Rewrite how we handle synthesized constructors in the compiler. This was motivated by issue https:/…

sdk/lib/_internal/compiler/implementation/ssa/codegen.dart

 // Copyright (c) 2012, 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.
 
 part of ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
 
   SsaCodeGeneratorTask(JavaScriptBackend backend)
       : this.backend = backend,
         super(backend.compiler);
   String get name => 'SSA code generator';
   NativeEmitter get nativeEmitter => backend.emitter.nativeEmitter;
 
 
   js.Fun buildJavaScriptFunction(FunctionElement element,
                                  List<js.Parameter> parameters,
                                  js.Block body) {
-    FunctionExpression expression =
-        element.implementation.parseNode(backend.compiler);
     js.Fun result = new js.Fun(parameters, body);
     // TODO(johnniwinther): remove the 'element.patch' hack.
     Element sourceElement = element.patch == null ? element : element.patch;
     SourceFile sourceFile = sourceElement.getCompilationUnit().script.file;
+    Node expression =
+        element.implementation.parseNode(backend.compiler);
+    if (expression == null) {
+      // Synthesized node. Use the enclosing element for the location.
+      expression = element.enclosingElement.parseNode(backend.compiler);

[ahe, 2013/07/18 09:59:32]

I'm not sure about this. I'll suggest an alternative on second pass.

[ahe, 2013/07/18 14:32:56]

Spannable spannable = element.implementation.parseNode(backend.compiler);
if (spannable == null) {
  assert(invariant(element, element.isSynthetic));
  spannable = element.enclosingElement;
}
SourceSpan span = spanFromSpannable(spannable);
// TODO(podivilov): find the right sourceFile here and remove offset checks
// below.
if (span.begin < sourceFile.text.length) {
...

[ngeoffray, 2013/07/18 15:25:14]

Done.

+    }
     // TODO(podivilov): find the right sourceFile here and remove offset checks
     // below.
     if (expression.getBeginToken().charOffset < sourceFile.text.length) {
       result.sourcePosition = new SourceFileLocation(
           sourceFile, expression.getBeginToken());
     }
     if (expression.getEndToken().charOffset < sourceFile.text.length) {
       result.endSourcePosition = new SourceFileLocation(
           sourceFile, expression.getEndToken());
     }
@@ skipping 2939 matching lines @@
   if (leftType.canBeNull() && rightType.canBeNull()) {
     if (left.isConstantNull() || right.isConstantNull() ||
         (leftType.isPrimitive(compiler) && leftType == rightType)) {
       return '==';
     }
     return null;
   } else {
     return '===';
   }
 }