Support type variables on redirecting factory constructors.

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

Index: sdk/lib/_internal/compiler/implementation/ssa/builder.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/builder.dart b/sdk/lib/_internal/compiler/implementation/ssa/builder.dart
index 064a52e1e9d17b601b616bc2e70046c6282e69eb..b9715a7d96c1db8490cd57a307f2dbd4c1356024 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/builder.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/builder.dart
@@ -3231,8 +3231,31 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
     if (compiler.enqueuer.resolution.getCachedElements(constructor) == null) {
       compiler.internalError("Unresolved element: $constructor", node: node);
     }
+
+    // Compute the right target and type for redirecting generative and

[ngeoffray, 2013/02/18 09:44:28]

What's a redirecting generative constructor?

[karlklose, 2013/02/19 13:20:27]

One that uses this(...), but they never actually end here, the comment was
wrong. Removed it.

+    // factory constructors.
     FunctionElement functionElement = constructor;
-    constructor = functionElement.redirectionTarget;
+    if (functionElement.redirectionTarget != functionElement) {

[ngeoffray, 2013/02/18 09:44:28]

Shouldn't you get the redirectionTarget until it's null?

[karlklose, 2013/02/19 13:20:27]

Yes. It does not matter currently, because we bail out for multiple
redirections.

+      FunctionExpression functionNode = constructor.parseNode(compiler);
+      if (functionNode.isRedirectingFactory) {
+        // Lookup the type expression used in the body and substitute the type
+        // variables with the call's type arguments in it.
+        Return redirectionNode = functionNode.body;
+        TreeElements treeElements =
+            compiler.enqueuer.resolution.getCachedElements(
+                constructor.declaration);
+        ClassElement targetClass = constructor.getEnclosingClass();
+        DartType targetType = treeElements.getType(redirectionNode.expression);
+        Link<DartType> typeVariables = targetClass.typeVariables;
+        Link<DartType> typeArguments = type.typeArguments;
+        type = targetType.subst(typeArguments, typeVariables);
+      }
+      constructor = functionElement.redirectionTarget;
+    }
+
+    // TODO(karlklose): move this type registration to the codegen.
+    compiler.codegenWorld.instantiatedTypes.add(type);
+
     // TODO(5346): Try to avoid the need for calling [declaration] before
     // creating an [HStatic].
     HInstruction target = new HStatic(constructor.declaration);
@@ -3491,8 +3514,6 @@ class SsaBuilder extends ResolvedVisitor implements Visitor {
         // on type arguments.
         generateRuntimeError(node, '$type is malformed: $reasons');
       } else {
-        // TODO(karlklose): move this type registration to the codegen.
-        compiler.codegenWorld.instantiatedTypes.add(type);
         visitNewSend(node.send, type);
       }
     }