Support helper glob configuration

Fixes #2105.

docs/06-configuration.md

@@ -16,6 +16,9 @@ To ignore files, prefix the pattern with an `!` (exclamation mark).
 			"!test/exclude-files-in-this-directory/*",
 			"!**/exclude-files-with-this-name.*"
 		],
+		"helpers": [
+			"**/helpers/**/*"
+		],
 		"sources": [
 			"src/**/*",
 			"!dist/**/*"
@@ -49,6 +52,7 @@ Arguments passed to the CLI will always take precedence over the CLI options con
 ## Options
 
 - `files`: an array of glob patterns to select test files. Files with an underscore prefix are ignored. By default only selects files with `js` extensions, even if the pattern matches other files. Specify `extensions` and `babel.extensions` to allow other file extensions
+- `helpers`: an array of glob patterns to select helper files. Files matched here are never considered as tests. By default only selects files with `js` extensions, even if the pattern matches other files. Specify `extensions` and `babel.extensions` to allow other file extensions
 - `sources`: an array of glob patterns to match files that, when changed, cause tests to be re-run (when in watch mode). See the [watch mode recipe for details](https://github.com/avajs/ava/blob/master/docs/recipes/watch-mode.md#source-files-and-test-files)
 - `match`: not typically useful in the `package.json` configuration, but equivalent to [specifying `--match` on the CLI](./05-command-line.md#running-tests-with-matching-titles)
 - `cache`: cache compiled test and helper files under `node_modules/.cache/ava`. If `false`, files are cached in a temporary directory instead

lib/api.js

@@ -110,12 +110,17 @@ class Api extends Emittery {
 			const precompiler = await this._setupPrecompiler();
 			let helpers = [];
 			if (files.length === 0 || precompiler.enabled) {
-				const found = await globs.findHelpersAndTests({cwd: this.options.resolveTestsFrom, ...apiOptions.globs});
+				let found;
+				if (precompiler.enabled) {
+					found = await globs.findHelpersAndTests({cwd: this.options.resolveTestsFrom, ...apiOptions.globs});
+					helpers = found.helpers;
+				} else {
+					found = await globs.findTests({cwd: this.options.resolveTestsFrom, ...apiOptions.globs});
+				}
+
 				if (files.length === 0) {
 					({tests: files} = found);
 				}
-
-				({helpers} = found);
 			}
 
 			if (this.options.parallelRuns) {

lib/cli.js

@@ -180,7 +180,7 @@ exports.run = async () => { // eslint-disable-line complexity
 
 	let globs;
 	try {
-		globs = normalizeGlobs(conf.files, conf.sources, extensions.all);
+		globs = normalizeGlobs(conf.files, conf.helpers, conf.sources, extensions.all);
 	} catch (error) {
 		exit(error.message);
 	}

lib/globs.js

@@ -28,11 +28,15 @@ const normalizePatterns = patterns => {
 	});
 };
 
-function normalizeGlobs(testPatterns, sourcePatterns, extensions) {
+function normalizeGlobs(testPatterns, helperPatterns, sourcePatterns, extensions) {
 	if (typeof testPatterns !== 'undefined' && (!Array.isArray(testPatterns) || testPatterns.length === 0)) {
 		throw new Error('The \'files\' configuration must be an array containing glob patterns.');
 	}
 
+	if (typeof helperPatterns !== 'undefined' && (!Array.isArray(helperPatterns) || helperPatterns.length === 0)) {
+		throw new Error('The \'helpers\' configuration must be an array containing glob patterns.');
+	}
+
 	if (sourcePatterns && (!Array.isArray(sourcePatterns) || sourcePatterns.length === 0)) {
 		throw new Error('The \'sources\' configuration must be an array containing glob patterns.');
 	}
@@ -58,6 +62,12 @@ function normalizeGlobs(testPatterns, sourcePatterns, extensions) {
 		testPatterns = defaultTestPatterns;
 	}
 
+	if (helperPatterns) {
+		helperPatterns = normalizePatterns(helperPatterns);
+	} else {
+		helperPatterns = [];
+	}
+
 	const defaultSourcePatterns = [
 		'**/*.snap',
 		'ava.config.js',
@@ -75,11 +85,13 @@ function normalizeGlobs(testPatterns, sourcePatterns, extensions) {
 		sourcePatterns = defaultSourcePatterns;
 	}
 
-	return {extensions, testPatterns, sourcePatterns};
+	return {extensions, testPatterns, helperPatterns, sourcePatterns};
 }
 
 exports.normalizeGlobs = normalizeGlobs;
 
+const hasExtension = (extensions, file) => extensions.includes(path.extname(file).slice(1));
+
 const findFiles = async (cwd, patterns) => {
 	const files = await globby(patterns, {
 		absolute: true,
@@ -108,26 +120,60 @@ const findFiles = async (cwd, patterns) => {
 	return files;
 };
 
