rollup · Rich-Harris · Dec 30, 2015 · Dec 30, 2015
diff --git a/package.json b/package.json
@@ -57,7 +57,8 @@
     "rollup-plugin-replace": "^1.0.1",
     "sander": "^0.4.0",
     "source-map": "^0.5.3",
-    "sourcemap-codec": "^1.2.1"
+    "sourcemap-codec": "^1.2.1",
+    "uglify-js": "^2.6.1"
   },
   "dependencies": {
     "chalk": "^1.1.1",

diff --git a/src/Bundle.js b/src/Bundle.js
@@ -11,6 +11,7 @@ import getExportMode from './utils/getExportMode.js';
 import getIndentString from './utils/getIndentString.js';
 import { unixizePath } from './utils/normalizePlatform.js';
 import transform from './utils/transform.js';
+import transformBundle from './utils/transformBundle.js';
 import collapseSourcemaps from './utils/collapseSourcemaps.js';
 import callIfFunction from './utils/callIfFunction.js';
 import { isRelative } from './utils/path.js';
@@ -46,6 +47,10 @@ export default class Bundle {
 			.map( plugin => plugin.transform )
 			.filter( Boolean );
 
+		this.bundleTransformers = this.plugins
+			.map( plugin => plugin.transformBundle )
+			.filter( Boolean );
+
 		this.moduleById = blank();
 		this.modules = [];
 
@@ -257,7 +262,7 @@ export default class Bundle {
 			map.sources = map.sources.map( unixizePath );
 		}
 
-		return { code, map };
+		return transformBundle( { code, map }, this.bundleTransformers );
 	}
 
 	sort () {

diff --git a/src/utils/transformBundle.js b/src/utils/transformBundle.js
@@ -0,0 +1,39 @@
+import MagicString from 'magic-string';
+
+export default function transformBundle ( source, transformers ) {
+	if ( typeof source === 'string' ) {
+		source = {
+			code: source,
+			map: null
+		};
+	}
+
+	return transformers.reduce( ( previous, transformer ) => {
+		let result = transformer( previous.code, previous.map );
+
+		if ( result == null ) return previous;
+
+		if ( typeof result === 'string' ) {
+			result = {
+				code: result,
+				map: null
+			};
+		}
+		// `result.map` can only be a string if `result` isn't
+		else if ( typeof result.map === 'string' ) {
+			result.map = JSON.parse( result.map );
+		}
+
+		if (result.map != null) {
+			let map = new MagicString.Bundle().generateMap({});
+			map.file = result.map.file;
+			map.sources = result.map.sources;
+			map.sourcesContent = result.map.sourcesContent;
+			map.names = result.map.names;
+			map.mappings = result.map.mappings;
+			result.map = map;
+		}
+
+		return result;
+	}, source );
+}
diff --git a/test/form/transform-bundle-plugin/_config.js b/test/form/transform-bundle-plugin/_config.js
@@ -0,0 +1,17 @@
+module.exports = {
+	description: 'allows plugins to transform bundle',
+	options: {
+		plugins: [
+			{
+				transformBundle: function (code) {
+					return '/* first plugin */';
+				}
+			},
+			{
+				transformBundle: function (code) {
+					return code + '\n/* second plugin */';
+				}
+			}
+		]
+	}
+}
diff --git a/test/form/transform-bundle-plugin/_expected/amd.js b/test/form/transform-bundle-plugin/_expected/amd.js
@@ -0,0 +1,2 @@
+/* first plugin */
+/* second plugin */
diff --git a/test/form/transform-bundle-plugin/_expected/cjs.js b/test/form/transform-bundle-plugin/_expected/cjs.js
@@ -0,0 +1,2 @@
+/* first plugin */
+/* second plugin */
diff --git a/test/form/transform-bundle-plugin/_expected/es6.js b/test/form/transform-bundle-plugin/_expected/es6.js
@@ -0,0 +1,2 @@
+/* first plugin */
+/* second plugin */
diff --git a/test/form/transform-bundle-plugin/_expected/iife.js b/test/form/transform-bundle-plugin/_expected/iife.js
@@ -0,0 +1,2 @@
+/* first plugin */
+/* second plugin */
diff --git a/test/form/transform-bundle-plugin/_expected/umd.js b/test/form/transform-bundle-plugin/_expected/umd.js
@@ -0,0 +1,2 @@
+/* first plugin */
+/* second plugin */
diff --git a/test/form/transform-bundle-plugin/main.js b/test/form/transform-bundle-plugin/main.js
@@ -0,0 +1 @@
+console.log( 1 + 1 );
diff --git a/test/sourcemaps/transform-bundle/_config.js b/test/sourcemaps/transform-bundle/_config.js
@@ -0,0 +1,47 @@
+var uglify = require( 'uglify-js' );
+var MagicString = require( 'magic-string' );
+var assert = require( 'assert' );
+var getLocation = require( '../../utils/getLocation' );
+var SourceMapConsumer = require( 'source-map' ).SourceMapConsumer;
+
+module.exports = {
+	description: 'preserves sourcemap chains when transforming',
+	options: {
+		plugins: [
+			{
+				transformBundle: function ( code, map ) {
+					var options = { fromString: true };
+
+					if ( map != null ) {
+						options.inSourceMap = map;
+						options.outSourceMap = "out";
+					}
+
+					var result = uglify.minify( code, options );
+
+					if ( map != null ) {
+						result.code = result.code.slice( 0, -25 );
+					}
+
+					return result;
+				}
+			}
+		]
+	},
+	test: function ( code, map ) {
+		var smc = new SourceMapConsumer( map );
+
+		var generatedLoc = getLocation( code, code.indexOf( '42' ) );
+		var originalLoc = smc.originalPositionFor( generatedLoc );
+
+		assert.ok( /main/.test( originalLoc.source ) );
+		assert.equal( originalLoc.line, 1 );
+		assert.equal( originalLoc.column, 13 );
+
+		generatedLoc = getLocation( code, code.indexOf( 'log' ) );
+		originalLoc = smc.originalPositionFor( generatedLoc );
+
+		assert.equal( originalLoc.line, 1 );
+		assert.equal( originalLoc.column, 8 );
+	}
+};
diff --git a/test/sourcemaps/transform-bundle/main.js b/test/sourcemaps/transform-bundle/main.js
@@ -0,0 +1 @@
+console.log( 42 );