Make test & helper file extensions configurable

Allow configuration of test & helper file extensions. Files will be recognized when searching for tests. Users can choose whether the files should participate in the Babel precompilation.

api.js

@@ -3,6 +3,7 @@ const path = require('path');
 const fs = require('fs');
 const os = require('os');
 const commonPathPrefix = require('common-path-prefix');
+const escapeStringRegexp = require('escape-string-regexp');
 const uniqueTempDir = require('unique-temp-dir');
 const isCi = require('is-ci');
 const resolveCwd = require('resolve-cwd');
@@ -38,6 +39,8 @@ class Api extends Emittery {
 		this.options = Object.assign({match: []}, options);
 		this.options.require = resolveModules(this.options.require);
 
+		this._allExtensions = this.options.extensions.all;
+		this._regexpFullExtensions = new RegExp(`\\.(${this.options.extensions.full.map(ext => escapeStringRegexp(ext)).join('|')})$`);
 		this._precompiler = null;
 	}
 
@@ -78,7 +81,7 @@ class Api extends Emittery {
 		}
 
 		// Find all test files.
-		return new AvaFiles({cwd: apiOptions.resolveTestsFrom, files}).findTestFiles()
+		return new AvaFiles({cwd: apiOptions.resolveTestsFrom, files, extensions: this._allExtensions}).findTestFiles()
 			.then(files => {
 				runStatus = new RunStatus(files.length);
 
@@ -122,31 +125,35 @@ class Api extends Emittery {
 				return emittedRun
 					.then(() => this._setupPrecompiler())
 					.then(precompilation => {
-						if (!precompilation.precompileFile) {
+						if (!precompilation.enabled) {
 							return null;
 						}
 
 						// Compile all test and helper files. Assumes the tests only load
 						// helpers from within the `resolveTestsFrom` directory. Without
 						// arguments this is the `projectDir`, else it's `process.cwd()`
 						// which may be nested too deeply.
-						return new AvaFiles({cwd: this.options.resolveTestsFrom}).findTestHelpers().then(helpers => {
-							return {
-								cacheDir: precompilation.cacheDir,
-								map: [...files, ...helpers].reduce((acc, file) => {
-									try {
-										const realpath = fs.realpathSync(file);
-										const cachePath = precompilation.precompileFile(realpath);
-										if (cachePath) {
-											acc[realpath] = cachePath;
+						return new AvaFiles({cwd: this.options.resolveTestsFrom, extensions: this._allExtensions})
+							.findTestHelpers().then(helpers => {
+								return {
+									cacheDir: precompilation.cacheDir,
+									map: [...files, ...helpers].reduce((acc, file) => {
+										try {
+											const realpath = fs.realpathSync(file);
+											const filename = path.basename(realpath);
+											const cachePath = this._regexpFullExtensions.test(filename) ?
+												precompilation.precompileFull(realpath) :
+												precompilation.precompileEnhancementsOnly(realpath);
+											if (cachePath) {
+												acc[realpath] = cachePath;
+											}
+										} catch (err) {
+											throw Object.assign(err, {file});
 										}
-									} catch (err) {
-										throw Object.assign(err, {file});
-									}
-									return acc;
-								}, {})
-							};
-						});
+										return acc;
+									}, {})
+								};
+							});
 					})
 					.then(precompilation => {
 						// Resolve the correct concurrency value.
@@ -218,10 +225,24 @@ class Api extends Emittery {
 		// Ensure cacheDir exists
 		makeDir.sync(cacheDir);
 
-		const {projectDir, babelConfig, compileEnhancements} = this.options;
+		const {projectDir, babelConfig} = this.options;
+		const compileEnhancements = this.options.compileEnhancements !== false;
+		const precompileFull = babelConfig ?
+			babelPipeline.build(projectDir, cacheDir, babelConfig, compileEnhancements) :
+			filename => {
+				throw new Error(`Cannot apply full precompilation, possible bad usage: ${filename}`);
+			};
+		const precompileEnhancementsOnly = compileEnhancements && this.options.extensions.enhancementsOnly.length > 0 ?
+			babelPipeline.build(projectDir, cacheDir, null, compileEnhancements) :
+			filename => {
+				throw new Error(`Cannot apply enhancement-only precompilation, possible bad usage: ${filename}`);
+			};
+
 		this._precompiler = {
 			cacheDir,
-			precompileFile: babelPipeline.build(projectDir, cacheDir, babelConfig, compileEnhancements !== false)
+			enabled: babelConfig || compileEnhancements,
+			precompileEnhancementsOnly,
+			precompileFull
 		};
 		return this._precompiler;
 	}

