Make super.foo= erroneous if they are not assignable.

pkg/compiler/lib/src/resolution/members.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 resolution;
 
 abstract class TreeElements {
   AnalyzableElement get analyzedElement;
   Iterable<Node> get superUses;
 
@@ skipping 2994 matching lines @@
         if (isComplex && getter == null && !inInstanceContext) {
           getter = reportAndCreateErroneousElement(node.selector, field.name,
               MessageKind.CANNOT_RESOLVE_GETTER, const {});
           registry.registerThrowNoSuchMethod();
         }
       } else if (target.impliesType) {
         setter = reportAndCreateErroneousElement(node.selector, target.name,
             MessageKind.ASSIGNING_TYPE, const {});
         registry.registerThrowNoSuchMethod();
       } else if (target.isFinal || target.isConst) {
-        if (Elements.isStaticOrTopLevelField(target) || target.isLocal) {
+        if (Elements.isStaticOrTopLevelField(target) || target.isLocal ||
+            node.isSuperCall || node.isThisCall) {

[Johnni Winther, 2015/04/17 12:17:37]

Remove `node.isThisCall`. It is not a statically known runtime error and we
should only report a warning from typechecker, if any:

class A {
  final a = 42;
  m() {
    this.a = 43; // warning in typechecker
  }
}
main() => new A().m(); // runtime error with NSM

class B {
  var a;
}
class A implements B { // warning about unimplemented a=
  final a = 42;
  m() {
    a = 43; // no warning in typechecker
  }
}
main() => new A().m(); // runtime error with NSM

class A {
  final a = 42;
  m() {
    a = 43; // warning in typechecker
  }
}
class B extends A {
  set a(_) {}
}
main() => new B().m(); // no runtime error

[Siggi Cherem (dart-lang), 2015/04/17 16:38:24]

Good call. Done.

           setter = reportAndCreateErroneousElement(
               node.selector, target.name, MessageKind.CANNOT_RESOLVE_SETTER,
               const {});
         } else {
-          // For instance fields we don't report a warning here because the type
-          // checker will detect this as well and report a better error message
-          // with the context of the containing class.
+          // For implicit instance fields we don't report a warning here because
+          // the type checker will detect this as well and report a better error
+          // message with the context of the containing class.
         }
         registry.registerThrowNoSuchMethod();
         if (node.isSuperCall) registry.registerSuperNoSuchMethod();

[Johnni Winther, 2015/04/17 12:17:37]

I would special case super calls here, creating an erroneous element with a
specialized method.

[Siggi Cherem (dart-lang), 2015/04/17 16:38:24]

Not sure I completely followed - when you say a specialized method, you meant a
specialized message? If so, done :)

[Johnni Winther, 2015/04/17 17:56:09]

'method' -> 'message' !

       } else if (target.isFunction && target.name != '[]=') {
         assert(!target.isSetter);
-        if (Elements.isStaticOrTopLevelFunction(target) || target.isLocal) {
+        if (Elements.isStaticOrTopLevelFunction(target) || target.isLocal ||
+          node.isSuperCall || node.isThisCall) {

[Johnni Winther, 2015/04/17 12:17:37]

Similarly regarding `node.isThisCall`. The class could have more complex
hiearchy making this a pure runtime error or even no error.

[Siggi Cherem (dart-lang), 2015/04/17 16:38:23]

Done.

           setter = reportAndCreateErroneousElement(
               node.selector, target.name, MessageKind.ASSIGNING_METHOD,
               const {});
         } else {
-          // For instance methods we don't report a warning here because the
-          // type checker will detect this as well and report a better error
-          // message with the context of the containing class.
+          // For implicit instance methods we don't report a warning here
+          // because the type checker will detect this as well and report a
+          // better error message with the context of the containing class.
         }
         registry.registerThrowNoSuchMethod();
         if (node.isSuperCall) registry.registerSuperNoSuchMethod();

[Johnni Winther, 2015/04/17 12:17:37]

I would special case super calls here, creating an erroneous element with a
specialized method.

[Siggi Cherem (dart-lang), 2015/04/17 16:38:24]

Done.

       }
       if (isPotentiallyMutableTarget(target)) {
         registry.registerPotentialMutation(target, node);
         if (enclosingElement != target.enclosingElement) {
           registry.registerPotentialMutationInClosure(target, node);
         }
         for (Node scope in promotionScope) {
           registry.registerPotentialMutationIn(scope, target, node);
         }
       }
@@ skipping 2076 matching lines @@
 }
 
 /// The result for the resolution of the `assert` method.
 class AssertResult implements ResolutionResult {
   const AssertResult();
 
   Element get element => null;
 
   String toString() => 'AssertResult()';
 }