Improve failFast at API level

Don't run new test files after:

* A timeout has occurred
* A test has failed
* Running the test file itself caused an error

Refs #1158.

Author: novemberborn

api.js

@@ -56,11 +56,20 @@ class Api extends EventEmitter {
 		};
 
 		// Track active forks and manage timeouts.
+		const failFast = apiOptions.failFast === true;
+		let bailed = false;
 		const pendingForks = new Set();
 		let restartTimer;
 		if (apiOptions.timeout) {
 			const timeout = ms(apiOptions.timeout);
+
 			restartTimer = debounce(() => {
+				// If failFast is active, prevent new test files from running after
+				// the current ones are exited.
+				if (failFast) {
+					bailed = true;
+				}
+
 				for (const fork of pendingForks) {
 					fork.exit();
 				}
@@ -78,11 +87,20 @@ class Api extends EventEmitter {
 					runOnlyExclusive: runtimeOptions.runOnlyExclusive,
 					prefixTitles: apiOptions.explicitTitles || files.length > 1,
 					base: path.relative(process.cwd(), commonPathPrefix(files)) + path.sep,
-					failFast: apiOptions.failFast,
+					failFast,
 					updateSnapshots: runtimeOptions.updateSnapshots
 				});
 
 				runStatus.on('test', restartTimer);
+				if (failFast) {
+					// Prevent new test files from running once a test has failed.
+					runStatus.on('test', test => {
+						if (test.error) {
+							bailed = true;
+						}
+					});
+				}
+
 				this.emit('test-run', runStatus, files);
 
 				// Bail out early if no files were found.
@@ -130,6 +148,12 @@ class Api extends EventEmitter {
 
 						// Try and run each file, limited by `concurrency`.
 						return Bluebird.map(files, file => {
+							// No new files should be run once a test has timed out or failed,
+							// and failFast is enabled.
+							if (bailed) {
+								return null;
+							}
+
 							let forked;
 							return Bluebird.resolve(
 								this._computeForkExecArgv().then(execArgv => {
@@ -157,6 +181,10 @@ class Api extends EventEmitter {
 
 									return forked;
 								}).catch(err => {
+									// Prevent new test files from running.
+									if (failFast) {
+										bailed = true;
+									}
 									handleError(Object.assign(err, {file}));
 									return null;
 								})

test/api.js

@@ -202,7 +202,7 @@ test('display filename prefixes for failed test stack traces in subdirs', t => {
 		});
 });
 
-test('fail-fast mode', t => {
+test('fail-fast mode - single file', t => {
 	const api = apiCreator({
 		failFast: true
 	});
@@ -218,7 +218,7 @@ test('fail-fast mode', t => {
 		});
 	});
 
-	return api.run([path.join(__dirname, 'fixture/fail-fast.js')])
+	return api.run([path.join(__dirname, 'fixture/fail-fast/single-file/test.js')])
 		.then(result => {
 			t.ok(api.options.failFast);
 			t.strictDeepEqual(tests, [{
@@ -233,6 +233,121 @@ test('fail-fast mode', t => {
 		});
 });
 