docs/recipes/babel.md

@@ -37,6 +37,25 @@ Instead run the following to reset AVA's cache when you change the configuration
 $ npx ava --reset-cache
 ```
 
+## Add additional extensions
+
+You can configure AVA to recognize additional file extensions and compile those test & helper files using Babel:
+
+```json
+{
+	"ava": {
+		"babel": {
+			"extensions": [
+				"js",
+				"jsx"
+			]
+		}
+	}
+}
+```
+
+See also AVA's [`extensions` option](../../readme.md#options).
+
 ## Make AVA skip your project's Babel options
 
 You may not want AVA to use your project's Babel options, for example if your project is relying on Babel 6. You can set the `babelrc` option to `false`:

docs/recipes/es-modules.md

@@ -45,4 +45,43 @@ test('2 + 2 = 4', t => {
 });
 ```
 
-Note that test files still need to use the `.js` extension.
+You need to configure AVA to recognize `.mjs` extensions. If you want AVA to apply its Babel presets use:
+
+```json
+{
+	"ava": {
+		"babel": {
+			"extensions": [
+				"js",
+				"mjs"
+			]
+		}
+	}
+}
+```
+
+Alternatively you can use:
+
+```json
+{
+	"ava": {
+		"babel": false,
+		"extensions": [
+			"js",
+			"mjs"
+		]
+	}
+}
+```
+
+Or leave Babel enabled (which means it's applied to `.js` files), but don't apply it to `.mjs` files:
+
+```json
+{
+	"ava": {
+		"extensions": [
+			"mjs"
+		]
+	}
+}
+```

lib/ava-files.js

@@ -9,7 +9,7 @@ const autoBind = require('auto-bind');
 const defaultIgnore = require('ignore-by-default').directories();
 const multimatch = require('multimatch');
 
-function handlePaths(files, excludePatterns, globOptions) {
+function handlePaths(files, extensions, excludePatterns, globOptions) {
 	// Convert Promise to Bluebird
 	files = Promise.resolve(globby(files.concat(excludePatterns), globOptions));
 
@@ -42,22 +42,23 @@ function handlePaths(files, excludePatterns, globOptions) {
 
 				searchedParents.add(file);
 
-				let pattern = path.join(file, '**', '*.js');
+				let pattern = path.join(file, '**', `*.${extensions.length === 1 ?
+					extensions[0] : `{${extensions.join(',')}}`}`);
 
 				if (process.platform === 'win32') {
 					// Always use `/` in patterns, harmonizing matching across platforms
 					pattern = slash(pattern);
 				}
 
-				return handlePaths([pattern], excludePatterns, globOptions);
+				return handlePaths([pattern], extensions, excludePatterns, globOptions);
 			}
 
 			// `globby` returns slashes even on Windows. Normalize here so the file
 			// paths are consistently platform-accurate as tests are run.
 			return path.normalize(file);
 		})
 		.then(flatten)
-		.filter(file => file && path.extname(file) === '.js')
+		.filter(file => file && extensions.includes(path.extname(file).substr(1)))
 		.filter(file => {
 			if (path.basename(file)[0] === '_' && globOptions.includeUnderscoredFiles !== true) {
 				return false;
@@ -79,19 +80,19 @@ const defaultExcludePatterns = () => [
 	'!**/helpers/**'
 ];
 
-const defaultIncludePatterns = () => [
-	'test.js',
-	'test-*.js',
-	'test',
-	'**/__tests__',
-	'**/*.test.js'
+const defaultIncludePatterns = extPattern => [
+	`test.${extPattern}`,
+	`test-*.${extPattern}`,
+	'test', // Directory
+	'**/__tests__', // Directory
+	`**/*.test.${extPattern}`
 ];
 
-const defaultHelperPatterns = () => [
-	'**/__tests__/helpers/**/*.js',
-	'**/__tests__/**/_*.js',
-	'**/test/helpers/**/*.js',
-	'**/test/**/_*.js'
+const defaultHelperPatterns = extPattern => [
+	`**/__tests__/helpers/**/*.${extPattern}`,
+	`**/__tests__/**/_*.${extPattern}`,
+	`**/test/helpers/**/*.${extPattern}`,
+	`**/test/**/_*.${extPattern}`
 ];
 
 const getDefaultIgnorePatterns = () => defaultIgnore.map(dir => `${dir}/**/*`);
@@ -114,11 +115,13 @@ class AvaFiles {
 			return file;
 		});
 
