Check that const-map keys don't override equals.

BUG= http://dartbug.com/17123
R=karlklose@google.com

Review URL: https://codereview.chromium.org//179293005

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@33201 260f80e4-7a28-3924-810f-c04153c831b5

sdk/lib/_internal/compiler/implementation/resolution/members.dart

@@ -3098,11 +3098,32 @@ class ResolverVisitor extends MappingVisitor<Element> {
     return null;
   }
 
+  void checkConstMapKeysDontOverrideEquals(Spannable spannable,
+                                           MapConstant map) {
+    for (Constant key in map.keys.entries) {
+      if (!key.isObject()) continue;
+      ObjectConstant objectConstant = key;
+      DartType keyType = objectConstant.type;
+      ClassElement cls = keyType.element;
+      if (cls == compiler.stringClass) continue;
+      Element equals = cls.lookupMember('==');
+      if (equals.getEnclosingClass() != compiler.objectClass) {
+        compiler.reportError(spannable,
+                             MessageKind.CONST_MAP_KEY_OVERRIDES_EQUALS,
+                             {'type': keyType});
+      }
+    }
+  }
+
   void analyzeConstant(Node node, {bool isConst: true}) {
     addDeferredAction(enclosingElement, () {
       Constant constant = compiler.constantHandler.compileNodeWithDefinitions(
           node, mapping, isConst: isConst);
 
+      if (isConst && constant != null && constant.isMap()) {
+        checkConstMapKeysDontOverrideEquals(node, constant);
+      }
+
       // The type constant that is an argument to JS_INTERCEPTOR_CONSTANT names
       // a class that will be instantiated outside the program by attaching a
       // native class dispatch record referencing the interceptor.

sdk/lib/_internal/compiler/implementation/warnings.dart

@@ -556,8 +556,9 @@ main() => new C<String>();
   static const MessageKind CONSTRUCTOR_IS_NOT_CONST = const MessageKind(
       "Constructor is not a 'const' constructor.");
 
-  static const MessageKind KEY_NOT_A_STRING_LITERAL = const MessageKind(
-      "Map-literal key not a string literal.");
+  static const MessageKind CONST_MAP_KEY_OVERRIDES_EQUALS =
+      const MessageKind(
+          "Const-map key type '#{type}' overrides 'operator =='.");
 
   static const MessageKind NO_SUCH_LIBRARY_MEMBER = const MessageKind(
       "'#{libraryName}' has no member named '#{memberName}'.");

tests/co19/co19-dart2js.status

@@ -260,6 +260,7 @@ LibTest/math/cos_A01_t01: Fail # co19 issue 44
 [ $compiler == dart2js ]
 Language/07_Classes/6_Constructors/1_Generative_Constructors_A13_t01: RuntimeError # compiler cancelled: cannot resolve type T
 Language/07_Classes/3_Setters_A04_t03: RuntimeError # http://dartbug.com/5023
+Language/12_Expressions/07_Maps_A11_t01: CompileTimeError # Maybe ok. Issue 17207
 
 [ $compiler == dart2js && $jscl ]
 LibTest/core/RegExp/Pattern_semantics/firstMatch_CharacterEscape_A06_t02: RuntimeError # IllegalJSRegExpException: '\c(' 'SyntaxError: Invalid regular expression: /\c(/: Unterminated group'
@@ -638,7 +639,6 @@ Language/07_Classes/6_Constructors/2_Factories_A10_t02: fail # co19-roll r587: P
 Language/07_Classes/6_Constructors/2_Factories_A10_t03: fail # co19-roll r587: Please triage this failure
 Language/10_Generics/09_Generics_A01_t17: fail # co19-roll r587: Please triage this failure
 Language/12_Expressions/06_Symbols_A01_t02: CompileTimeError # co19-roll r623: Please triage this failure
-Language/12_Expressions/07_Maps_A13_t01: MissingCompileTimeError # co19-roll r607: Please triage this failure
 Language/12_Expressions/12_Instance_Creation/1_New_A06_t15: CompileTimeError # co19-roll r651: Please triage this failure
 Language/12_Expressions/14_Function_Invocation/3_Unqualified_Invocation_A01_t17: MissingCompileTimeError # co19-roll r651: Please triage this failure
 Language/12_Expressions/14_Function_Invocation/3_Unqualified_Invocation_A01_t18: MissingCompileTimeError # co19-roll r651: Please triage this failure

tests/language/const_map2_test.dart

@@ -0,0 +1,29 @@
+// Copyright (c) 2014, 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.
+
+import "package:expect/expect.dart";
+
+class A {
+  const factory A() = B;
+}
+
+class B implements A {
+  const B();
+
+  operator ==(o) => true;  /// 00: compile-time error
+}
+
+confuse(x) {
+  if (new DateTime.now() == 42) return confuse(2);
+  return x;
+}
+
+main() {
+  // It is a compile-time error if the key type overrides operator ==.
+  var m = const { const A(): 42 };
+  Expect.equals(42, m[confuse(const B())]);
+
+  m = const { "foo": 99, const A(): 499 };
+  Expect.equals(499, m[confuse(const B())]);
+}

tests/language/language.status

@@ -27,6 +27,9 @@ deferred_duplicate_prefix1_test/01: Fail
 deferred_duplicate_prefix2_test/01: Fail
 deferred_duplicate_prefix3_test/01: Fail
 
+[ $compiler == dartanalyzer ]
+const_map2_test/00: MissingCompileTimeError # Issue 17209
+
 [ $compiler == none && $runtime == vm ]
 class_keyword_test/02: MissingCompileTimeError # Issue 13627
 override_inheritance_mixed_test/08: MissingCompileTimeError # Issue 16137