+test('fail-fast mode - multiple files', t => {
+	const api = apiCreator({
+		failFast: true,
+		serial: true
+	});
+
+	const tests = [];
+
+	api.on('test-run', runStatus => {
+		runStatus.on('test', test => {
+			tests.push({
+				ok: !test.error,
+				title: test.title
+			});
+		});
+	});
+
+	return api.run([
+		path.join(__dirname, 'fixture/fail-fast/multiple-files/fails.js'),
+		path.join(__dirname, 'fixture/fail-fast/multiple-files/passes.js')
+	])
+		.then(result => {
+			t.ok(api.options.failFast);
+			t.strictDeepEqual(tests, [{
+				ok: true,
+				title: 'fails › first pass'
+			}, {
+				ok: false,
+				title: 'fails › second fail'
+			}]);
+			t.is(result.passCount, 1);
+			t.is(result.failCount, 1);
+		});
+});
+
+test('fail-fast mode - crash', t => {
+	const api = apiCreator({
+		failFast: true,
+		serial: true
+	});
+
+	const tests = [];
+	const errors = [];
+
+	api.on('test-run', runStatus => {
+		runStatus.on('test', test => {
+			tests.push({
+				ok: !test.error,
+				title: test.title
+			});
+		});
+		runStatus.on('error', err => {
+			errors.push(err);
+		});
+	});
+
+	return api.run([
+		path.join(__dirname, 'fixture/fail-fast/crash/crashes.js'),
+		path.join(__dirname, 'fixture/fail-fast/crash/passes.js')
+	])
+		.then(result => {
+			t.ok(api.options.failFast);
+			t.strictDeepEqual(tests, []);
+			t.is(errors.length, 1);
+			t.is(errors[0].name, 'AvaError');
+			t.is(errors[0].message, 'test/fixture/fail-fast/crash/crashes.js exited with a non-zero exit code: 1');
+			t.is(result.passCount, 0);
+			t.is(result.failCount, 0);
+		});
+});
+
+test('fail-fast mode - timeout', t => {
+	const api = apiCreator({
+		failFast: true,
+		serial: true,
+		timeout: '100ms'
+	});
+
+	const tests = [];
+	const errors = [];
+
+	api.on('test-run', runStatus => {
+		runStatus.on('test', test => {
+			tests.push({
+				ok: !test.error,
+				title: test.title
+			});
+		});
+		runStatus.on('error', err => {
+			errors.push(err);
+		});
+	});
+
+	return api.run([
+		path.join(__dirname, 'fixture/fail-fast/timeout/fails.js'),
+		path.join(__dirname, 'fixture/fail-fast/timeout/passes.js')
+	])
+		.then(result => {
+			t.ok(api.options.failFast);
+			if (tests.length > 0) {
+				t.is(tests.length, 1);
+				// FIXME: The fails.js test file should have exited without the pending
+				// test completing, but that's not always the case.
+				t.is(tests[0].title, 'fails › slow pass');
+				t.is(result.passCount, 1);
+			} else {
+				t.is(result.passCount, 0);
+			}
+			t.is(errors.length, 1);
+			t.is(errors[0].name, 'AvaError');
+			t.is(errors[0].message, 'Exited because no new tests completed within the last 100ms of inactivity');
+			t.is(result.failCount, 0);
+		});
+});
+
 test('serial execution mode', t => {
 	const api = apiCreator({
 		serial: true

test/fixture/fail-fast/crash/crashes.js

@@ -0,0 +1,3 @@
+import '../../../../'; // eslint-disable-line import/no-unassigned-import
+
+process.exit(1); // eslint-disable-line unicorn/no-process-exit

test/fixture/fail-fast/crash/passes.js

@@ -0,0 +1,5 @@
+import test from '../../../../';
+
+test('first pass', t => {
+	t.pass();
+});

test/fixture/fail-fast.js renamed to test/fixture/fail-fast/multiple-files/fails.js

@@ -1,4 +1,4 @@
-import test from '../../';
+import test from '../../../../';
 
 test('first pass', t => {
 	t.pass();

test/fixture/fail-fast/multiple-files/passes.js

@@ -0,0 +1,5 @@
+import test from '../../../../';
+
+test('first pass', t => {
+	t.pass();
+});

test/fixture/fail-fast/single-file/test.js

@@ -0,0 +1,13 @@
+import test from '../../../../';
+
+test('first pass', t => {
+	t.pass();
+});
+
+test('second fail', t => {
+	t.fail();
+});
+
+test('third pass', t => {
+	t.pass();
+});

test/fixture/fail-fast/timeout/fails.js

@@ -0,0 +1,5 @@
+import test from '../../../../';
+
+test.cb('slow pass', t => {
+	setTimeout(t.end, 1000);
+});

test/fixture/fail-fast/timeout/passes.js

@@ -0,0 +1,5 @@
+import test from '../../../../';
+
+test('first pass', t => {
+	t.pass();
+});