fix #603, support mock objects

if noSuchMethod is used to implement an abstract member, this will be detected and appropriate code will be generated.

R=leafp@google.com

Review URL: https://codereview.chromium.org/2158173003 .

Author: John Messerly

pkg/dev_compiler/lib/runtime/dart_sdk.js

@@ -40,7 +40,6 @@ dart_library.library('dart_sdk', null, /* Imports */[
   let JSArrayOfFormatter = () => (JSArrayOfFormatter = dart.constFn(_interceptors.JSArray$(_debugger.Formatter)))();
   let LinkedHashSetOfNameValuePair = () => (LinkedHashSetOfNameValuePair = dart.constFn(collection.LinkedHashSet$(_debugger.NameValuePair)))();
   let SetOfString = () => (SetOfString = dart.constFn(core.Set$(core.String)))();
-  let IterableOfNameValuePair = () => (IterableOfNameValuePair = dart.constFn(core.Iterable$(_debugger.NameValuePair)))();
   let ListOfNameValuePair = () => (ListOfNameValuePair = dart.constFn(core.List$(_debugger.NameValuePair)))();
   let JSArrayOfJsonMLFormatter = () => (JSArrayOfJsonMLFormatter = dart.constFn(_interceptors.JSArray$(_debugger.JsonMLFormatter)))();
   let JSArray = () => (JSArray = dart.constFn(_interceptors.JSArray$()))();
@@ -482,7 +481,7 @@ dart_library.library('dart_sdk', null, /* Imports */[
   let dynamicToList = () => (dynamicToList = dart.constFn(dart.definiteFunctionType(core.List, [dart.dynamic])))();
   let TypeToString = () => (TypeToString = dart.constFn(dart.definiteFunctionType(core.String, [core.Type])))();
   let dynamicAndStringTobool = () => (dynamicAndStringTobool = dart.constFn(dart.definiteFunctionType(core.bool, [dart.dynamic, core.String])))();
-  let dynamicAnddynamicTodynamic$ = () => (dynamicAnddynamicTodynamic$ = dart.constFn(dart.definiteFunctionType(dart.dynamic, [dart.dynamic, dart.dynamic])))();
+  let intAnddynamicTovoid = () => (intAnddynamicTovoid = dart.constFn(dart.definiteFunctionType(dart.void, [core.int, dart.dynamic])))();
   let dynamicTobool$ = () => (dynamicTobool$ = dart.constFn(dart.definiteFunctionType(core.bool, [dart.dynamic])))();
   let dynamicAnddynamicTovoid = () => (dynamicAnddynamicTovoid = dart.constFn(dart.definiteFunctionType(dart.void, [dart.dynamic, dart.dynamic])))();
   let VoidTodynamic$ = () => (VoidTodynamic$ = dart.constFn(dart.definiteFunctionType(dart.dynamic, [])))();
@@ -498,6 +497,7 @@ dart_library.library('dart_sdk', null, /* Imports */[
   let FunctionTovoid = () => (FunctionTovoid = dart.constFn(dart.definiteFunctionType(dart.void, [core.Function])))();
   let StringAndStringToString = () => (StringAndStringToString = dart.constFn(dart.definiteFunctionType(core.String, [core.String, core.String])))();
   let TypeAndStringTodynamic = () => (TypeAndStringTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [core.Type, core.String])))();
+  let dynamicAnddynamicTodynamic$ = () => (dynamicAnddynamicTodynamic$ = dart.constFn(dart.definiteFunctionType(dart.dynamic, [dart.dynamic, dart.dynamic])))();
   let ListOfEToListOfE = () => (ListOfEToListOfE = dart.constFn(dart.definiteFunctionType(E => [core.List$(E), [core.List$(E)]])))();
   let StringTovoid = () => (StringTovoid = dart.constFn(dart.definiteFunctionType(dart.void, [core.String])))();
   let _IsolateContextAndFunctionTodynamic = () => (_IsolateContextAndFunctionTodynamic = dart.constFn(dart.definiteFunctionType(dart.dynamic, [_isolate_helper._IsolateContext, core.Function])))();
@@ -1318,15 +1318,15 @@ dart_library.library('dart_sdk', null, /* Imports */[
       if (dart.test(dart.hasMethod(obj, f))) return dart.bind(obj, f, void 0);
       return obj[f];
     }
-    return dart.noSuchMethod(obj, new dart._Invocation(core.String._check(field), [], {isGetter: true}));
