src/goTest: Add command Test Function At Cursor or Test Previous

This runs `Test Function At Cursor` if a unit test is found at the
cursor, otherwise it turns `Test Previous`.

Fixes #1508

Change-Id: I91305797dfeccd79c1f5ea14298a60803f24492b
GitHub-Last-Rev: 0054155
GitHub-Pull-Request: #1509
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/320769
Trust: Michael Knyszek <mknyszek@google.com>
Trust: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>

Author: mislav

Diff for: docs/commands.md

@@ -35,6 +35,10 @@ List all the Go tools being used by this extension along with their locations.
 
 Runs a unit test at the cursor.
 
+### `Go: Test Function At Cursor or Test Previous`
+
+Runs a unit test at the cursor if one is found, otherwise re-runs the last executed test.
+
 ### `Go: Subtest At Cursor`
 
 Runs a sub test at the cursor.

Diff for: package.json

@@ -201,6 +201,11 @@
         "title": "Go: Test Function At Cursor",
         "description": "Runs a unit test at the cursor."
       },
+      {
+        "command": "go.test.cursorOrPrevious",
+        "title": "Go: Test Function At Cursor or Test Previous",
+        "description": "Runs a unit test at the cursor if one is found, otherwise re-runs the last executed test."
+      },
       {
         "command": "go.subtest.cursor",
         "title": "Go: Subtest At Cursor",

Diff for: src/goMain.ts

@@ -64,6 +64,7 @@ import {
 	debugPrevious,
 	subTestAtCursor,
 	testAtCursor,
+	testAtCursorOrPrevious,
 	testCurrentFile,
 	testCurrentPackage,
 	testPrevious,
@@ -316,6 +317,13 @@ If you would like additional configuration for diagnostics from gopls, please se
 		})
 	);
 
+	ctx.subscriptions.push(
+		vscode.commands.registerCommand('go.test.cursorOrPrevious', (args) => {
+			const goConfig = getGoConfig();
+			testAtCursorOrPrevious(goConfig, 'test', args);
+		})
+	);
+
 	ctx.subscriptions.push(
 		vscode.commands.registerCommand('go.subtest.cursor', (args) => {
 			const goConfig = getGoConfig();

Diff for: src/goTest.ts

@@ -31,50 +31,68 @@ let lastDebugWorkspaceFolder: vscode.WorkspaceFolder;
 
 export type TestAtCursorCmd = 'debug' | 'test' | 'benchmark';
 
-/**
- * Executes the unit test at the primary cursor using `go test`. Output
- * is sent to the 'Go' channel.
- * @param goConfig Configuration for the Go extension.
- * @param cmd Whether the command is test , benchmark or debug.
- * @param args
- */
-export function testAtCursor(goConfig: vscode.WorkspaceConfiguration, cmd: TestAtCursorCmd, args: any) {
+class NotFoundError extends Error {}
+
+async function _testAtCursor(goConfig: vscode.WorkspaceConfiguration, cmd: TestAtCursorCmd, args: any) {
 	const editor = vscode.window.activeTextEditor;
 	if (!editor) {
-		vscode.window.showInformationMessage('No editor is active.');
-		return;
+		throw new NotFoundError('No editor is active.');
 	}
 	if (!editor.document.fileName.endsWith('_test.go')) {
-		vscode.window.showInformationMessage('No tests found. Current file is not a test file.');
-		return;
+		throw new NotFoundError('No tests found. Current file is not a test file.');
 	}
 
 	const getFunctions = cmd === 'benchmark' ? getBenchmarkFunctions : getTestFunctions;
+	const testFunctions = await getFunctions(editor.document, null);
+	// We use functionName if it was provided as argument
+	// Otherwise find any test function containing the cursor.
+	const testFunctionName =
+		args && args.functionName
+			? args.functionName
+			: testFunctions.filter((func) => func.range.contains(editor.selection.start)).map((el) => el.name)[0];
+	if (!testFunctionName) {
+		throw new NotFoundError('No test function found at cursor.');
+	}
 
-	editor.document.save().then(async () => {
-		try {
-			const testFunctions = await getFunctions(editor.document, null);
-			// We use functionName if it was provided as argument
-			// Otherwise find any test function containing the cursor.
-			const testFunctionName =
-				args && args.functionName
-					? args.functionName
-					: testFunctions
-							.filter((func) => func.range.contains(editor.selection.start))
-							.map((el) => el.name)[0];
-			if (!testFunctionName) {
-				vscode.window.showInformationMessage('No test function found at cursor.');
-				return;
-			}
+	await editor.document.save();
 
-			if (cmd === 'debug') {
-				await debugTestAtCursor(editor, testFunctionName, testFunctions, goConfig);
-			} else if (cmd === 'benchmark' || cmd === 'test') {
-				await runTestAtCursor(editor, testFunctionName, testFunctions, goConfig, cmd, args);
-			} else {
-				throw new Error('Unsupported command.');
-			}
-		} catch (err) {
+	if (cmd === 'debug') {
+		return debugTestAtCursor(editor, testFunctionName, testFunctions, goConfig);
+	} else if (cmd === 'benchmark' || cmd === 'test') {
+		return runTestAtCursor(editor, testFunctionName, testFunctions, goConfig, cmd, args);
+	} else {
+		throw new Error(`Unsupported command: ${cmd}`);
+	}
+}
+
+/**
+ * Executes the unit test at the primary cursor using `go test`. Output
+ * is sent to the 'Go' channel.
+ * @param goConfig Configuration for the Go extension.
+ * @param cmd Whether the command is test, benchmark, or debug.
+ * @param args
+ */
+export function testAtCursor(goConfig: vscode.WorkspaceConfiguration, cmd: TestAtCursorCmd, args: any) {
+	_testAtCursor(goConfig, cmd, args).catch((err) => {
+		if (err instanceof NotFoundError) {
+			vscode.window.showInformationMessage(err.message);
+		} else {
+			console.error(err);
+		}
+	});
+}
+
+/**
+ * Executes the unit test at the primary cursor if found, otherwise re-runs the previous test.
+ * @param goConfig Configuration for the Go extension.
+ * @param cmd Whether the command is test, benchmark, or debug.
+ * @param args
+ */
+export function testAtCursorOrPrevious(goConfig: vscode.WorkspaceConfiguration, cmd: TestAtCursorCmd, args: any) {
+	_testAtCursor(goConfig, cmd, args).catch((err) => {
+		if (err instanceof NotFoundError) {
+			testPrevious();
+		} else {
 			console.error(err);
 		}
 	});