Support user generated custom native JS classes.

pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart

 // Copyright (c) 2014, 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 dart2js.js_emitter.program_builder;
 
 import '../js_emitter.dart' show computeMixinClass, Emitter;
 import '../model.dart';
 
 import '../../common.dart';
 import '../../closure.dart' show ClosureFieldElement;
 import '../../js/js.dart' as js;
 
 import '../../js_backend/js_backend.dart' show
     Namer,
     JavaScriptBackend,
-    JavaScriptConstantCompiler;
+    JavaScriptConstantCompiler,
+    StringBackedName;
 
 import '../js_emitter.dart' show
     ClassStubGenerator,
     CodeEmitterTask,
     InterceptorStubGenerator,
     MainCallStubGenerator,
     ParameterStubGenerator,
     RuntimeTypeGenerator,
     TypeTestProperties;
 
 import '../../elements/elements.dart' show
     FieldElement,
     MethodElement,
+    Name,
     ParameterElement;
 
 import '../../universe/universe.dart' show Universe, ReceiverMaskSet;
 import '../../deferred_load.dart' show DeferredLoadTask, OutputUnit;
 
 part 'collector.dart';
 part 'registry.dart';
 part 'field_visitor.dart';
 
 /// Builds a self-contained representation of the program that can then be
@@ skipping 153 matching lines @@
     return loadMap;
   }
 
   js.Expression _buildTypeToInterceptorMap() {
     InterceptorStubGenerator stubGenerator =
         new InterceptorStubGenerator(_compiler, namer, backend);
     return stubGenerator.generateTypeToInterceptorMap();
   }
 
   MainFragment _buildMainFragment(LibrariesMap librariesMap) {
+    _buildJsInteropStubs(librariesMap);

[sra1, 2015/10/01 20:55:28]

_addJsInteropStubs()
By convention _buildXXX returns the thing, and does minimal damage.

Add the stubs before calling _buildMainFragment.

[Jacob, 2015/10/02 20:08:16]

Done.

     // Construct the main output from the libraries and the registered holders.
     MainFragment result = new MainFragment(
         librariesMap.outputUnit,
         "",  // The empty string is the name for the main output file.
         _buildInvokeMain(),
         _buildLibraries(librariesMap),
         _buildStaticNonFinalFields(librariesMap),
         _buildStaticLazilyInitializedFields(librariesMap),
         _buildConstants(librariesMap));
     _outputs[librariesMap.outputUnit] = result;
@@ skipping 98 matching lines @@
 
   List<Library> _buildLibraries(LibrariesMap librariesMap) {
     List<Library> libraries = new List<Library>(librariesMap.length);
     int count = 0;
     librariesMap.forEach((LibraryElement library, List<Element> elements) {
       libraries[count++] = _buildLibrary(library, elements);
     });
     return libraries;
   }
 
