ensure reference is only marked as reassignment if it is the subject of the reassignment – fixes #648

src/Statement.js

@@ -65,6 +65,8 @@ export default class Statement {
 
 				if ( parent && isModifierNode( parent ) ) {
 					let subject = parent[ modifierNodes[ parent.type ] ];
+
+					if ( node === subject ) {
 						let depth = 0;
 
 						while ( subject.type === 'MemberExpression' ) {
@@ -82,13 +84,14 @@ export default class Statement {
 							if ( depth < minDepth ) {
 								const err = new Error( `Illegal reassignment to import '${subject.name}'` );
 								err.file = module.id;
-							err.loc = getLocation( module.magicString.toString(), subject.start );
+								err.loc = getLocation( module.magicString.original, subject.start );
 								throw err;
 							}
 						}
 
 						isReassignment = !depth;
 					}
+				}
 
 				if ( isReference( node, parent ) ) {
 					// function declaration IDs are a special case – they're associated

test/function/export-two-ways-function/_config.js

@@ -0,0 +1,9 @@
+var assert = require( 'assert' );
+
+module.exports = {
+	description: 'exports the same function more than one way (#648)',
+	exports: function ( exports ) {
+		assert.equal( exports.foo, exports.bar );
+		assert.equal( exports.foo(), 42 );
+	}
+};

test/function/export-two-ways-function/main.js

@@ -0,0 +1,8 @@
+var bar;
+bar = foo;
+
+function foo () {
+	return 42;
+}
+
+export { foo, bar };