+    return dart.noSuchMethod(obj, new dart.InvocationImpl(core.String._check(field), [], {isGetter: true}));
   };
   dart.dput = function(obj, field, value) {
     let f = dart._canonicalMember(obj, field);
     dart._trackCall(obj, f);
     if (f != null) {
       return obj[f] = value;
     }
-    return dart.noSuchMethod(obj, new dart._Invocation(core.String._check(field), [value], {isSetter: true}));
+    return dart.noSuchMethod(obj, new dart.InvocationImpl(core.String._check(field), [value], {isSetter: true}));
   };
   dart._checkApply = function(type, actuals) {
     if (actuals.length < type.args.length) return false;
@@ -1368,7 +1368,7 @@ dart_library.library('dart_sdk', null, /* Imports */[
       if (args.length > 0 && args[args.length - 1].__proto__ == Object.prototype) {
         namedArgs = args.pop();
       }
-      return dart.noSuchMethod(originalTarget, new dart._Invocation(name, args, {namedArguments: namedArgs, isMethod: true}));
+      return dart.noSuchMethod(originalTarget, new dart.InvocationImpl(name, args, {namedArguments: namedArgs, isMethod: true}));
     }
     if (!(f instanceof Function)) {
       if (f != null) {
@@ -1449,7 +1449,7 @@ dart_library.library('dart_sdk', null, /* Imports */[
   dart._callMethod = function(obj, name, typeArgs, args, displayName) {
     let symbol = dart._canonicalMember(obj, name);
     if (symbol == null) {
-      return dart.noSuchMethod(obj, new dart._Invocation(core.String._check(displayName), core.List._check(args), {isMethod: true}));
+      return dart.noSuchMethod(obj, new dart.InvocationImpl(core.String._check(displayName), core.List._check(args), {isMethod: true}));
     }
     let f = obj != null ? obj[symbol] : null;
     let ftype = dart.getMethodType(obj, symbol);
@@ -2249,7 +2249,7 @@ dart_library.library('dart_sdk', null, /* Imports */[
       return dart.test(this.isGetter) || dart.test(this.isSetter);
     }
   };
-  dart._Invocation = class _Invocation extends core.Invocation {
+  dart.InvocationImpl = class InvocationImpl extends core.Invocation {
     new(memberName, positionalArguments, opts) {
       let namedArguments = opts && 'namedArguments' in opts ? opts.namedArguments : null;
       let isMethod = opts && 'isMethod' in opts ? opts.isMethod : false;
@@ -2260,15 +2260,15 @@ dart_library.library('dart_sdk', null, /* Imports */[
       this.isGetter = isGetter;
       this.isSetter = isSetter;
       this.memberName = dart._dartSymbol(memberName);
-      this.namedArguments = dart._Invocation._namedArgsToSymbols(namedArguments);
+      this.namedArguments = dart.InvocationImpl._namedArgsToSymbols(namedArguments);
     }
     static _namedArgsToSymbols(namedArgs) {
       if (namedArgs == null) return dart.map();
       return MapOfSymbol$dynamic().fromIterable(dart.getOwnPropertyNames(namedArgs), {key: dart._dartSymbol, value: dart.fn(k => namedArgs[k], dynamicTodynamic$())});
     }
   };
-  dart.setSignature(dart._Invocation, {
-    constructors: () => ({new: dart.definiteFunctionType(dart._Invocation, [core.String, core.List], {namedArguments: dart.dynamic, isMethod: core.bool, isGetter: core.bool, isSetter: core.bool})}),
+  dart.setSignature(dart.InvocationImpl, {
+    constructors: () => ({new: dart.definiteFunctionType(dart.InvocationImpl, [core.String, core.List], {namedArguments: dart.dynamic, isMethod: core.bool, isGetter: core.bool, isSetter: core.bool})}),
     statics: () => ({_namedArgsToSymbols: dart.definiteFunctionType(core.Map$(core.Symbol, dart.dynamic), [dart.dynamic])}),
     names: ['_namedArgsToSymbols']
   });
@@ -2450,24 +2450,24 @@ dart_library.library('dart_sdk', null, /* Imports */[
       return dart.notNull(this.end) - dart.notNull(this.start);
     }