+		this.extensions = options.extensions || ['js'];
+		this.extensionPattern = this.extensions.length === 1 ?
+			this.extensions[0] : `{${this.extensions.join(',')}}`;
+		this.excludePatterns = defaultExcludePatterns();
 		if (files.length === 0) {
-			files = defaultIncludePatterns();
+			files = defaultIncludePatterns(this.extensionPattern);
 		}
-
-		this.excludePatterns = defaultExcludePatterns();
 		this.files = files;
 		this.sources = options.sources || [];
 		this.cwd = options.cwd || process.cwd();
@@ -133,15 +136,15 @@ class AvaFiles {
 	}
 
 	findTestFiles() {
-		return handlePaths(this.files, this.excludePatterns, Object.assign({
+		return handlePaths(this.files, this.extensions, this.excludePatterns, Object.assign({
 			cwd: this.cwd,
 			expandDirectories: false,
 			nodir: false
 		}, this.globCaches));
 	}
 
 	findTestHelpers() {
-		return handlePaths(defaultHelperPatterns(), ['!**/node_modules/**'], Object.assign({
+		return handlePaths(defaultHelperPatterns(this.extensionPattern), this.extensions, ['!**/node_modules/**'], Object.assign({
 			cwd: this.cwd,
 			includeUnderscoredFiles: true,
 			expandDirectories: false,
@@ -151,7 +154,7 @@ class AvaFiles {
 
 	isSource(filePath) {
 		let mixedPatterns = [];
-		const defaultIgnorePatterns = getDefaultIgnorePatterns();
+		const defaultIgnorePatterns = getDefaultIgnorePatterns(this.extensionPattern);
 		const overrideDefaultIgnorePatterns = [];
 
 		let hasPositivePattern = false;

lib/babel-pipeline.js

@@ -4,6 +4,7 @@ const path = require('path');
 const writeFileAtomic = require('@ava/write-file-atomic');
 const babel = require('@babel/core');
 const convertSourceMap = require('convert-source-map');
+const isPlainObject = require('is-plain-object');
 const md5Hex = require('md5-hex');
 const packageHash = require('package-hash');
 const stripBomBuf = require('strip-bom-buf');
@@ -20,6 +21,14 @@ function getSourceMap(filePath, code) {
 	return sourceMap ? sourceMap.toObject() : undefined;
 }
 
+function hasValidKeys(conf) {
+	return Object.keys(conf).every(key => key === 'extensions' || key === 'testOptions');
+}
+
+function isValidExtensions(extensions) {
+	return Array.isArray(extensions) && extensions.every(ext => typeof ext === 'string' && ext !== '');
+}
+
 function validate(conf) {
 	if (conf === false) {
 		return null;
@@ -31,11 +40,17 @@ function validate(conf) {
 		return {testOptions: defaultOptions};
 	}
 
-	if (!conf || typeof conf !== 'object' || !conf.testOptions || typeof conf.testOptions !== 'object' || Array.isArray(conf.testOptions) || Object.keys(conf).length > 1) {
+	if (
+		!isPlainObject(conf) ||
+		!hasValidKeys(conf) ||
+		(conf.testOptions !== undefined && !isPlainObject(conf.testOptions)) ||
+		(conf.extensions !== undefined && !isValidExtensions(conf.extensions))
+	) {
 		throw new Error(`Unexpected Babel configuration for AVA. See ${chalk.underline('https://github.com/avajs/ava/blob/master/docs/recipes/babel.md')} for allowed values.`);
 	}
 
 	return {
+		extensions: conf.extensions,
 		testOptions: Object.assign({}, defaultOptions, conf.testOptions)
 	};
 }

lib/cli.js

@@ -149,6 +149,7 @@ exports.run = () => { // eslint-disable-line complexity
 	const TapReporter = require('./reporters/tap');
 	const Watcher = require('./watcher');
 	const babelPipeline = require('./babel-pipeline');
+	const normalizeExtensions = require('./extensions');
 
 	let babelConfig = null;
 	try {
@@ -157,6 +158,13 @@ exports.run = () => { // eslint-disable-line complexity
 		exit(err.message);
 	}
 
+	let extensions;
+	try {
+		extensions = normalizeExtensions(conf.extensions || [], babelConfig);
+	} catch (err) {
+		exit(err.message);
+	}
+
 	// Copy resultant cli.flags into conf for use with Api and elsewhere
 	Object.assign(conf, cli.flags);
 
@@ -168,6 +176,7 @@ exports.run = () => { // eslint-disable-line complexity
 		require: arrify(conf.require),
 		cacheEnabled: conf.cache !== false,
 		compileEnhancements: conf.compileEnhancements !== false,
+		extensions,
 		match,
 		babelConfig,
 		resolveTestsFrom: cli.input.length === 0 ? projectDir : process.cwd(),