From 5be634f20e39c110da6013b8a8d7ab00845c5e12 Mon Sep 17 00:00:00 2001
From: Rich-Harris <richard.a.harris@gmail.com>
Date: Sun, 28 Jun 2015 10:24:07 -0400
Subject: [PATCH] ensure unused default exports have legal name (fixes #33)

---
 src/Module.js                                 | 23 +++++++++----------
 .../function/rename-default-export/_config.js |  9 ++++++++
 test/function/rename-default-export/bar.js    |  3 +++
 test/function/rename-default-export/baz.js    |  5 ++++
 test/function/rename-default-export/foo.js    |  3 +++
 test/function/rename-default-export/main.js   |  7 ++++++
 6 files changed, 38 insertions(+), 12 deletions(-)
 create mode 100644 test/function/rename-default-export/_config.js
 create mode 100644 test/function/rename-default-export/bar.js
 create mode 100644 test/function/rename-default-export/baz.js
 create mode 100644 test/function/rename-default-export/foo.js
 create mode 100644 test/function/rename-default-export/main.js

diff --git a/src/Module.js b/src/Module.js
index c0900c4..83e87bc 100644
--- a/src/Module.js
+++ b/src/Module.js
@@ -12,6 +12,14 @@ import makeLegalIdentifier from './utils/makeLegalIdentifier';
 
 const emptyArrayPromise = Promise.resolve([]);
 
+function deconflict ( name, names ) {
+	while ( name in names ) {
+		name = `_${name}`;
+	}
+
+	return name;
+}
+
 export default class Module {
 	constructor ({ path, source, bundle }) {
 		this.source = source;
@@ -249,14 +257,9 @@ export default class Module {
 	}
 
 	getCanonicalName ( localName ) {
-		// Special case
-		if ( localName === 'default' && this.exports.default && this.exports.default.isModified ) {
+		if ( localName === 'default' && ( this.exports.default.isModified || !this.suggestedNames.default ) ) {
 			let canonicalName = makeLegalIdentifier( this.path.replace( this.bundle.base + '/', '' ).replace( /\.js$/, '' ) );
-			while ( this.definitions[ canonicalName ] ) {
-				canonicalName = `_${canonicalName}`;
-			}
-
-			return canonicalName;
+			return deconflict( canonicalName, this.definitions );
 		}
 
 		if ( this.suggestedNames[ localName ] ) {
@@ -471,11 +474,7 @@ export default class Module {
 		// deconflict anonymous default exports with this module's definitions
 		const shouldDeconflict = this.exports.default && this.exports.default.isAnonymous;
 
-		if ( shouldDeconflict ) {
-			while ( suggestion in this.definitions ) {
-				suggestion = `_${suggestion}`;
-			}
-		}
+		if ( shouldDeconflict ) suggestion = deconflict( suggestion, this.definitions );
 
 		if ( !this.suggestedNames[ defaultOrBatch ] ) {
 			this.suggestedNames[ defaultOrBatch ] = makeLegalIdentifier( suggestion );
diff --git a/test/function/rename-default-export/_config.js b/test/function/rename-default-export/_config.js
new file mode 100644
index 0000000..24953e4
--- /dev/null
+++ b/test/function/rename-default-export/_config.js
@@ -0,0 +1,9 @@
+var assert = require( 'assert' );
+
+module.exports = {
+	description: 'avoids SyntaxError with default token (#33)',
+	exports: function ( exports ) {
+		assert.equal( exports.foo, 42 );
+		assert.equal( exports.bar, 42 );
+	}
+};
diff --git a/test/function/rename-default-export/bar.js b/test/function/rename-default-export/bar.js
new file mode 100644
index 0000000..c435404
--- /dev/null
+++ b/test/function/rename-default-export/bar.js
@@ -0,0 +1,3 @@
+import { baz } from './baz';
+
+export default baz;
diff --git a/test/function/rename-default-export/baz.js b/test/function/rename-default-export/baz.js
new file mode 100644
index 0000000..bc91852
--- /dev/null
+++ b/test/function/rename-default-export/baz.js
@@ -0,0 +1,5 @@
+function Baz () {}
+
+export var baz = 42;
+
+export default Baz( baz );
diff --git a/test/function/rename-default-export/foo.js b/test/function/rename-default-export/foo.js
new file mode 100644
index 0000000..c435404
--- /dev/null
+++ b/test/function/rename-default-export/foo.js
@@ -0,0 +1,3 @@
+import { baz } from './baz';
+
+export default baz;
diff --git a/test/function/rename-default-export/main.js b/test/function/rename-default-export/main.js
new file mode 100644
index 0000000..4725a8f
--- /dev/null
+++ b/test/function/rename-default-export/main.js
@@ -0,0 +1,7 @@
+import foo from './foo';
+import bar from './bar';
+
+export {
+	foo,
+	bar
+};