     get maxPowerOfSubsetSize() {
-      return (dart.notNull(math.log(core.num._check(dart.dsend(this.length, '-', 0.5)))) / dart.notNull(math.log(_debugger._maxSpanLength)))[dartx.truncate]();
+      return (dart.notNull(math.log(dart.notNull(this.length) - 0.5)) / dart.notNull(math.log(_debugger._maxSpanLength)))[dartx.truncate]();
     }
     get subsetSize() {
-      return math.pow(_debugger._maxSpanLength, core.num._check(this.maxPowerOfSubsetSize));
+      return dart.asInt(math.pow(_debugger._maxSpanLength, this.maxPowerOfSubsetSize));
     }
     asMap() {
-      return this.iterable[dartx.skip](this.start)[dartx.take](core.int._check(this.length))[dartx.toList]()[dartx.asMap]();
+      return this.iterable[dartx.skip](this.start)[dartx.take](this.length)[dartx.toList]()[dartx.asMap]();
     }
     children() {
       let ret = JSArrayOfNameValuePair().of([]);
-      if (dart.test(dart.dsend(this.length, '<=', _debugger._maxSpanLength))) {
-        dart.dsend(this.asMap(), 'forEach', dart.fn((i, element) => {
-          ret[dartx.add](new _debugger.NameValuePair({name: dart.toString(dart.dsend(i, '+', this.start)), value: element}));
-        }, dynamicAnddynamicTodynamic$()));
+      if (dart.notNull(this.length) <= dart.notNull(_debugger._maxSpanLength)) {
+        this.asMap()[dartx.forEach](dart.fn((i, element) => {
+          ret[dartx.add](new _debugger.NameValuePair({name: dart.toString(dart.notNull(i) + dart.notNull(this.start)), value: element}));
+        }, intAnddynamicTovoid()));
       } else {
-        for (let i = this.start; dart.notNull(i) < dart.notNull(this.end); i = dart.notNull(i) + dart.notNull(core.int._check(this.subsetSize))) {
-          let subSpan = new _debugger.IterableSpan(i, dart.asInt(math.min(core.num)(this.end, core.num._check(dart.dsend(this.subsetSize, '+', i)))), this.iterable);
-          if (dart.equals(subSpan.length, 1)) {
+        for (let i = this.start; dart.notNull(i) < dart.notNull(this.end); i = dart.notNull(i) + dart.notNull(this.subsetSize)) {
+          let subSpan = new _debugger.IterableSpan(i, math.min(core.int)(this.end, dart.notNull(this.subsetSize) + dart.notNull(i)), this.iterable);
+          if (subSpan.length == 1) {
             ret[dartx.add](new _debugger.NameValuePair({name: dart.toString(i), value: this.iterable[dartx.elementAt](i)}));
           } else {
             ret[dartx.add](new _debugger.NameValuePair({name: dart.str`[${i}...${dart.notNull(subSpan.end) - 1}]`, value: subSpan, hideName: true}));
@@ -2480,8 +2480,8 @@ dart_library.library('dart_sdk', null, /* Imports */[
   dart.setSignature(_debugger.IterableSpan, {
     constructors: () => ({new: dart.definiteFunctionType(_debugger.IterableSpan, [core.int, core.int, core.Iterable])}),
     methods: () => ({
-      asMap: dart.definiteFunctionType(dart.dynamic, []),
-      children: dart.definiteFunctionType(dart.dynamic, [])
+      asMap: dart.definiteFunctionType(core.Map$(core.int, dart.dynamic), []),
+      children: dart.definiteFunctionType(core.List$(_debugger.NameValuePair), [])
     })
   });
   _debugger.ClassMetadata = class ClassMetadata extends core.Object {
@@ -2833,7 +2833,7 @@ dart_library.library('dart_sdk', null, /* Imports */[
     }
     children(object) {
       let ret = LinkedHashSetOfNameValuePair().new();
-      ret.addAll(IterableOfNameValuePair()._check(new _debugger.IterableSpan(0, core.int._check(dart.dload(object, 'length')), core.Iterable._check(object)).children()));
+      ret.addAll(new _debugger.IterableSpan(0, core.int._check(dart.dload(object, 'length')), core.Iterable._check(object)).children());
       this.addMetadataChildren(object, ret);
       return ret.toList();
     }

