Change Babel configuration format

Remove 'default' and 'inherits' options, since 'inherits' is now the
default.

In preparation for custom extension support and source compilation, move
options for test compilation into the `testOptions` field.

Author: novemberborn

lib/babel-config.js

@@ -14,14 +14,11 @@ const syntaxObjectRestSpreadPath = require.resolve('@babel/plugin-syntax-object-
 const transformTestFilesPath = require.resolve('@ava/babel-preset-transform-test-files');
 
 function validate(conf) {
-	if (conf === undefined || conf === null) {
-		conf = 'default';
+	if (conf === undefined) {
+		return {testOptions: {}};
 	}
 
-	// Check for valid babel config shortcuts (can be either `default` or `inherit`)
-	const isValidShortcut = conf === 'default' || conf === 'inherit';
-
-	if (!conf || (typeof conf === 'string' && !isValidShortcut)) {
+	if (!conf || typeof conf !== 'object' || !conf.testOptions || typeof conf.testOptions !== 'object' || Array.isArray(conf.testOptions) || Object.keys(conf).length > 1) {
 		let message = colors.error(figures.cross);
 		message += ' Unexpected Babel configuration for AVA. ';
 		message += 'See ' + chalk.underline('https://github.com/avajs/ava#es2017-support') + ' for allowed values.';
@@ -115,12 +112,12 @@ function build(projectDir, cacheDir, userOptions, compileEnhancements) {
 	};
 
 	// By default extend the project's Babel configuration, but allow this to be
-	// disabled in userOptions.
-	if (userOptions === 'default' || userOptions === 'inherit' || userOptions.babelrc !== false) {
+	// disabled through userOptions.
+	if (userOptions.testOptions.babelrc !== false) {
 		baseOptions.babelrc = true;
 	}
-	if (userOptions.extends) {
-		baseOptions.extends = userOptions.extends;
+	if (userOptions.testOptions.extends) {
+		baseOptions.extends = userOptions.testOptions.extends;
 	}
 
 	// Include object rest spread support for Node.js versions that support it
@@ -138,9 +135,9 @@ function build(projectDir, cacheDir, userOptions, compileEnhancements) {
 	});
 
 	let intermediateConfig = baseConfig;
-	if (userOptions !== 'default' && userOptions !== 'inherit') {
+	if (Object.keys(userOptions.testOptions).length > 0) {
 		// At this level, babelrc *must* be false.
-		const options = Object.assign({}, userOptions, {babelrc: false});
+		const options = Object.assign({}, userOptions.testOptions, {babelrc: false});
 		// Any extends option has been applied in baseConfig.
 		delete options.extends;
 		intermediateConfig = configManager.createConfig({

profile.js

@@ -37,7 +37,9 @@ Promise.longStackTraces();
 
 const conf = pkgConf.sync('ava', {
 	defaults: {
-		babel: 'default'
+		babel: {
+			testOptions: {}
+		}
 	}
 });
 
@@ -76,7 +78,7 @@ const cacheDir = findCacheDir({
 	files: [file]
 }) || uniqueTempDir();
 
-babelConfigHelper.build(process.cwd(), cacheDir, conf.babel, true)
+babelConfigHelper.build(process.cwd(), cacheDir, babelConfigHelper.validate(conf.babel), true)
 	.then(result => {
 		const precompiler = new CachingPrecompiler({
 			path: cacheDir,

test/api.js

@@ -12,7 +12,7 @@ const ROOT_DIR = path.join(__dirname, '..');
 
 function apiCreator(options) {
 	options = options || {};
-	options.babelConfig = options.babelConfig || 'default';
+	options.babelConfig = options.babelConfig || {testOptions: {}};
 	options.projectDir = options.projectDir || ROOT_DIR;
 	options.resolveTestsFrom = options.resolveTestsFrom || options.projectDir;
 	const instance = new Api(options);
@@ -817,13 +817,14 @@ function generateTests(prefix, apiCreator) {
 		});
 	});
 
