentGoPath(workspaceUri?: vscode.Uri): string {
 	let currentFilePath: string;
 	if (vscode.window.activeTextEditor && vscode.workspace.getWorkspaceFolder(vscode.window.activeTextEditor.document.uri)) {
@@ -443,7 +449,7 @@ export function getCurrentGoPath(workspaceUri?: vscode.Uri): string {
 		}
 	}
 
-	const configGopath = config['gopath'] ? resolvePath(config['gopath'], currentRoot) : '';
+	let configGopath = config['gopath'] ? resolvePath(substituteEnv(config['gopath']), currentRoot) : '';
 	return inferredGopath ? inferredGopath : (configGopath || process.env['GOPATH']);
 }
 

test/unit/utils.test.ts

@@ -0,0 +1,25 @@
+/*---------------------------------------------------------
+ * Copyright (C) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------*/
+
+import * as assert from 'assert';
+import { substituteEnv } from '../../src/util';
+
+suite('utils Tests', () => {
+	test('substituteEnv: default', () => {
+
+		// prepare test
+		const env = Object.assign({}, process.env);
+		process.env['test1'] = 'abcd';
+		process.env['test2'] = 'defg';
+
+		let actual = substituteEnv(' ${env:test1} \r\n ${env:test2}\r\n${env:test1}');
+		let expected = ' abcd \r\n defg\r\nabcd';
+
+		assert.equal(actual, expected);
+
+		// test completed
+		process.env = env;
+	});
+});