pkg/dev_compiler/lib/src/compiler/code_generator.dart

@@ -545,7 +545,8 @@ class CodeGenerator extends GeneralizingAstVisitor
     var from = getStaticType(fromExpr);
     var to = node.type.type;
 
-    var jsFrom = _visit(fromExpr);
+    JS.Expression jsFrom = _visit(fromExpr);
+    if (_inWhitelistCode(node)) return jsFrom;
 
     // Skip the cast if it's not needed.
     if (rules.isSubtypeOf(from, to)) return jsFrom;
@@ -565,7 +566,6 @@ class CodeGenerator extends GeneralizingAstVisitor
     var type = _emitType(to,
         nameType: options.nameTypeTests || options.hoistTypeTests,
         hoistType: options.hoistTypeTests);
-    if (_inWhitelistCode(node)) return jsFrom;
     if (isReifiedCoercion(node)) {
       return js.call('#._check(#)', [type, jsFrom]);
     } else {
@@ -1311,6 +1311,8 @@ class CodeGenerator extends GeneralizingAstVisitor
       }
     }
 
+    jsMethods.addAll(_implementMockInterfaces(type));
+
     // If the type doesn't have an `iterator`, but claims to implement Iterable,
     // we inject the adaptor method here, as it's less code size to put the
     // helper on a parent class. This pattern is common in the core libraries
@@ -1330,6 +1332,151 @@ class CodeGenerator extends GeneralizingAstVisitor
     return jsMethods.where((m) => m != null).toList(growable: false);
   }
 