-	test(`${prefix} Custom Babel Plugin Support`, t => {
+	test(`${prefix} babel.testOptions with a custom plugin`, t => {
 		t.plan(2);
 
 		const api = apiCreator({
 			babelConfig: {
-				presets: ['@ava/stage-4'],
-				plugins: [testCapitalizerPlugin]
+				testOptions: {
+					plugins: [testCapitalizerPlugin]
+				}
 			},
 			cacheEnabled: false,
 			projectDir: __dirname
@@ -841,31 +842,10 @@ function generateTests(prefix, apiCreator) {
 			}, t.threw);
 	});
 
-	test(`${prefix} Default babel config uses .babelrc`, t => {
-		t.plan(3);
-
-		const api = apiCreator({
-			projectDir: path.join(__dirname, 'fixture/babelrc')
-		});
-
-		api.on('test-run', runStatus => {
-			runStatus.on('test', data => {
-				t.ok((data.title === 'foo') || (data.title === 'repeated test: foo'));
-			});
-		});
-
-		return api.run()
-			.then(result => {
-				t.is(result.passCount, 2);
-			});
-	});
-
-	test(`${prefix} babelConfig:"inherit" uses .babelrc`, t => {
+	test(`${prefix} babel.testOptions.babelrc effectively defaults to true`, t => {
 		t.plan(3);
 
 		const api = apiCreator({
-			babelConfig: 'inherit',
-			cacheEnabled: false,
 			projectDir: path.join(__dirname, 'fixture/babelrc')
 		});
 
@@ -881,11 +861,13 @@ function generateTests(prefix, apiCreator) {
 			});
 	});
 
-	test(`${prefix} babelConfig:{babelrc:true} uses .babelrc`, t => {
+	test(`${prefix} babel.testOptions.babelrc can explicitly be true`, t => {
 		t.plan(3);
 
 		const api = apiCreator({
-			babelConfig: {babelrc: true},
+			babelConfig: {
+				testOptions: {babelrc: true}
+			},
 			cacheEnabled: false,
 			projectDir: path.join(__dirname, 'fixture/babelrc')
 		});
@@ -902,11 +884,13 @@ function generateTests(prefix, apiCreator) {
 			});
 	});
 
-	test(`${prefix} babelConfig:{babelrc:false} does not use .babelrc`, t => {
+	test(`${prefix} babel.testOptions.babelrc can explicitly be false`, t => {
 		t.plan(2);
 
 		const api = apiCreator({
-			babelConfig: {babelrc: false},
+			babelConfig: {
+				testOptions: {babelrc: false}
+			},
 			cacheEnabled: false,
 			projectDir: path.join(__dirname, 'fixture/babelrc')
 		});
@@ -923,13 +907,15 @@ function generateTests(prefix, apiCreator) {
 			});
 	});
 
-	test(`${prefix} babelConfig:{babelrc:true, plugins:[...]} merges plugins with .babelrc`, t => {
+	test(`${prefix} babelConfig.testOptions merges plugins with .babelrc`, t => {
 		t.plan(3);
 
 		const api = apiCreator({
 			babelConfig: {
-				plugins: [testCapitalizerPlugin],
-				babelrc: true
+				testOptions: {
+					babelrc: true,
+					plugins: [testCapitalizerPlugin]
+				}
 			},
 			cacheEnabled: false,
 			projectDir: path.join(__dirname, 'fixture/babelrc')
@@ -947,13 +933,15 @@ function generateTests(prefix, apiCreator) {
 			});
 	});
 
-	test(`${prefix} babelConfig:{extends:path, plugins:[...]} merges plugins with .babelrc`, t => {
+	test(`${prefix} babelConfig.testOptions with extends still merges plugins with .babelrc`, t => {
 		t.plan(3);
 
 		const api = apiCreator({
 			babelConfig: {
-				plugins: [testCapitalizerPlugin],
-				extends: path.join(__dirname, 'fixture/babelrc/.alt-babelrc')
+				testOptions: {
+					plugins: [testCapitalizerPlugin],
+					extends: path.join(__dirname, 'fixture/babelrc/.alt-babelrc')
+				}
 			},
 			cacheEnabled: false,
 			projectDir: path.join(__dirname, 'fixture/babelrc')