Support user generated custom native JS classes.

tests/html/js_array_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-library jsArrayTest;
+@Js("ArrayTest.Util")
+library js_array_test;
 
 import 'dart:html';
-import 'dart:js';
 
+import 'dart:js' as js;
+import 'package:js/js.dart';
 import 'package:unittest/unittest.dart';
 import 'package:unittest/html_config.dart';
+import 'json_helper.dart' as json_helper;
 
 _injectJs() {
   document.body.append(new ScriptElement()
     ..type = 'text/javascript'
     ..innerHtml = r"""
-function callJsMethod(jsObj, jsMethodName, args) {
-  return jsObj[jsMethodName].apply(jsObj, args);
+ArrayTest = {};
+ArrayTest.Util = {
+  callJsMethod: function(jsObj, jsMethodName, args) {
+    return jsObj[jsMethodName].apply(jsObj, args);
+  },
+
+  jsEnumerateIndices: function(obj) {
+    var ret = [];
+    for(var i in obj) {
+      ret.push(i);
+    }
+    return ret;
+  },
+
+  checkIsArray: function(obj) {
+    return Array.isArray(obj);
+  },
+
+  concatValues: function(obj) {
+    return obj.concat("a", "b", ["c", "d"], 42, {foo: 10});
+  },
+
+  concatOntoArray: function(obj) {
+    return [1,2,3].concat(obj, "foo");
+  },
+
+  repeatedConcatOntoArray: function(obj) {
+    return [1,2,3].concat(obj, obj);
+  },
+
+  everyGreaterThanZero: function(obj) {
+    return obj.every(function(currentValue, index, array) {
+      return currentValue > 0;
+    });
+  },
+
+  everyGreaterThanZeroCheckThisArg: function(obj) {
+    var j = 0;
+    return obj.every(function(currentValue, index, array) {
+      if (j != index) {
+        throw "Unxpected index";
+      }
+      j++;
+      if (array !== obj) {
+        throw "Array argument doesn't match obj";
+      }
+      return currentValue > 0;
+    });
+  },
+
+  filterGreater42: function(obj) {
+    return obj.filter(function(currentValue, index, array) {
+      return currentValue > 42;
+    });
+  },
+
+  forEachCollectResult: function(array) {
+    var result = [];
+    array.forEach(function(currentValue) {
+      result.push(currentValue * 2);
+    });
+    return result;
+  },
+
+  someEqual42: function(array) {
+    return array.some(function(currentValue) {
+      return currentValue == 42;
+    });
+  },
+
+  sortNumbersBackwards: function(array) {
+    return array.sort(function(a, b) {
+      return b - a;
+    });
+  },
+
+  spliceDummyItems: function(array) {
+    return array.splice(1, 2, "quick" ,"brown", "fox");
+  },
+
+  spliceTestStringArgs: function(array) {
+    return array.splice("1.2", "2.01", "quick" ,"brown", "fox");
+  },
+
+  splicePastEnd: function(array) {
+    return array.splice(1, 5332, "quick" ,"brown", "fox");
+  },
+
+  callJsToString: function(array) {
+    return array.toString();
+  },
+
+  mapAddIndexToEachElement: function(array) {
+    return array.map(function(currentValue, index) {
+      return currentValue + index;
+    });
+  },
+
+  reduceSumDoubledElements: function(array) {
+    return array.reduce(function(previousValue, currentValue) {
+          return previousValue + currentValue*2;
+        },
+        0);
+  },
+
+  // TODO(jacobr): add a test that distinguishes reduce from reduceRight.
+  reduceRightSumDoubledElements: function(array) {
+    return array.reduceRight(function(previousValue, currentValue) {
+          return previousValue + currentValue*2;
+        },
+        0);
+  },
+
+  getOwnPropertyDescriptorJson: function(array, property) {
+    return JSON.stringify(Object.getOwnPropertyDescriptor(array, property));
+  },
+
+  setLength: function(array, len) {
+    return array.length = len;
+  },
+
+  getValue: function(obj, index) {
+    return obj[index];
+  },
+
+  setValue: function(obj, index, value) {
+    return obj[index] = value;
+  },
+
+  // Calling a method from Dart List on an arbitrary target object.
+  callListMethodOnTarget: function(dartArray, target, methodName, args) {
+    return dartArray[methodName].apply(target, args);
+  },
+
+  newArray: function() { return []; },
+
+  newLiteral: function() { return {}; },
+
+};
+""");
 }
 
