feat(transpiler): class fields for Dart

gulpfile.js

@@ -25,6 +25,7 @@ var js2es5Options = {
   annotations: true, // parse annotations
   types: true, // parse types
   script: false, // parse as a module
+  memberVariables: true, // parse class fields
   modules: 'instantiate'
 };
 
@@ -42,6 +43,7 @@ var js2dartOptions = {
   annotations: true, // parse annotations
   types: true, // parse types
   script: false, // parse as a module
+  memberVariables: true, // parse class fields
   outputLanguage: 'dart'
 };
 

karma-dart.conf.js

@@ -60,6 +60,7 @@ module.exports = function(config) {
         sourceMaps: true,
         script: false,
         modules: 'register',
+        memberVariables: true,
         types: true,
         // typeAssertions: true,
         // typeAssertionModule: 'assert',

karma-js.conf.js

@@ -36,6 +36,7 @@ module.exports = function(config) {
         outputLanguage: 'es5',
         sourceMaps: true,
         script: false,
+        memberVariables: true,
         modules: 'instantiate',
         types: true,
         typeAssertions: true,

modules/test_lib/src/test_lib.dart

@@ -6,6 +6,8 @@ import 'package:unittest/unittest.dart' hide expect;
 import 'dart:mirrors';
 import 'dart:async';
 
+bool IS_DARTIUM = true;
+
 Expect expect(actual, [matcher]) {
   final expect = new Expect(actual);
   if (matcher != null) expect.to(matcher);

modules/test_lib/src/test_lib.es6

@@ -7,6 +7,7 @@ export var iit = window.iit;
 export var beforeEach = window.beforeEach;
 export var afterEach = window.afterEach;
 export var expect = window.expect;
+export var IS_DARTIUM = false;
 
 // To make testing consistent between dart and js
 window.print = function(msg) {

tools/transpiler/spec/classes_spec.js

@@ -49,6 +49,11 @@ class HasGetters {
   }
 }
 
+class WithFields {
+  name: string;
+  static id: number;
+}
+
 export function main() {
   describe('classes', function() {
     it('should work', function() {
@@ -89,6 +94,14 @@ export function main() {
         expect(HasGetters.staticGetter).toEqual('getter');
       });
     });
+
+    describe('fields', function() {
+      it('should work', function() {
+        var obj = new WithFields();
+        obj.name = 'Vojta';
+        WithFields.id = 12;
+      });
+    });
   });
 
 }

tools/transpiler/spec/types_spec.js

@@ -1,4 +1,4 @@
-import {describe, it, expect} from 'test_lib/test_lib';
+import {describe, it, expect, IS_DARTIUM} from 'test_lib/test_lib';
 
 class A {}
 class B {}
@@ -48,6 +48,12 @@ class Foo {
   }
 }
 
+class WithFields {
+  name: string;
+  static id: number;
+}
+
+
 export function main() {
   describe('types', function() {
     it('should work', function() {
@@ -58,5 +64,37 @@ export function main() {
 
       f.typedVariables();
     });
+
+    describe('class fields', function() {
+      it('should fail when setting wrong type value', function() {
+        var wf = new WithFields();
+
+        expect(function() {
+          wf.name = true;
+        }).toThrowError(IS_DARTIUM ?
+          // Dart
+          "type 'bool' is not a subtype of type 'String' of 'value'" :
+          // JavaScript
+          // TODO(vojta): Better error, it's not first argument, it's setting a field.
+          'Invalid arguments given!\n' +
+          '  - 1st argument has to be an instance of string, got true'
+        );
+      });
+    });
+
+    describe('static class fields', function() {
+      it('should fail when setting wrong type value', function() {
+        expect(function() {
+          WithFields.id = true;
+        }).toThrowError(IS_DARTIUM ?
+          // Dart
+          "type 'bool' is not a subtype of type 'num' of 'id'" :
+          // JavaScript
+          // TODO(vojta): Better error, it's not first argument, it's setting a field.
+          'Invalid arguments given!\n' +
+          '  - 1st argument has to be an instance of number, got true'
+        );
+      });
+    });
   });
 }

tools/transpiler/src/outputgeneration/DartParseTreeWriter.js

@@ -32,6 +32,19 @@ export class DartParseTreeWriter extends JavaScriptParseTreeWriter {
     this.libName = moduleName.replace(/\//g, '.').replace(/[^\w.\/]/g, '_');
   }
 
+  // CLASS FIELDS
+  visitPropertyVariableDeclaration(tree) {
+    if (tree.isStatic) {
+      this.write_(STATIC);
+      this.writeSpace_();
+    }
+
+    this.writeType_(tree.typeAnnotation);
+    this.writeSpace_();
+    this.visitAny(tree.name);
+    this.write_(SEMI_COLON);
+  }
+
   // VARIABLES - types
   // ```
   // var foo:bool = true;