Merge pull request #1542 from rollup/gh-1538

init for loop scopes correctly

src/ast/nodes/ForOfStatement.js

@@ -6,7 +6,7 @@ import { UNKNOWN } from '../values.js';
 export default class ForOfStatement extends Statement {
 	initialiseChildren () {
 		this.left.initialise( this.scope );
-		this.right.initialise( this.scope );
+		this.right.initialise( this.scope.parent );
 		this.body.initialiseAndReplaceScope ?
 			this.body.initialiseAndReplaceScope( this.scope ) :
 			this.body.initialise( this.scope );

src/ast/nodes/ForStatement.js

@@ -6,9 +6,13 @@ export default class ForStatement extends Statement {
 		if ( this.init ) this.init.initialise( this.scope );
 		if ( this.test ) this.test.initialise( this.scope );
 		if ( this.update ) this.update.initialise( this.scope );
-		this.body.initialiseAndReplaceScope ?
-			this.body.initialiseAndReplaceScope( this.scope ) :
+
+		if ( this.body.type === 'BlockStatement' ) {
+			this.body.initialiseScope( this.scope );
+			this.body.initialiseChildren();
+		} else {
 			this.body.initialise( this.scope );
+		}
 	}
 
 	initialiseScope ( parentScope ) {

test/function/samples/for-in-loop-head-dependencies/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'uses parent scope for right-hand-side in for-in statement (#1480)'
+};

test/function/samples/for-in-loop-head-dependencies/main.js

@@ -0,0 +1,12 @@
+function foo() {
+	return ['x'];
+}
+
+const result = [];
+
+for (let i in foo()) {
+	const foo = i;
+	result.push(foo);
+}
+
+assert.deepEqual(result, [0]);

test/function/samples/for-loop-head-dependencies/_config.js

@@ -1,3 +1,3 @@
 module.exports = {
-	description: 'uses parent scope for right-hand-side in for-in statement (#1480)'
+	description: 'uses correct scope in for statement (#1538)'
 };

test/function/samples/for-loop-head-dependencies/main.js

@@ -1,12 +1,12 @@
 function foo() {
-	return ['x'];
+	return ['x', 'y'];
 }
 
 const result = [];
 
-for (let i in foo()) {
-	const foo = i;
+for (let a = foo(), i = 0; i < a.length; ++i) {
+	const foo = a[i];
 	result.push(foo);
 }
 
-assert.deepEqual(result, [0]);
+assert.deepEqual(result, ['x', 'y']);

test/function/samples/for-of-loop-head-dependencies/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'uses parent scope for right-hand-side in for-of statement (#1539)'
+};

test/function/samples/for-of-loop-head-dependencies/main.js

@@ -0,0 +1,12 @@
+function foo() {
+	return ['x', 'y'];
+}
+
+const result = [];
+
+for (const i of foo()) {
+	const foo = i;
+	result.push(i);
+}
+
+assert.deepEqual(result, ['x', 'y']);