-function jsEnumerateIndices(obj) {
-  var ret = [];
-  for(var i in obj) {
-    ret.push(i);
-  }
-  return ret;
-}
-
-function setValue(obj, index, value) {
-  return obj[index] = value;
-}
-
-function getValue(obj, index) {
-  return obj[index];
-}
-
-function checkIsArray(obj) {
-  return Array.isArray(obj);
-}
-
-function concatValues(obj) {
-  return obj.concat("a", "b", ["c", "d"], 42, {foo: 10});
-}
-
-function concatOntoArray(obj) {
-  return [1,2,3].concat(obj, "foo");
-}
-
-function repeatedConcatOntoArray(obj) {
-  return [1,2,3].concat(obj, obj);
-}
-
-function everyGreaterThanZero(obj) {
-  return obj.every(function(currentValue, index, array) {
-    return currentValue > 0;
-  });
-}
-
-function everyGreaterThanZeroCheckThisArg(obj) {
-  var j = 0;
-  return obj.every(function(currentValue, index, array) {
-    if (j != index) {
-      throw "Unxpected index";
-    }
-    j++;
-    if (array !== obj) {
-      throw "Array argument doesn't match obj";
-    }
-    return currentValue > 0;
-  });
-}
-
-function filterGreater42(obj) {
-  return obj.filter(function(currentValue, index, array) {
-    return currentValue > 42;
-  });
-}
-
-function forEachCollectResult(array, callback) {
-  var result = [];
-  array.forEach(function(currentValue) {
-    result.push(currentValue * 2);
-  });
-  return result;
-}
-
-function someEqual42(array, callback) {
-  return array.some(function(currentValue) {
-    return currentValue == 42;
-  });
-}
-
-function sortNumbersBackwards(array) {
-  return array.sort(function(a, b) {
-    return b - a;
-  });
-}
-
-function spliceDummyItems(array) {
-  return array.splice(1, 2, "quick" ,"brown", "fox");
-}
-
-function spliceTestStringArgs(array) {
-  return array.splice("1.2", "2.01", "quick" ,"brown", "fox");
-}
-
-function splicePastEnd(array) {
-  return array.splice(1, 5332, "quick" ,"brown", "fox");
-}
-
-function callJsToString(array) {
-  return array.toString();
-}
-
-function mapAddIndexToEachElement(array) {
-  return array.map(function(currentValue, index) {
-    return currentValue + index;
-  });
-}
-
-function reduceSumDoubledElements(array) {
-  return array.reduce(function(previousValue, currentValue) {
-        return previousValue + currentValue*2;
-      },
-      0);
-}
-
-// TODO(jacobr): add a test that distinguishes reduce from reduceRight.
-function reduceRightSumDoubledElements(array) {
-  return array.reduceRight(function(previousValue, currentValue) {
-        return previousValue + currentValue*2;
-      },
-      0);
-}
-
-function identical(o1, o2) {
-  return o1 === o2;
-}
-
-function getOwnPropertyDescriptorJson(array, property) {
-  return JSON.stringify(Object.getOwnPropertyDescriptor(array, property));
-}
-
-function setLength(array, len) {
-  return array.length = len;
-}
-
-function jsonStringify(o) {
-  return JSON.stringify(o);
-}
-
-// Calling a method from Dart List on an arbitrary target object.
-function callListMethodOnTarget(dartArray, target, methodName, args) {
-  return dartArray[methodName].apply(target, args);
-}
-
-""");
+@Js()
+class SimpleJsLiteralClass {
+  external get foo;
 }
 
