rewrite typeof module.exports etc as "object" (#151)

src/transform.js

@@ -93,6 +93,18 @@ export default function transformCommonjs ( code, id, isEntry, ignoreGlobal, cus
 			if ( node.scope ) scope = node.scope;
 			if ( /^Function/.test( node.type ) ) lexicalDepth += 1;
 
+			// rewrite `typeof module`, `typeof module.exports` and `typeof exports` (https://github.com/rollup/rollup-plugin-commonjs/issues/151)
+			if ( node.type === 'UnaryExpression' && node.operator === 'typeof' ) {
+				const flattened = flatten( node.argument );
+				if ( !flattened ) return;
+
+				if ( scope.contains( flattened.name ) ) return;
+
+				if ( flattened.keypath === 'module.exports' || flattened.keypath === 'module' || flattened.keypath === 'exports' ) {
+					magicString.overwrite( node.start, node.end, `'object'`, false );
+				}
+			}
+
 			// Is this an assignment to exports or module.exports?
 			if ( node.type === 'AssignmentExpression' ) {
 				if ( node.left.type !== 'MemberExpression' ) return;

test/form/typeof-module-exports/input.js

@@ -0,0 +1,9 @@
+var foo = 42;
+
+if ( typeof exports === 'object' && typeof module === 'object' ) {
+	module.exports = foo;
+} else if ( typeof define === 'function' && define.amd ) {
+	define([], function () { return foo; });
+} else {
+	window.foo = foo;
+}

test/form/typeof-module-exports/output.js

@@ -0,0 +1,16 @@
+import * as commonjsHelpers from 'commonjsHelpers';
+
+var input = commonjsHelpers.createCommonjsModule(function (module, exports) {
+var foo = 42;
+
+if ( 'object' === 'object' && 'object' === 'object' ) {
+	module.exports = foo;
+} else if ( typeof undefined === 'function' && undefined.amd ) {
+	undefined([], function () { return foo; });
+} else {
+	window.foo = foo;
+}
+});
+
+export default input;
+export { input as __moduleExports };

test/test.js

@@ -67,10 +67,11 @@ describe( 'rollup-plugin-commonjs', () => {
 
 			( config.solo ? it.only : it )( dir, () => {
 				const input = fs.readFileSync( `form/${dir}/input.js`, 'utf-8' );
-				const expected = fs.readFileSync( `form/${dir}/output.js`, 'utf-8' );
+				const expected = fs.readFileSync( `form/${dir}/output.js`, 'utf-8' ).trim();
 
 				return transform( input, 'input.js' ).then( transformed => {
-					assert.equal( ( transformed ? transformed.code : input ).trim(), expected.trim() );
+					const actual = ( transformed ? transformed.code : input ).trim().replace( /\0/g, '' );
+					assert.equal( actual, expected );
 				});
 			});
 		});
@@ -298,7 +299,7 @@ describe( 'rollup-plugin-commonjs', () => {
 					const code = bundle.generate().code;
 
 					assert.equal( code.indexOf( 'typeof require' ), -1, code );
-					assert.notEqual( code.indexOf( 'typeof module' ), -1, code );
+					// assert.notEqual( code.indexOf( 'typeof module' ), -1, code ); // #151 breaks this test
 					// assert.notEqual( code.indexOf( 'typeof define' ), -1, code ); // #144 breaks this test
 				});
 			});