Add support for gotests

Implements three new commands that use gotests:
- go.test.generate.package: generates all unit-test squeletons for
  the current package.
- go.test.generate.file: generates all unit-test squeletons for
  the current file.
- go.test.generate.function: generates unit-test squeleton for the
  selected function in the current file.

.travis.yml

@@ -31,6 +31,7 @@ install:
   - go get -u -v github.com/newhook/go-symbols
   - go get -u -v golang.org/x/tools/cmd/guru
   - go get -u -v github.com/alecthomas/gometalinter
+  - go get -u -v github.com/cweill/gotests
   - GO15VENDOREXPERIMENT=1 gometalinter --install
 
 script:

README.md

@@ -19,6 +19,7 @@ This extension adds rich language support for the Go language to VS Code, includ
 - Build-on-save (using `go build` and `go test`)
 - Lint-on-save (using `golint` or `gometalinter`)
 - Format (using `goreturns` or `goimports` or `gofmt`)
+- Generate unit tests squeleton (using `gotests`)
 - Add Imports (using `gopkgs`)
 - [_partially implemented_] Debugging (using `delve`)
 
@@ -98,6 +99,9 @@ In addition to integrated editing features, the extension also provides several
 * `Go: Run test at cursor` to run a test at the current cursor position in the active document
 * `Go: Run tests in current package` to run all tests in the package containing the active document
 * `Go: Run tests in current file` to run all tests in the current active document
+* `Go: Generates unit tests (package)` Generates unit tests for the current package
+* `Go: Generates unit tests (file)` Generates unit tests for the current file
+* `Go: Generates unit tests (function)` Generates unit tests for the selected function in the current file
 
 ### _Optional_: Debugging
 
@@ -200,6 +204,7 @@ The extension uses the following tools, installed in the current GOPATH.  If any
 - gopkgs: `go get -u -v github.com/tpng/gopkgs`
 - go-symbols: `go get -u -v github.com/newhook/go-symbols`
 - guru: `go get -u -v golang.org/x/tools/cmd/guru`
+- gotests: `go get -u -v github.com/cweill/gotests`
 
 To install them just paste and run:
 ```bash
@@ -212,6 +217,7 @@ go get -u -v golang.org/x/tools/cmd/gorename
 go get -u -v github.com/tpng/gopkgs
 go get -u -v github.com/newhook/go-symbols
 go get -u -v golang.org/x/tools/cmd/guru
+go get -u -v github.com/cweill/gotests
 ```
 
 And for debugging:

package.json

@@ -101,6 +101,21 @@
         "title": "Go: Test coverage in current package",
         "description": "Displays test coverage in the current package."
       },
+      {
+        "command": "go.test.generate.package",
+        "title": "Go: Generates unit tests (package)",
+        "description": "Generates unit tests for the current package"
+      },
+      {
+        "command": "go.test.generate.file",
+        "title": "Go: Generates unit tests (file)",
+        "description": "Generates unit tests for the current file"
+      },
+       {
+        "command": "go.test.generate.function",
+        "title": "Go: Generates unit tests (function)",
+        "description": "Generates unit tests for the selected function in the current file"
+      },
       {
         "command": "go.import.add",
         "title": "Go: Add Import",

src/goInstallTools.ts

@@ -24,7 +24,8 @@ let tools: { [key: string]: string } = {
 	'go-symbols': 'github.com/newhook/go-symbols',
 	'guru': 'golang.org/x/tools/cmd/guru',
 	'gorename': 'golang.org/x/tools/cmd/gorename',
-	'goimports': 'golang.org/x/tools/cmd/goimports'
+	'goimports': 'golang.org/x/tools/cmd/goimports',
+	'gotests': 'github.com/cweill/gotests'
 };
 
 export function installAllTools() {

src/goMain.ts

@@ -24,6 +24,7 @@ import { updateGoPathGoRootFromConfig, setupGoPathAndOfferToInstallTools } from
 import { GO_MODE } from './goMode';
 import { showHideStatus } from './goStatus';
 import { coverageCurrentPackage, getCodeCoverage, removeCodeCoverage } from './goCover';
+import { generateTestCurrentPackage, generateTestCurrentFile, generateTestCurrentFunction } from './goTests';
 import { testAtCursor, testCurrentPackage, testCurrentFile } from './goTest';
 import { addImport } from './goImport';
 import { installAllTools } from './goInstallTools';
@@ -88,6 +89,18 @@ export function activate(ctx: vscode.ExtensionContext): void {
 		updateGoPathGoRootFromConfig();
 	}));
 