 class Foo {}
 
-callJsMethod(List array, String methodName, List args) =>
-    context.callMethod("callJsMethod", [array, methodName, args]);
+@Js()
+external callJsMethod(List array, String methodName, List args);
 
 callIndexOf(List array, value) => callJsMethod(array, "indexOf", [value]);
 callLastIndexOf(List array, value) =>
     callJsMethod(array, "lastIndexOf", [value]);
 
 callPop(List array) => callJsMethod(array, "pop", []);
 callPush(List array, element) => callJsMethod(array, "push", [element]);
 callShift(List array) => callJsMethod(array, "shift", []);
 callReverse(List array) => callJsMethod(array, "reverse", []);
-callSetLength(List array, length) =>
-    context.callMethod("setLength", [array, length]);
 
-callListMethodOnObject(JsObject object, String methodName, List args) => context
-    .callMethod("callListMethodOnTarget", [[], object, methodName, args]);
+callListMethodOnObject(object, String methodName, List args) =>
+    callListMethodOnTarget([], object, methodName, args);
 
-jsonStringify(JsObject object) => context.callMethod("jsonStringify", [object]);
+@Js()
+external jsEnumerateIndices(obj);
+@Js()
+external bool checkIsArray(obj);
+@Js()
+external concatValues(obj);
+
+@Js()
+external concatOntoArray(obj);
+
+@Js()
+external repeatedConcatOntoArray(obj);
+@Js()
+external bool everyGreaterThanZero(obj);
+@Js()
+external bool everyGreaterThanZeroCheckThisArg(obj);
+
+@Js()
+external filterGreater42(obj);
+
+@Js()
+external forEachCollectResult(List array);
+@Js()
+external someEqual42(List array);
+@Js()
+external sortNumbersBackwards(List array);
+
+@Js()
+external List spliceDummyItems(List array);
+
+@Js()
+external List spliceTestStringArgs(List array);
+
+@Js()
+external List splicePastEnd(List array);
+
+@Js()
+external String callJsToString(List array);
+
+@Js()
+external mapAddIndexToEachElement(List array);
+@Js()
+external reduceSumDoubledElements(List array);
+
+// TODO(jacobr): add a test that distinguishes reduce from reduceRight.
+@Js()
+external reduceRightSumDoubledElements(List array);
+
+@Js()
+external getOwnPropertyDescriptorJson(List array, property);
+
+@Js("setLength")
+external callSetLength(List array, length);
+
+@Js()
+external getValue(obj, index);
+
+@Js()
+external setValue(obj, index, value);
+
+@Js()
+external callListMethodOnTarget(List target, object, String methodName, List args);
+
+@Js()
+external newArray();
+
+@Js()
+external newLiteral();
 
 main() {
   _injectJs();
   useHtmlConfiguration();
 
   group('indexOf', () {
     var div = new DivElement();
     var list = [3, 42, "foo", 42, div];
     test('found', () {
       expect(callIndexOf(list, 3), equals(0));
@@ skipping 41 matching lines @@
       expect(list.length, equals(2));
     });
   });
 
   group('join', () {
     var list = [3, 42, "foo"];
     var listWithDartClasses = [3, new Foo(), 42, "foo", new Object()];
     test('default', () {
       expect(callJsMethod(list, "join", []), equals("3,42,foo"));
       expect(callJsMethod(listWithDartClasses, "join", []),
-          equals("3,Instance of 'Foo',42,foo,Instance of 'Object'"));
+          equals("3,${new Foo()},42,foo,${new Object()}"));
     });
 
     test('custom separator', () {
       expect(callJsMethod(list, "join", ["##"]), equals("3##42##foo"));
     });
   });
 
   group('lastIndexOf', () {
     var list = [3, 42, "foo", 42];
     test('found', () {
@@ skipping 116 matching lines @@
       expect(callJsMethod(list, "slice", [-2, 3]), equals([92]));
 
