dart2js-kernel: Call generative constructor body functions

pkg/compiler/lib/src/elements/modelx.dart

 // Copyright (c) 2013, 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 elements.modelx;
 
 import '../common.dart';
 import '../common/names.dart' show Identifiers;
 import '../common/resolution.dart' show Resolution, ParsingContext;
 import '../compiler.dart' show Compiler;
@@ skipping 2396 matching lines @@
 
   ConstructorBodyElementX(
       ResolvedAst resolvedAst, ConstructorElement constructor)
       : this._resolvedAst = resolvedAst,
         this.constructor = constructor,
         super(constructor.name, ElementKind.GENERATIVE_CONSTRUCTOR_BODY,
             Modifiers.EMPTY, constructor.enclosingElement) {
     functionSignature = constructor.functionSignature;
   }
 
+  /// Returns the constructor body associated with the given constructor or
+  /// creates a new constructor body, if none can be found.
+  ///
+  /// Returns `null` if the constructor does not have a body.
+  static ConstructorBodyElementX createFromResolvedAst(
+      ResolvedAst constructorResolvedAst) {
+    ConstructorElement constructor =
+        constructorResolvedAst.element.implementation;
+    assert(constructor.isGenerativeConstructor);
+    if (constructorResolvedAst.kind != ResolvedAstKind.PARSED) return null;
+
+    FunctionExpression node = constructorResolvedAst.node;
+    // If we know the body doesn't have any code, we don't generate it.
+    if (!node.hasBody) return null;
+    if (node.hasEmptyBody) return null;
+    ClassElement classElement = constructor.enclosingClass;
+    ConstructorBodyElement bodyElement;
+    classElement.forEachBackendMember((Element backendMember) {
+      if (backendMember.isGenerativeConstructorBody) {
+        ConstructorBodyElement body = backendMember;
+        if (body.constructor == constructor) {
+          // TODO(kasperl): Find a way of stopping the iteration
+          // through the backend members.
+          bodyElement = backendMember;
+        }
+      }
+    });
+    if (bodyElement == null) {
+      bodyElement =
+          new ConstructorBodyElementX(constructorResolvedAst, constructor);
+      classElement.addBackendMember(bodyElement);
+
+      if (constructor.isPatch) {
+        // Create origin body element for patched constructors.
+        ConstructorBodyElementX patch = bodyElement;
+        ConstructorBodyElementX origin = new ConstructorBodyElementX(
+            constructorResolvedAst, constructor.origin);
+        origin.applyPatch(patch);
+        classElement.origin.addBackendMember(bodyElement.origin);
+      }
+    }
+    assert(bodyElement.isGenerativeConstructorBody);
+    return bodyElement;
+  }
+
   bool get hasNode => _resolvedAst.kind == ResolvedAstKind.PARSED;
 
   FunctionExpression get node => _resolvedAst.node;
 
   bool get hasResolvedAst => true;
 
   ResolvedAst get resolvedAst {
     if (_resolvedAst.kind == ResolvedAstKind.PARSED) {
       return new ParsedResolvedAst(declaration, _resolvedAst.node,
           _resolvedAst.body, _resolvedAst.elements, _resolvedAst.sourceUri);
@@ skipping 994 matching lines @@
       body = node.asFunctionExpression().body;
     }
     return new ParsedResolvedAst(
         declaration,
         node,
         body,
         definingElement.treeElements,
         definingElement.compilationUnit.script.resourceUri);
   }
 }