+  void _buildJsInteropStubs(LibrariesMap librariesMap) {
+    if (_classes.containsKey(_compiler.objectClass)) {
+      var toStringInvocation = namer.invocationName(new Selector.call(
+          new Name("toString", _compiler.objectClass.library),
+          CallStructure.NO_ARGS));
+      // TODO(jacobr): register toString as used so that it is always accessible
+      // from JavaScript.
+      _classes[_compiler.objectClass].callStubs.add(_buildStubMethod(
+          new StringBackedName("toString"),
+          js.js('function() { return this.#(this) }', toStringInvocation)));
+    }
+
+    // We add all members from classes marked with isJsInterop to the base
+    // Interceptor class with implementations that directly call the
+    // corresponding JavaScript member. We do not attempt to bind this when
+    // tearing off JavaScript methods as we cannot distinguish between calling
+    // a regular getter that returns a JavaScript function and tearing off
+    // a method in the case where there exist multiple JavaScript classes
+    // that conflict on whether the member is a getter or a method.
+    var interceptorClass = _classes[backend.jsInterceptorClass];
+    var stubNames = new Set<String>();
+    librariesMap.forEach((LibraryElement library, List<Element> elements) {
+      for (Element e in elements) {
+        if (e is ClassElement && e.isJsInterop) {
+          e.declaration.forEachMember((_, Element member) {
+            if (!member.isInstanceMember) return;
+            if (member.isGetter || member.isField || member.isFunction) {
+              var selectors =
+                  _compiler.codegenWorld.getterInvocationsByName(member.name);
+              if (selectors != null && !selectors.isEmpty) {
+                for (var selector in selectors.keys) {
+                  var stubName = namer.invocationName(selector);
+                  if (stubNames.add(stubName.key)) {
+                    interceptorClass.callStubs.add(_buildStubMethod(
+                        stubName,
+                        js.js(
+                            'function(obj) { return obj.# }', [member.name]),
+                        element: member));
+                  }
+                }
+              }
+            }
+
+            if (member.isSetter || (member.isField && !member.isConst)) {
+              var selectors =
+                  _compiler.codegenWorld.setterInvocationsByName(member.name);
+              if (selectors != null && !selectors.isEmpty) {
+                var stubName = namer.setterForElement(member);
+                if (stubNames.add(stubName.key)) {
+                  interceptorClass.callStubs.add(_buildStubMethod(
+                      stubName,
+                      js.js('function(obj, v) { return obj.# = v }',
+                          [member.name]),
+                      element: member));
+                }
+              }
+            }
+
+            if (member.isFunction) {
+              var selectors =
+                  _compiler.codegenWorld.invocationsByName(member.name);
+              FunctionElement fn = member;
+              // Named arguments are not yet supported. In the future we
+              // may want to map named arguments to an object literal containing
+              // all named arguments.
+              if (selectors != null && !selectors.isEmpty) {
+                for (var selector in selectors.keys) {
+                  // Check whether the arity matches this member.
+                  var argumentCount = selector.argumentCount;
+                  if (argumentCount > fn.parameters.length) break;
+                  if (argumentCount < fn.parameters.length &&
+                      !fn.parameters[argumentCount].isOptional) break;
+                  var stubName = namer.invocationName(selector);
+                  if (!stubNames.add(stubName.key)) break;
+                  var parameters = <js.Parameter>[];
+                  for (var i = 0; i < argumentCount; i++) {
+                    parameters.add(
+                        new js.Parameter(new String.fromCharCode(97 + i)));
+                  }

[sra1, 2015/10/01 20:55:28]

You can just use strings of names.

var parameters = new List<String>.generate(argumentCount,
  (i) => 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLOMOPQRSTUVWXYZ'[i]);

This will crash rather than generate bogus names for too many names.

----

Iterable<String> interpolates to multiple Parameters in parameter lists and
multiple VariableUse in argument lists.

(js.Parameter is a 'declaration' so should really only appear in function
parameter lists).

[Jacob, 2015/10/02 20:08:16]

Done.

+                  interceptorClass.callStubs.add(_buildStubMethod(
+                      stubName,
+                      js.js('function(obj, #) { return obj.#(#) }',

[sra1, 2015/10/01 20:55:28]

obj -> receiver for consistency with other stubs.

[Jacob, 2015/10/02 20:08:16]

Done.

+                          [parameters, member.name, parameters]),
+                          element: member));

[sra1, 2015/10/01 20:55:28]

indentation is off

[Jacob, 2015/10/02 20:08:15]

Done.

+                }
+              }
+            }
+          });
+        }
+      }
+    });
+  }
+
   // Note that a library-element may have multiple [Library]s, if it is split
   // into multiple output units.
   Library _buildLibrary(LibraryElement library, List<Element> elements) {
     String uri = library.canonicalUri.toString();
 
     List<StaticMethod> statics = elements
         .where((e) => e is FunctionElement)
         .map(_buildStaticMethod)
         .toList();
 
@@ skipping 27 matching lines @@
 
     return new Class(
         element, name, null, [], instanceFields, [], [], [], [], [], [], null,
         isDirectlyInstantiated: true,
         onlyForRti: false,
         isNative: element.isNative);
   }
 
