Merge pull request #920 from rollup/gh-919

allow empty for loop heads

package.json

@@ -61,7 +61,7 @@
     "mocha": "^3.0.0",
     "remap-istanbul": "^0.6.4",
     "require-relative": "^0.8.7",
-    "rollup": "^0.35.3",
+    "rollup": "^0.34.0",
     "rollup-plugin-buble": "^0.12.1",
     "rollup-plugin-commonjs": "^3.0.0",
     "rollup-plugin-json": "^2.0.0",

src/ast/Node.js

@@ -3,7 +3,7 @@ import getLocation from '../utils/getLocation.js';
 
 export default class Node {
 	bind ( scope ) {
-		this.eachChild( child => child.bind( scope ) );
+		this.eachChild( child => child.bind( this.scope || scope ) );
 	}
 
 	eachChild ( callback ) {
@@ -43,6 +43,8 @@ export default class Node {
 	}
 
 	hasEffects ( scope ) {
+		if ( this.scope ) scope = this.scope;
+
 		for ( const key of this.keys ) {
 			const value = this[ key ];
 
@@ -61,7 +63,7 @@ export default class Node {
 	}
 
 	initialise ( scope ) {
-		this.eachChild( child => child.initialise( scope ) );
+		this.eachChild( child => child.initialise( this.scope || scope ) );
 	}
 
 	locate () {
@@ -82,7 +84,7 @@ export default class Node {
 		this.ran = true;
 
 		this.eachChild( child => {
-			child.run( scope );
+			child.run( this.scope || scope );
 		});
 	}
 

src/ast/nodes/ArrowFunctionExpression.js

@@ -18,6 +18,7 @@ export default class ArrowFunctionExpression extends Node {
 	initialise ( scope ) {
 		if ( this.body.type === 'BlockStatement' ) {
 			this.body.createScope( scope );
+			this.scope = this.body.scope;
 		} else {
 			this.scope = new Scope({
 				parent: scope,
@@ -32,7 +33,6 @@ export default class ArrowFunctionExpression extends Node {
 			}
 		}
 
-		scope = this.scope || this.body.scope;
-		super.initialise( scope );
+		super.initialise( this.scope );
 	}
 }

src/ast/nodes/ForInStatement.js

@@ -1,11 +1,22 @@
 import Statement from './shared/Statement.js';
 import assignTo from './shared/assignTo.js';
+import Scope from '../scopes/Scope.js';
 import { STRING } from '../values.js';
 
 export default class ForInStatement extends Statement {
 	initialise ( scope ) {
+		if ( this.body.type === 'BlockStatement' ) {
 			this.body.createScope( scope );
-		super.initialise( this.body.scope );
-		assignTo( this.left, this.body.scope, STRING );
+			this.scope = this.body.scope;
+		} else {
+			this.scope = new Scope({
+				parent: scope,
+				isBlockScope: true,
+				isLexicalBoundary: false
+			});
+		}
+
+		super.initialise( this.scope );
+		assignTo( this.left, this.scope, STRING );
 	}
 }

src/ast/nodes/ForOfStatement.js

@@ -1,11 +1,22 @@
 import Statement from './shared/Statement.js';
 import assignTo from './shared/assignTo.js';
+import Scope from '../scopes/Scope.js';
 import { UNKNOWN } from '../values.js';
 
 export default class ForOfStatement extends Statement {
 	initialise ( scope ) {
+		if ( this.body.type === 'BlockStatement' ) {
 			this.body.createScope( scope );
-		super.initialise( this.body.scope );
-		assignTo( this.left, this.body.scope, UNKNOWN );
+			this.scope = this.body.scope;
+		} else {
+			this.scope = new Scope({
+				parent: scope,
+				isBlockScope: true,
+				isLexicalBoundary: false
+			});
+		}
+
+		super.initialise( this.scope );
+		assignTo( this.left, this.scope, UNKNOWN );
 	}
 }

src/ast/nodes/ForStatement.js

@@ -1,31 +1,23 @@
 import Statement from './shared/Statement.js';
+import Scope from '../scopes/Scope.js';
 
 export default class ForStatement extends Statement {
-	bind () {
-		const scope = this.body.scope;
-
-		this.init.bind( scope );
-		this.test.bind( scope );
-		this.update.bind( scope );
-		this.body.bind( scope );
-	}
-
-	hasEffects () {
-		return super.hasEffects( this.body.scope );
-	}
-
 	initialise ( scope ) {
+		if ( this.body.type === 'BlockStatement' ) {
 			this.body.createScope( scope );
-		scope = this.body.scope;
-
-		// can't use super, because we need to control the order
-		this.init.initialise( scope );
-		this.test.initialise( scope );
-		this.update.initialise( scope );
-		this.body.initialise( scope );
+			this.scope = this.body.scope;
+		} else {
+			this.scope = new Scope({
+				parent: scope,
+				isBlockScope: true,
+				isLexicalBoundary: false
+			});
 		}
 