       // Past the end of the front of the array.
       expect(callJsMethod(list, "slice", [-10, 2]), equals([3, 42]));
     });
   });
 
   group("js snippet tests", () {
     test("enumerate indices", () {
       var list = ["a", "b", "c", "d"];
-      var indices = context.callMethod('jsEnumerateIndices', [list]);
+      var indices =
+          jsEnumerateIndices(list);
       expect(indices.length, equals(4));
       for (int i = 0; i < 4; i++) {
         expect(indices[i], equals('$i'));
       }
     });
 
     test("set element", () {
       var list = ["a", "b", "c", "d"];
-      context.callMethod('setValue', [list, 0, 42]);
+      setValue(list, 0, 42);
       expect(list[0], equals(42));
-      context.callMethod('setValue', [list, 1, 84]);
+      setValue(list, 1, 84);
       expect(list[1], equals(84));
-      context.callMethod(
-          'setValue', [list, 6, 100]); // Off the end of the list.
+      setValue(list, 6, 100); // Off the end of the list.
       expect(list.length, equals(7));
       expect(list[4], equals(null));
       expect(list[6], equals(100));
 
       // These tests have to be commented out because we don't persist
       // JS proxies for Dart objects like we could/should.
-      // context.callMethod('setValue', [list, -1, "foo"]); // Not a valid array index
-      // expect(context.callMethod('getValue', [list, -1]), equals("foo"));
-      // expect(context.callMethod('getValue', [list, "-1"]), equals("foo"));
+      // setValue(list, -1, "foo"); // Not a valid array index
+      // expect(getValue(list, -1), equals("foo"));
+      // expect(getValue(list, "-1"), equals("foo"));
     });
 
     test("get element", () {
       var list = ["a", "b", "c", "d"];
-      expect(context.callMethod('getValue', [list, 0]), equals("a"));
-      expect(context.callMethod('getValue', [list, 1]), equals("b"));
-      expect(context.callMethod('getValue', [list, 6]), equals(null));
-      expect(context.callMethod('getValue', [list, -1]), equals(null));
+      expect(getValue(list, 0),
+          equals("a"));
+      expect(getValue(list, 1),
+          equals("b"));
+      expect(getValue(list, 6),
+          equals(null));
+      expect(getValue(list, -1),
+          equals(null));
 
-      expect(context.callMethod('getValue', [list, "0"]), equals("a"));
-      expect(context.callMethod('getValue', [list, "1"]), equals("b"));
+      expect(getValue(list, "0"),
+          equals("a"));
+      expect(getValue(list, "1"),
+          equals("b"));
     });
 
     test("is array", () {
       var list = ["a", "b"];
-      expect(context.callMethod("checkIsArray", [list]), isTrue);
+      expect(checkIsArray(list), isTrue);
     });
 
     test("property descriptors", () {
       // This test matters to make behavior consistent with JS native arrays
       // and to make devtools integration work well.
       var list = ["a", "b"];
-      expect(context.callMethod("getOwnPropertyDescriptorJson", [list, 0]),
+      expect(getOwnPropertyDescriptorJson(list, 0),
           equals('{"value":"a",'
               '"writable":true,'
               '"enumerable":true,'
               '"configurable":true}'));
 
       expect(
-          context.callMethod("getOwnPropertyDescriptorJson", [list, "length"]),
+          getOwnPropertyDescriptorJson(list, "length"),
           equals('{"value":2,'
               '"writable":true,'
               '"enumerable":false,'
               '"configurable":false}'));
     });
 