   Class _buildClass(ClassElement element) {
     bool onlyForRti = collector.classesOnlyNeededForRti.contains(element);
+    bool onlyJsInterop = element.isJsInterop;
+    if (onlyJsInterop) {
+      // TODO(jacobr): check whether the class has any active static fields
+      // if it does not we can suppress it completelly. 
+      onlyForRti = true;
+    }
 
     List<Method> methods = [];
     List<StubMethod> callStubs = <StubMethod>[];
 
     ClassStubGenerator classStubGenerator =
-        new ClassStubGenerator(_compiler, namer, backend);
+    new ClassStubGenerator(_compiler, namer, backend);

[sra1, 2015/10/01 20:55:28]

repair indentation

[Jacob, 2015/10/02 20:08:16]

Done.

     RuntimeTypeGenerator runtimeTypeGenerator =
-        new RuntimeTypeGenerator(_compiler, _task, namer);
+    new RuntimeTypeGenerator(_compiler, _task, namer);

[sra1, 2015/10/01 20:55:28]

ditto

[Jacob, 2015/10/02 20:08:15]

Done.

 
     void visitMember(ClassElement enclosing, Element member) {
       assert(invariant(element, member.isDeclaration));
       assert(invariant(element, element == enclosing));
 
       if (Elements.isNonAbstractInstanceMember(member)) {
         // TODO(herhut): Remove once _buildMethod can no longer return null.
         Method method = _buildMethod(member);
         if (method != null) methods.add(method);
       }
       if (member.isGetter || member.isField) {
         Map<Selector, ReceiverMaskSet> selectors =
             _compiler.codegenWorld.invocationsByName(member.name);
         if (selectors != null && !selectors.isEmpty) {
 
           Map<js.Name, js.Expression> callStubsForMember =
-              classStubGenerator.generateCallStubsForGetter(member, selectors);
+          classStubGenerator.generateCallStubsForGetter(member, selectors);

[sra1, 2015/10/01 20:55:28]

ditto

[Jacob, 2015/10/02 20:08:15]

Done.

           callStubsForMember.forEach((js.Name name, js.Expression code) {
             callStubs.add(_buildStubMethod(name, code, element: member));
           });
         }
       }
     }
 
     List<StubMethod> typeVariableReaderStubs =
-        runtimeTypeGenerator.generateTypeVariableReaderStubs(element);
+    runtimeTypeGenerator.generateTypeVariableReaderStubs(element);

[sra1, 2015/10/01 20:55:28]

ditto

[Jacob, 2015/10/02 20:08:16]

done... arghhh... intelij

 
     List<StubMethod> noSuchMethodStubs = <StubMethod>[];
 
     if (backend.enabledNoSuchMethod && element == _compiler.objectClass) {
       Map<js.Name, Selector> selectors =
-          classStubGenerator.computeSelectorsForNsmHandlers();
+      classStubGenerator.computeSelectorsForNsmHandlers();

[sra1, 2015/10/01 20:55:28]

ditto

[Jacob, 2015/10/02 20:08:15]

Done.

       selectors.forEach((js.Name name, Selector selector) {
         // If the program contains `const Symbol` names we have to retain them.
         String selectorName = selector.name;
         if (selector.isSetter) selectorName = "$selectorName=";
         if (backend.symbolsUsed.contains(selectorName)) {
           _symbolsMap[name] = selectorName;
         }
         noSuchMethodStubs
-            .add(classStubGenerator.generateStubForNoSuchMethod(name,
-                                                                selector));
+        .add(classStubGenerator.generateStubForNoSuchMethod(name,
+        selector));

[sra1, 2015/10/01 20:55:28]

ditto

[Jacob, 2015/10/02 20:08:16]

Done.