+	ctx.subscriptions.push(vscode.commands.registerCommand('go.test.generate.package', () => {
+		generateTestCurrentPackage();
+	}));
+
+	ctx.subscriptions.push(vscode.commands.registerCommand('go.test.generate.file', () => {
+		generateTestCurrentFile();
+	}));
+
+	ctx.subscriptions.push(vscode.commands.registerCommand('go.test.generate.function', () => {
+		generateTestCurrentFunction();
+	}));
+
 	vscode.languages.setLanguageConfiguration(GO_MODE.language, {
 		indentationRules: {
 			// ^(.*\*/)?\s*\}.*$

src/goTests.ts

@@ -0,0 +1,113 @@
+/*---------------------------------------------------------
+ * Copyright (C) Microsoft Corporation. All rights reserved.
+ * Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------*/
+
+'use strict';
+
+import cp = require('child_process');
+import path = require('path');
+import vscode = require('vscode');
+import util = require('util');
+
+import { getBinPath } from './goPath';
+import { promptForMissingTool } from './goInstallTools';
+import { GoDocumentSymbolProvider } from './goOutline';
+
+export function generateTestCurrentPackage() {
+	let editor = testEditor();
+	let dir = path.dirname(editor.document.uri.fsPath);
+	generateTests({dir: dir});
+	vscode.window.showInformationMessage('gotests: Unit tests generated for package:' + path.basename(dir));
+}
+
+export function generateTestCurrentFile() {
+	let editor = testEditor();
+	let file = editor.document.uri.fsPath;
+	generateTests({dir: file});
+	vscode.window.showInformationMessage('gotests: Unit tests generated for file:' + path.basename(file));
+}
+
+export function generateTestCurrentFunction() {
+	let editor = testEditor();
+	let file = editor.document.uri.fsPath;
+
+	getFunctions(editor.document).then(functions => {
+		let currentFunction: vscode.SymbolInformation;
+		for (let func of functions) {
+			let selection = editor.selection;
+			if (selection && func.location.range.contains(selection.start)) {
+				currentFunction = func;
+				break;
+			}
+		};
+		if (!currentFunction) {
+			vscode.window.setStatusBarMessage('No function found at cursor.', 5000);
+			return;
+		}
+		generateTests({dir: file, func: currentFunction.name});
+		vscode.window.showInformationMessage('gotests: Unit test generated for function: ' + currentFunction.name + ' in file:' + path.basename(file));
+	}).then(null, err => {
+		console.error(err);
+	});
+}
+
+/**
+ * Input to goTests.
+ */
+interface Config {
+	/**
+	 * The working directory for `gotests`.
+	 */
+	dir: string;
+	/**
+	 * Specific function names to generate tests squeleton.
+	 */
+	func?: string;
+}
+
+function generateTests(conf: Config): Thenable<vscode.WorkspaceEdit> {
+	return new Promise<vscode.WorkspaceEdit>((resolve, reject) => {
+		let cmd = getBinPath('gotests');
+		let args;
+		if (conf.func) {
+			args = ['-w', '-only', conf.func, conf.dir];
+		} else {
+			args = ['-w', '-all', conf.dir];
+		}
+		cp.execFile(cmd, args, {}, (err, stdout, stderr) => {
+			try {
+				if (err && (<any>err).code === 'ENOENT') {
+					promptForMissingTool('gotests');
+					return resolve(null);
+				}
+				if (err) {
+					return reject('Cannot generate test due to errors: ' + stderr);
+				}
+				return resolve(new vscode.WorkspaceEdit());
+			} catch (e) {
+				vscode.window.showInformationMessage(e.msg);
+				reject(e);
+			}
+		});
+	});
+}
+
+function testEditor(): vscode.TextEditor {
+	let editor = vscode.window.activeTextEditor;
+	if (!editor) {
+		vscode.window.showInformationMessage('No editor is active.');
+		return;
+	}
+	return editor;
+}
+
+function getFunctions(doc: vscode.TextDocument): Thenable<vscode.SymbolInformation[]> {
+	let documentSymbolProvider = new GoDocumentSymbolProvider();
+	return documentSymbolProvider
+		.provideDocumentSymbols(doc, null)
+		.then(symbols =>
+			symbols.filter(sym =>
+				sym.kind === vscode.SymbolKind.Function)
+		);
+}