deconflict external imports

src/Bundle.js

@@ -91,16 +91,14 @@ export default class Bundle {
 
 		// Assign names to external modules
 		this.externalModules.forEach( module => {
-			// TODO is this right?
 			let name = makeLegalIdentifier( module.suggestedNames['*'] || module.suggestedNames.default || module.id );
 
-			if ( definers[ name ] ) {
+			while ( definers[ name ] ) {
 				conflicts[ name ] = true;
-			} else {
-				definers[ name ] = [];
+				name = `_${name}`;
 			}
 
-			definers[ name ].push( module );
+			definers[ name ] = [ module ];
 			module.name = name;
 			this.assumedGlobals[ name ] = true;
 		});

test/function/deconflicts-external-imports/_config.js

@@ -0,0 +1,13 @@
+module.exports = {
+	description: 'deconflicts external imports',
+	context: {
+		require: function ( id ) {
+			return function () {
+				return id;
+			};
+		}
+	},
+	options: {
+		external: [ 'foo', 'bar' ]
+	}
+};

test/function/deconflicts-external-imports/a.js

@@ -0,0 +1,5 @@
+import foo from 'foo';
+
+export default function () {
+	assert.equal( foo(), 'foo' );
+}

test/function/deconflicts-external-imports/b.js

@@ -0,0 +1,5 @@
+import foo from 'bar';
+
+export default function () {
+	assert.equal( foo(), 'bar' );
+}

test/function/deconflicts-external-imports/main.js

@@ -0,0 +1,5 @@
+import a from './a';
+import b from './b';
+
+a();
+b();