-	run ( scope ) {
-		super.run( scope );
+		// can't use super, because we need to control the order
+		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.initialise( this.scope );
 	}
 }

test/form/body-less-for-loops/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'supports body-less for loops'
+};

test/form/body-less-for-loops/_expected/amd.js

@@ -0,0 +1,16 @@
+define(function () { 'use strict';
+
+	for ( let i = 0; i < 10; i += 1 ) console.log( i );
+	for ( const letter of array ) console.log( letter );
+	for ( const index in array ) console.log( index );
+
+	let i;
+	for ( i = 0; i < 10; i += 1 ) console.log( i );
+
+	let letter;
+	for ( letter of array ) console.log( letter );
+
+	let index;
+	for ( index in array ) console.log( index );
+
+});

test/form/body-less-for-loops/_expected/cjs.js

@@ -0,0 +1,14 @@
+'use strict';
+
+for ( let i = 0; i < 10; i += 1 ) console.log( i );
+for ( const letter of array ) console.log( letter );
+for ( const index in array ) console.log( index );
+
+let i;
+for ( i = 0; i < 10; i += 1 ) console.log( i );
+
+let letter;
+for ( letter of array ) console.log( letter );
+
+let index;
+for ( index in array ) console.log( index );

test/form/body-less-for-loops/_expected/es.js

@@ -0,0 +1,12 @@
+for ( let i = 0; i < 10; i += 1 ) console.log( i );
+for ( const letter of array ) console.log( letter );
+for ( const index in array ) console.log( index );
+
+let i;
+for ( i = 0; i < 10; i += 1 ) console.log( i );
+
+let letter;
+for ( letter of array ) console.log( letter );
+
+let index;
+for ( index in array ) console.log( index );

test/form/body-less-for-loops/_expected/iife.js

@@ -0,0 +1,17 @@
+(function () {
+	'use strict';
+
+	for ( let i = 0; i < 10; i += 1 ) console.log( i );
+	for ( const letter of array ) console.log( letter );
+	for ( const index in array ) console.log( index );
+
+	let i;
+	for ( i = 0; i < 10; i += 1 ) console.log( i );
+
+	let letter;
+	for ( letter of array ) console.log( letter );
+
+	let index;
+	for ( index in array ) console.log( index );
+
+}());

test/form/body-less-for-loops/_expected/umd.js

@@ -0,0 +1,20 @@
+(function (global, factory) {
+	typeof exports === 'object' && typeof module !== 'undefined' ? factory() :
+	typeof define === 'function' && define.amd ? define(factory) :
+	(factory());
+}(this, (function () { 'use strict';
+
+	for ( let i = 0; i < 10; i += 1 ) console.log( i );
+	for ( const letter of array ) console.log( letter );
+	for ( const index in array ) console.log( index );
+
+	let i;
+	for ( i = 0; i < 10; i += 1 ) console.log( i );
+
+	let letter;
+	for ( letter of array ) console.log( letter );
+
+	let index;
+	for ( index in array ) console.log( index );
+
+})));

test/form/body-less-for-loops/main.js

@@ -0,0 +1,12 @@
+for ( let i = 0; i < 10; i += 1 ) console.log( i );
+for ( const letter of array ) console.log( letter );
+for ( const index in array ) console.log( index );
+
+let i;
+for ( i = 0; i < 10; i += 1 ) console.log( i );
+
+let letter;
+for ( letter of array ) console.log( letter );
+
+let index;
+for ( index in array ) console.log( index );

test/form/for-loop-with-empty-head/_config.js

@@ -0,0 +1,3 @@
+module.exports = {
+	description: 'handles for loop with empty head'
+};

test/form/for-loop-with-empty-head/_expected/amd.js

@@ -0,0 +1,7 @@
+define(function () { 'use strict';
+
+	for ( ; ; ) {
+		console.log( 42 );
+	}
+
+});

test/form/for-loop-with-empty-head/_expected/cjs.js

@@ -0,0 +1,5 @@
+'use strict';
+
+for ( ; ; ) {
+	console.log( 42 );
+}

test/form/for-loop-with-empty-head/_expected/es.js

@@ -0,0 +1,3 @@
+for ( ; ; ) {
+	console.log( 42 );
+}

test/form/for-loop-with-empty-head/_expected/iife.js

@@ -0,0 +1,8 @@
+(function () {
+	'use strict';
+
+	for ( ; ; ) {
+		console.log( 42 );
+	}
+
+}());

test/form/for-loop-with-empty-head/_expected/umd.js

@@ -0,0 +1,11 @@
+(function (global, factory) {
+	typeof exports === 'object' && typeof module !== 'undefined' ? factory() :
+	typeof define === 'function' && define.amd ? define(factory) :
+	(factory());
+}(this, (function () { 'use strict';
+
+	for ( ; ; ) {
+		console.log( 42 );
+	}
+
+})));

test/form/for-loop-with-empty-head/main.js

@@ -0,0 +1,3 @@
+for ( ; ; ) {
+	console.log( 42 );
+}