     test("concat js arrays", () {
       var list = ["1", "2"];
       // Tests that calling the concat method from JS will flatten out JS arrays
       // We concat the array with "a", "b", ["c", "d"], 42, {foo: 10}
       // which should generate ["1", "2", "a", "b", ["c", "d"], 42, {foo: 10}]
-      var ret = context.callMethod("concatValues", [list]);
+      var ret = concatValues(list);
       expect(list.length, equals(2));
       expect(ret.length, equals(8));
       expect(ret[0], equals("1"));
       expect(ret[3], equals("b"));
       expect(ret[5], equals("d"));
       expect(ret[6], equals(42));
-      expect(ret[7]['foo'], equals(10));
+      SimpleJsLiteralClass item = ret[7];
+      expect(item.foo, equals(10));
     });
 
     test("concat onto arrays", () {
       // This test only passes if we have monkey patched the core Array object
       // prototype to handle Dart Lists.
       var list = ["a", "b"];
-      var ret = context.callMethod("concatOntoArray", [list]);
+      var ret = concatOntoArray(list);
       expect(list.length, equals(2));
       expect(ret, equals([1, 2, 3, "a", "b", "foo"]));
     });
 
     test("dart arrays on dart arrays", () {
       // This test only passes if we have monkey patched the core Array object
       // prototype to handle Dart Lists.
       var list = ["a", "b"];
-      var ret = callJsMethod(list, "concat", [["c", "d"], "e", ["f", "g"]]);
+      var ret = callJsMethod(list, "concat", [
+        ["c", "d"],
+        "e",
+        ["f", "g"]
+      ]);
       expect(list.length, equals(2));
       expect(ret, equals(["a", "b", "c", "d", "e", "f", "g"]));
     });
 
     test("every greater than zero", () {
-      expect(context.callMethod("everyGreaterThanZero", [[1, 5]]), isTrue);
-      expect(context.callMethod("everyGreaterThanZeroCheckThisArg", [[1, 5]]),
+      expect(
+          everyGreaterThanZero([1, 5]),
           isTrue);
-      expect(context.callMethod("everyGreaterThanZero", [[1, 0]]), isFalse);
-      expect(context.callMethod("everyGreaterThanZero", [[]]), isTrue);
+      expect(
+          everyGreaterThanZeroCheckThisArg([1, 5]),
+          isTrue);
+      expect(
+          everyGreaterThanZero([1, 0]),
+          isFalse);
+      expect(everyGreaterThanZero([]),
+          isTrue);
     });
 
     test("filter greater than 42", () {
-      expect(context.callMethod("filterGreater42", [[1, 5]]), equals([]));
-      expect(context.callMethod("filterGreater42", [[43, 5, 49]]),
+      expect(filterGreater42([1, 5]), equals([]));
+      expect(
+          filterGreater42([43, 5, 49]),
           equals([43, 49]));
-      expect(context.callMethod("filterGreater42", [["43", "5", "49"]]),
+      expect(
+          filterGreater42(["43", "5", "49"]),
           equals(["43", "49"]));
     });
 
     test("for each collect result", () {
-      expect(context.callMethod("forEachCollectResult", [[1, 5, 7]]),
+      expect(
+          forEachCollectResult([1, 5, 7]),
           equals([2, 10, 14]));
     });
 
     test("some", () {
-      expect(context.callMethod("someEqual42", [[1, 5, 9]]), isFalse);
-      expect(context.callMethod("someEqual42", [[1, 42, 9]]), isTrue);
+      expect(someEqual42([1, 5, 9]),
+          isFalse);
+      expect(someEqual42([1, 42, 9]),
+          isTrue);
     });
 
     test("sort backwards", () {
       var arr = [1, 5, 9];
-      var ret = context.callMethod("sortNumbersBackwards", [arr]);
+      var ret = sortNumbersBackwards(arr);
       expect(identical(arr, ret), isTrue);
       expect(ret, equals([9, 5, 1]));
     });
 
     test("splice dummy items", () {
       var list = [1, 2, 3, 4];
-      var removed = context.callMethod("spliceDummyItems", [list]);
+      var removed = spliceDummyItems(list);
       expect(removed.length, equals(2));
       expect(removed[0], equals(2));
       expect(removed[1], equals(3));
       expect(list.first, equals(1));
       expect(list[1], equals("quick"));
       expect(list[2], equals("brown"));
       expect(list[3], equals("fox"));
       expect(list.last, equals(4));
     });
 
