Do not use erroneouselement unless the member is static

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) {
-        setter = reportAndCreateErroneousElement(
+        if (Elements.isStaticOrTopLevelField(target)) {

[Harry Terkelsen, 2015/04/15 18:22:34]

this check causes this to print '2':

class A {
  foo() {
    final bar = 1;
    bar = 2;
    print(bar);
  }
}
main() => new A().foo();

[Siggi Cherem (dart-lang), 2015/04/15 22:39:46]

Good catch Harry, this should also test for isLocal like I was doing below with
the local functions.

I added it here and added some tests for the warnings.

+          setter = reportAndCreateErroneousElement(
               node.selector, target.name, MessageKind.CANNOT_RESOLVE_SETTER,
               const {});
+        } else {
+          compiler.reportWarning(node.selector,
+              MessageKind.CANNOT_RESOLVE_SETTER);
+        }
         registry.registerThrowNoSuchMethod();
       } else if (target.isFunction && target.name != '[]=') {
         assert(!target.isSetter);
-        setter = reportAndCreateErroneousElement(
-            node.selector, target.name, MessageKind.ASSIGNING_METHOD, const {});
+        if (Elements.isStaticOrTopLevelFunction(target) || target.isLocal) {
+          setter = reportAndCreateErroneousElement(
+              node.selector, target.name, MessageKind.ASSIGNING_METHOD,
+              const {});
+        } else {
+          compiler.reportWarning(node.selector, MessageKind.ASSIGNING_METHOD);
+        }
         registry.registerThrowNoSuchMethod();
         if (node.isSuperCall) registry.registerSuperNoSuchMethod();
       }
       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 2078 matching lines @@
 }
 
 /// The result for the resolution of the `assert` method.
 class AssertResult implements ResolutionResult {
   const AssertResult();
 
   Element get element => null;
 
   String toString() => 'AssertResult()';
 }