       });
     }
 
     if (element == backend.closureClass) {
       // We add a special getter here to allow for tearing off a closure from
       // itself.
       js.Name name = namer.getterForMember(Selector.CALL_NAME);
       js.Fun function = js.js('function() { return this; }');
       callStubs.add(_buildStubMethod(name, function));
     }
 
     ClassElement implementation = element.implementation;
 
     // MixinApplications run through the members of their mixin. Here, we are
     // only interested in direct members.
     if (!onlyForRti && !element.isMixinApplication) {
       implementation.forEachMember(visitMember, includeBackendMembers: true);
     }
 
     List<Field> instanceFields =
-        onlyForRti ? const <Field>[] : _buildFields(element, false);
+    onlyForRti ? const <Field>[] : _buildFields(element, false);

[sra1, 2015/10/01 20:55:28]

ditto

[Jacob, 2015/10/02 20:08:16]

Done.

     List<Field> staticFieldsForReflection =
-        onlyForRti ? const <Field>[] : _buildFields(element, true);
+    onlyForRti ? const <Field>[] : _buildFields(element, true);
 
     TypeTestProperties typeTests =
-        runtimeTypeGenerator.generateIsTests(
-            element,
-            storeFunctionTypeInMetadata: _storeFunctionTypesInMetadata);
+    runtimeTypeGenerator.generateIsTests(
+        element,
+        storeFunctionTypeInMetadata: _storeFunctionTypesInMetadata);
 
     List<StubMethod> checkedSetters = <StubMethod>[];
-    for (Field field in instanceFields) {
-      if (field.needsCheckedSetter) {
-        assert(!field.needsUncheckedSetter);
-        Element element = field.element;
-        js.Expression code = backend.generatedCode[element];
-        assert(code != null);
-        js.Name name = namer.deriveSetterName(field.accessorName);
-        checkedSetters.add(_buildStubMethod(name, code, element: element));
+    List<StubMethod> isChecks = <StubMethod>[];
+    if (!onlyJsInterop) {
+      for (Field field in instanceFields) {
+        if (field.needsCheckedSetter) {
+          assert(!field.needsUncheckedSetter);
+          Element element = field.element;
+          js.Expression code = backend.generatedCode[element];
+          assert(code != null);
+          js.Name name = namer.deriveSetterName(field.accessorName);
+          checkedSetters.add(_buildStubMethod(name, code, element: element));
+        }
       }
+
+      typeTests.properties.forEach((js.Name name, js.Node code) {
+        isChecks.add(_buildStubMethod(name, code));
+      });
     }
-
-    List<StubMethod> isChecks = <StubMethod>[];
-    typeTests.properties.forEach((js.Name name, js.Node code) {
-      isChecks.add(_buildStubMethod(name, code));
-    });
+    if (element.isJsInterop) {

[sra1, 2015/10/01 20:55:28]

use one of element.isJsInterop or onlyJsInterop consistently.

[Jacob, 2015/10/02 20:08:16]

Done.

+      // TODO(jacobr): make sure we aren't adding the same is checks multiple times..

[sra1, 2015/10/01 20:55:28]

line lengyh

[Jacob, 2015/10/02 20:08:15]

fixedh

+      typeTests.properties.forEach((js.Name name, js.Node code) {
+        _classes[backend.jsInterceptorClass].isChecks.add(_buildStubMethod(name, code));
+      });
+    }
 
     js.Name name = namer.className(element);
     String holderName = namer.globalObjectFor(element);
     // TODO(floitsch): we shouldn't update the registry in the middle of
     // building a class.
     Holder holder = _registry.registerHolder(holderName);
-    bool isInstantiated =
-        _compiler.codegenWorld.directlyInstantiatedClasses.contains(element);
+    bool isInstantiated = onlyJsInterop ? false :
+    _compiler.codegenWorld.directlyInstantiatedClasses.contains(element);
 
     Class result;
     if (element.isMixinApplication && !onlyForRti) {
       assert(!element.isNative);
       assert(methods.isEmpty);
 
       result = new MixinApplication(element,
                                     name, holder,
                                     instanceFields,
                                     staticFieldsForReflection,
@@ skipping 347 matching lines @@
       Constant constant = new Constant(name, holder, constantValue);
       _constants[constantValue] = constant;
     }
   }
 
   Holder _registerStaticStateHolder() {
     return _registry.registerHolder(
         namer.staticStateHolder, isStaticStateHolder: true);
   }
 }