Transpile only default babel extensions, allow for custom extensions …

…option (fixes #111)

packages/rollup-plugin-babel/package.json

@@ -47,6 +47,7 @@
     "mocha": "^5.2.0",
     "rollup": "^0.62.0",
     "rollup-plugin-buble": "^0.19.2",
+    "rollup-plugin-json": "^3.0.0",
     "source-map": "^0.6.1",
     "source-map-support": "^0.5.6"
   },

packages/rollup-plugin-babel/src/index.js

@@ -1,12 +1,13 @@
 import { dirname } from 'path';
-import { buildExternalHelpers, transform } from '@babel/core';
+import { buildExternalHelpers, DEFAULT_EXTENSIONS, transform } from '@babel/core';
 import { createFilter } from 'rollup-pluginutils';
 import createPreflightCheck from './preflightCheck.js';
 import helperPlugin from './helperPlugin.js';
-import { warnOnce } from './utils.js';
+import { escapeRegExpCharacters, warnOnce } from './utils.js';
 import { RUNTIME, EXTERNAL, HELPERS } from './constants.js';
 
 const unpackOptions = ({
+	extensions = DEFAULT_EXTENSIONS,
 	// rollup uses sourcemap, babel uses sourceMaps
 	// just normalize them here so people don't have to worry about it
 	sourcemap = true,
@@ -15,21 +16,25 @@ const unpackOptions = ({
 	sourceMaps = true,
 	...rest
 } = {}) => ({
+	extensions,
 	sourceMaps: sourcemap && sourcemaps && sourceMap && sourceMaps,
-	...rest
+	...rest,
 });
 
 export default function babel ( options ) {
 	const {
 		exclude,
+		extensions,
 		externalHelpers,
 		externalHelpersWhitelist,
 		include,
 		runtimeHelpers,
 		...babelOptions
 	} = unpackOptions(options);
 
-	const filter = createFilter( include, exclude );
+	const extensionRegExp = new RegExp(`(${extensions.map(escapeRegExpCharacters).join('|')})$`);
+	const includeExcludeFilter = createFilter( include, exclude );
+	const filter = id => extensionRegExp.test(id) && includeExcludeFilter(id);
 	const preflightCheck = createPreflightCheck();
 
 	return {

packages/rollup-plugin-babel/src/utils.js

@@ -4,3 +4,6 @@ export function warnOnce ( ctx, msg ) {
 	warned[ msg ] = true;
 	ctx.warn( msg );
 }
+
+const regExpCharactersRegExp = /[\\^$.*+?()[\]{}|]/g;
+export const escapeRegExpCharacters = str => str.replace(regExpCharactersRegExp, '\\$&');

packages/rollup-plugin-babel/test/samples/extensions-custom/ext.es

@@ -0,0 +1 @@
+export default class Es {}

packages/rollup-plugin-babel/test/samples/extensions-custom/ext.es6

@@ -0,0 +1 @@
+export default class Es6 {}

packages/rollup-plugin-babel/test/samples/extensions-custom/ext.js

@@ -0,0 +1 @@
+export default class Js {}

packages/rollup-plugin-babel/test/samples/extensions-custom/ext.jsx

@@ -0,0 +1 @@
+export default class Jsx {}

packages/rollup-plugin-babel/test/samples/extensions-custom/ext.mjs

@@ -0,0 +1 @@
+export default class Mjs {}

packages/rollup-plugin-babel/test/samples/extensions-custom/ext.other

@@ -0,0 +1 @@
+export default class Other {}

packages/rollup-plugin-babel/test/samples/extensions-custom/main.js

@@ -0,0 +1,6 @@
+export { default as Js } from './ext.js';
+export { default as Jsx } from './ext.jsx';
+export { default as Es6 } from './ext.es6';
+export { default as Es } from './ext.es';
+export { default as Mjs } from './ext.mjs';
+export { default as Other } from './ext.other';

packages/rollup-plugin-babel/test/samples/extensions-default/ext.es

@@ -0,0 +1 @@
+export default class Es {}

packages/rollup-plugin-babel/test/samples/extensions-default/ext.es6

@@ -0,0 +1 @@
+export default class Es6 {}

packages/rollup-plugin-babel/test/samples/extensions-default/ext.js

@@ -0,0 +1 @@
+export default class Js {}

packages/rollup-plugin-babel/test/samples/extensions-default/ext.json

@@ -0,0 +1 @@
+{"json": true}

packages/rollup-plugin-babel/test/samples/extensions-default/ext.jsx

@@ -0,0 +1 @@
+export default class Jsx {}

packages/rollup-plugin-babel/test/samples/extensions-default/ext.mjs

@@ -0,0 +1 @@
+export default class Mjs {}

packages/rollup-plugin-babel/test/samples/extensions-default/ext.other

@@ -0,0 +1 @@
+export default class Other {}

packages/rollup-plugin-babel/test/samples/extensions-default/main.js

@@ -0,0 +1,7 @@
+export { default as Js } from './ext.js';
+export { default as Jsx } from './ext.jsx';
+export { default as Es6 } from './ext.es6';
+export { default as Es } from './ext.es';
+export { default as Mjs } from './ext.mjs';
+export { default as Json } from './ext.json';
+export { default as Other } from './ext.other';

packages/rollup-plugin-babel/test/test.js

@@ -2,6 +2,7 @@ var assert = require( 'assert' );
 var path = require( 'path' );
 var rollup = require( 'rollup' );
 var SourceMapConsumer = require( 'source-map' ).SourceMapConsumer;
+var jsonPlugin = require( 'rollup-plugin-json' );
 var babelPlugin = require( '..' );
 
 // from ./src/constants
@@ -212,4 +213,30 @@ describe( 'rollup-plugin-babel', function () {
 			assert.ok( code.indexOf('class Ignored') !== -1 );
 		});
 	});
+
+	it( 'transpiles only files with default extensions', () => {
+		return bundle('samples/extensions-default/main.js', undefined, undefined, {
+			plugins: [babelPlugin(), jsonPlugin()],
+		}).then(({ code }) => {
+			assert.ok( code.indexOf('class Es ') === -1, 'should transpile .es' );
+			assert.ok( code.indexOf('class Es6 ') === -1, 'should transpile .es6' );
+			assert.ok( code.indexOf('class Js ') === -1, 'should transpile .js' );
+			assert.ok( code.indexOf('class Jsx ') === -1, 'should transpile .jsx' );
+			assert.ok( code.indexOf('class Mjs ') === -1, 'should transpile .mjs' );
+			assert.ok( code.indexOf('class Other ') !== -1, 'should not transpile .other' );
+		});
+	});
+
+	it( 'transpiles only files with whitelisted extensions', () => {
+		return bundle('samples/extensions-custom/main.js', {
+			extensions: ['.js', '.other']
+		}).then(({ code }) => {
+			assert.ok( code.indexOf('class Es ') !== -1, 'should not transpile .es' );
+			assert.ok( code.indexOf('class Es6 ') !== -1, 'should not transpile .es6' );
+			assert.ok( code.indexOf('class Js ') === -1, 'should transpile .js' );
+			assert.ok( code.indexOf('class Jsx ') !== -1, 'should not transpile .jsx' );
+			assert.ok( code.indexOf('class Mjs ') !== -1, 'should not transpile .mjs' );
+			assert.ok( code.indexOf('class Other ') === -1, 'should transpile .other' );
+		});
+	});
 });