+  Iterable<ExecutableElement> _collectMockMethods(InterfaceType type) {
+    var element = type.element;
+    if (!_hasNoSuchMethod(element)) {
+      return [];
+    }
+
+    // Collect all unimplemented members.
+    //
+    // Initially, we track abstract and concrete members separately, then
+    // remove concrete from the abstract set. This is done because abstract
+    // members are allowed to "override" concrete ones in Dart.
+    // (In that case, it will still be treated as a concrete member and can be
+    // called at run time.)
+    var abstractMembers = new Map<String, ExecutableElement>();
+    var concreteMembers = new HashSet<String>();
+
+    void visit(InterfaceType type, bool isAbstract) {
+      if (type == null) return;
+      visit(type.superclass, isAbstract);
+      for (var m in type.mixins) visit(m, isAbstract);
+      for (var i in type.interfaces) visit(i, true);
+
+      var members = <ExecutableElement>[]
+        ..addAll(type.methods)
+        ..addAll(type.accessors);
+      for (var m in members) {
+        if (isAbstract || m.isAbstract) {
+          // Inconsistent signatures are disallowed, even with nSM, so we don't
+          // need to worry too much about which abstract member we save.
+          abstractMembers[m.name] = m;
+        } else {
+          concreteMembers.add(m.name);
+        }
+      }
+    }
+
+    visit(type, false);
+
+    concreteMembers.forEach(abstractMembers.remove);
+    return abstractMembers.values;
+  }
+
+  Iterable<JS.Method> _implementMockInterfaces(InterfaceType type) {
+    // TODO(jmesserly): every type with nSM will generate new stubs for all
+    // abstract members. For example:
+    //
+    //     class C { m(); noSuchMethod(...) { ... } }
+    //     class D extends C { m(); noSuchMethod(...) { ... } }
+    //
+    // We'll generate D.m even though it is not necessary.
+    //
+    // Doing better is a bit tricky, as our current codegen strategy for the
+    // mock methods encodes information about the number of arguments (and type
+    // arguments) that D expects.
+    return _collectMockMethods(type).map(_implementMockMethod);
+  }
+
+  /// Given a class C that implements method M from interface I, but does not
+  /// declare M, this will generate an implementation that forwards to
+  /// noSuchMethod.
+  ///
+  /// For example:
+  ///
+  ///     class Cat {
+  ///       bool eatFood(String food) => true;
+  ///     }
+  ///     class MockCat implements Cat {
+  ///        noSuchMethod(Invocation invocation) => 3;
+  ///     }
+  ///
+  /// It will generate an `eatFood` that looks like:
+  ///
+  ///     eatFood(food) {
+  ///       return core.bool.as(this.noSuchMethod(
+  ///           new dart.InvocationImpl('eatFood', [food])));
+  ///     }
+  JS.Method _implementMockMethod(ExecutableElement method) {
+    var positionalArgs = <JS.Identifier>[]
+      ..addAll(
+          method.type.normalParameterNames.map((a) => new JS.Identifier(a)))
+      ..addAll(
+          method.type.optionalParameterNames.map((a) => new JS.Identifier(a)));
+
+    var fnArgs = positionalArgs.toList();
+
+    var invocationProps = <JS.Property>[];
+    addProperty(String name, JS.Expression value) {
+      invocationProps.add(new JS.Property(js.string(name), value));
+    }
+
+    if (method.type.namedParameterTypes.isNotEmpty) {
+      fnArgs.add(namedArgumentTemp);
+      addProperty('namedArguments', namedArgumentTemp);
+    }
+
+    if (method is MethodElement) {
+      addProperty('isMethod', js.boolean(true));
+    } else {
+      var property = method as PropertyAccessorElement;
+      if (property.isGetter) {
+        addProperty('isGetter', js.boolean(true));
+      } else if (property.isSetter) {
+        addProperty('isSetter', js.boolean(true));
+      }
+    }
+
+    var fnBody =
+        js.call('this.noSuchMethod(new dart.InvocationImpl(#, #, #))', [
+      _elementMemberName(method),
+      new JS.ArrayInitializer(positionalArgs),
+      new JS.ObjectInitializer(invocationProps)
+    ]);
+
+    if (!method.returnType.isDynamic) {
+      fnBody = js.call('#._check(#)', [_emitType(method.returnType), fnBody]);
+    }
+
+    var fn = new JS.Fun(fnArgs, js.statement('{ return #; }', [fnBody]),
+        typeParams: _emitTypeFormals(method.type.typeFormals));
+
+    // TODO(jmesserly): generic type arguments will get dropped.
+    // We have a similar issue with `dgsend` helpers.
+    return new JS.Method(
+        _elementMemberName(method,
+            useExtension:
+                _extensionTypes.isNativeClass(method.enclosingElement)),
+        _makeGenericFunction(fn),
+        isGetter: method is PropertyAccessorElement && method.isGetter,
+        isSetter: method is PropertyAccessorElement && method.isSetter,
+        isStatic: false);
+  }
+
+  /// Return `true` if the given [classElement] has a noSuchMethod() method
+  /// distinct from the one declared in class Object, as per the Dart Language
+  /// Specification (section 10.4).
+  // TODO(jmesserly): this was taken from error_verifier.dart
+  bool _hasNoSuchMethod(ClassElement classElement) {
+    // TODO(jmesserly): this is slow in Analyzer. It's a linear scan through all
+    // methods, up through the class hierarchy.
+    MethodElement method = classElement.lookUpMethod(
+        FunctionElement.NO_SUCH_METHOD_METHOD_NAME, classElement.library);
+    var definingClass = method?.enclosingElement;
+    return definingClass != null && !definingClass.type.isObject;
+  }
+
   /// This is called whenever a derived class needs to introduce a new field,
   /// shadowing a field or getter/setter pair on its parent.
   ///

pkg/dev_compiler/lib/src/js_ast/nodes.dart

@@ -1175,6 +1175,7 @@ class Fun extends FunctionExpression {
   final Block body;
   @override final List<Identifier> typeParams;
   @override final TypeRef returnType;
+
   /** Whether this is a JS generator (`function*`) that may contain `yield`. */
   final bool isGenerator;
 

pkg/dev_compiler/pubspec.lock

@@ -234,7 +234,7 @@ packages:
       name: test
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.12.13+5"
+    version: "0.12.15+1"
   typed_data:
     description:
       name: typed_data
@@ -289,4 +289,4 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.9"
-sdk: ">=1.16.0 <1.19.0"
+sdk: ">=1.16.0 <1.20.0"

pkg/dev_compiler/test/browser/language_tests.js

@@ -259,7 +259,6 @@
       'nan_identical_test': skip_fail,
       'nested_switch_label_test': skip_fail,
       'no_such_method_empty_selector_test': fail,
-      'no_such_method_subtype_test': fail,
       'number_identifier_test_05_multi': skip_fail,
       'number_identity2_test': skip_fail,
       'numbers_test': skip_fail,