-async function findHelpersAndTests({cwd, extensions, testPatterns}) {
-	const helpers = [];
+async function findHelpersAndTests({cwd, extensions, testPatterns, helperPatterns}) {
+	// Search for tests concurrently with finding helpers.
+	const findingTests = findFiles(cwd, testPatterns);
+
+	const uniqueHelpers = new Set();
+	if (helperPatterns.length > 0) {
+		for (const file of await findFiles(cwd, helperPatterns)) {
+			if (!hasExtension(extensions, file)) {
+				continue;
+			}
+
+			uniqueHelpers.add(file);
+		}
+	}
+
 	const tests = [];
-	for (const file of await findFiles(cwd, testPatterns)) {
-		if (!extensions.includes(path.extname(file).slice(1))) {
+	for (const file of await findingTests) {
+		if (!hasExtension(extensions, file)) {
 			continue;
 		}
 
 		if (path.basename(file).startsWith('_')) {
-			helpers.push(file);
-		} else {
+			uniqueHelpers.add(file);
+		} else if (!uniqueHelpers.has(file)) { // Helpers cannot be tests.
 			tests.push(file);
 		}
 	}
 
-	return {helpers, tests};
+	return {helpers: [...uniqueHelpers], tests};
 }
 
 exports.findHelpersAndTests = findHelpersAndTests;
 
+async function findTests({cwd, extensions, testPatterns, helperPatterns}) {
+	const rejectHelpers = helperPatterns.length > 0;
+
+	const tests = [];
+	for (const file of await findFiles(cwd, testPatterns)) {
+		if (!hasExtension(extensions, file) || path.basename(file).startsWith('_')) {
+			continue;
+		}
+
+		if (rejectHelpers && matches(file, helperPatterns)) {
+			continue;
+		}
+
+		tests.push(file);
+	}
+
+	return {tests};
+}
+
+exports.findTests = findTests;
+
 function getChokidarPatterns({sourcePatterns, testPatterns}) {
 	const paths = [];
 	const ignored = defaultIgnorePatterns.map(pattern => `${pattern}/**/*`);
@@ -175,10 +221,33 @@ const matches = (file, patterns) => {
 	return micromatch.some(file, patterns, {ignore});
 };
 
-function classify(file, {testPatterns, sourcePatterns}) {
-	const isHelper = path.basename(file).startsWith('_');
-	const isTest = !isHelper && matches(file, testPatterns);
-	const isSource = !isHelper && !isTest && matches(file, sourcePatterns);
+const NOT_IGNORED = ['**/*'];
+
+function classify(file, {extensions, helperPatterns, testPatterns, sourcePatterns}) {
+	let isHelper = false;
+	let isTest = false;
+	let isSource = false;
+
+	if (hasExtension(extensions, file)) {
+		if (path.basename(file).startsWith('_')) {
+			isHelper = matches(file, NOT_IGNORED);
+		} else {
+			isHelper = helperPatterns.length > 0 && matches(file, helperPatterns);
+
+			if (!isHelper) {
+				isTest = testPatterns.length > 0 && matches(file, testPatterns);
+
+				if (!isTest) {
+					// Note: Don't check sourcePatterns.length since we still need to
+					// check the file against the default ignore patterns.
+					isSource = matches(file, sourcePatterns);
+				}
+			}
+		}
+	} else {
+		isSource = matches(file, sourcePatterns);
+	}
+
 	return {isHelper, isTest, isSource};
 }
 

test/api.js

@@ -32,7 +32,7 @@ function apiCreator(options = {}) {
 	options.babelConfig = babelPipeline.validate(options.babelConfig);
 	options.concurrency = 2;
 	options.extensions = options.extensions || {all: ['js'], enhancementsOnly: [], full: ['js']};
-	options.globs = normalizeGlobs(options.files, options.sources, options.extensions.all);
+	options.globs = normalizeGlobs(options.files, options.helpers, options.sources, options.extensions.all);
 	options.projectDir = options.projectDir || ROOT_DIR;
 	options.resolveTestsFrom = options.resolveTestsFrom || options.projectDir;
 	const instance = new Api(options);
@@ -579,16 +579,15 @@ test('test file in node_modules is ignored', t => {
 		});
 });
 
-// TODO: Re-enable to test helpers patterns.
-// test('test file in helpers is ignored', t => {
-// 	t.plan(1);
-//
-// 	const api = apiCreator();
-// 	return api.run([path.join(__dirname, 'fixture/ignored-dirs/helpers/test.js')])
-// 		.then(runStatus => {
-// 			t.is(runStatus.stats.declaredTests, 0);
-// 		});
-// });
+test('test file in helpers is ignored', t => {
+	t.plan(1);
+
+	const api = apiCreator({helpers: ['**/helpers/*'], projectDir: path.join(__dirname, 'fixture/ignored-dirs')});
+	return api.run()
+		.then(runStatus => {
+			t.is(runStatus.stats.declaredTests, 1);
+		});
+});
 
 test('Node.js-style --require CLI argument', t => {
 	const requirePath = './' + path.relative('.', path.join(__dirname, 'fixture/install-global.js')).replace(/\\/g, '/');

test/fixture/globs/default-patterns/sub/directory/__tests__/helpers/foo.ts

@@ -0,0 +1 @@
+// Empty

test/fixture/ignored-dirs/test.js

@@ -0,0 +1,3 @@
+import test from '../../..';
+
+test('pass', t => t.pass());

test/fixture/invalid-globs/helpers/package.json

@@ -0,0 +1,5 @@
+{
+	"ava": {
+		"helpers": []
+	}
+}