     test("splice string args", () {
       var list = [1, 2, 3, 4];
-      var removed = context.callMethod("spliceTestStringArgs", [list]);
+      var removed = spliceTestStringArgs(list);
       expect(removed.length, equals(2));
       expect(removed[0], equals(2));
       expect(removed[1], equals(3));
       expect(list.first, equals(1));
       expect(list[1], equals("quick"));
       expect(list[2], equals("brown"));
       expect(list[3], equals("fox"));
       expect(list.last, equals(4));
     });
 
     test("splice pastEndOfArray", () {
       var list = [1, 2, 3, 4];
-      var removed = context.callMethod("splicePastEnd", [list]);
+      var removed = splicePastEnd(list);
       expect(removed.length, equals(3));
       expect(list.first, equals(1));
       expect(list.length, equals(4));
       expect(list[1], equals("quick"));
       expect(list[2], equals("brown"));
       expect(list[3], equals("fox"));
     });
 
     test("splice both bounds past end of array", () {
       var list = [1];
-      var removed = context.callMethod("splicePastEnd", [list]);
+      var removed = splicePastEnd(list);
       expect(removed.length, equals(0));
       expect(list.first, equals(1));
       expect(list.length, equals(4));
       expect(list[1], equals("quick"));
       expect(list[2], equals("brown"));
       expect(list[3], equals("fox"));
     });
 
     test("call List method on JavaScript object", () {
-      var jsObject = new JsObject.jsify({});
+      var jsObject = newLiteral();
       callListMethodOnObject(jsObject, 'push', ["a"]);
       callListMethodOnObject(jsObject, 'push', ["b"]);
       callListMethodOnObject(jsObject, 'push', ["c", "d"]);
       callListMethodOnObject(jsObject, 'push', []);
 
-      expect(jsonStringify(jsObject),
+      expect(json_helper.stringify(jsObject),
           equals('{"0":"a","1":"b","2":"c","3":"d","length":4}'));
 
       expect(callListMethodOnObject(jsObject, 'pop', []), equals("d"));
       expect(callListMethodOnObject(jsObject, 'join', ["#"]), equals("a#b#c"));
 
-      var jsArray = new JsObject.jsify([]);
+      var jsArray = newArray();
       callListMethodOnObject(jsArray, 'push', ["a"]);
       callListMethodOnObject(jsArray, 'push', ["b"]);
       callListMethodOnObject(jsArray, 'push', ["c", "d"]);
       callListMethodOnObject(jsArray, 'push', []);
 
-      expect(jsonStringify(jsArray), equals('["a","b","c","d"]'));
+      expect(json_helper.stringify(jsArray), equals('["a","b","c","d"]'));
     });
   });
 
   // This test group is disabled until we figure out an efficient way to
   // distinguish between "array" Dart List types and non-array Dart list types.
   /*
   group('Non-array Lists', () {
     test('opaque proxy', () {
       // Dartium could easily support making LinkedList and all other classes
       // implementing List behave like a JavaScript array but that would
       // be challenging to implement in dart2js until browsers support ES6.
       var list = ["a", "b", "c", "d"];
       var listView = new UnmodifiableListView(list.getRange(1,3));
       expect(listView is List, isTrue);
       expect(listView.length, equals(2));
-      expect(context.callMethod("checkIsArray", [listView]), isFalse);
-      expect(context.callMethod("checkIsArray", [listView.toList()]), isTrue);
-      expect(context.callMethod("getOwnPropertyDescriptorJson",
-          [listView, "length"]), equals("null"));
+      expect(checkIsArray(listView), isFalse);
+      expect(checkIsArray(listView.toList()), isTrue);
+      expect(getOwnPropertyDescriptorJson(
+          listView, "length"), equals("null"));
     });
   });
   */
 }