Support general expressions as keys in literal maps.

sdk/lib/_internal/compiler/implementation/compile_time_constants.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 dart2js;
 
 /**
  * The [ConstantHandler] keeps track of compile-time constants,
  * initializations of global and static fields, and default values of
  * optional parameters.
@@ skipping 368 matching lines @@
     handler.registerInstantiatedType(type, elements);
     Constant constant = new ListConstant(type, arguments);
     handler.registerCompileTimeConstant(constant, elements);
     return constant;
   }
 
   Constant visitLiteralMap(LiteralMap node) {
     if (!node.isConst()) {
       return signalNotCompileTimeConstant(node);
     }
-    List<StringConstant> keys = <StringConstant>[];
-    Map<StringConstant, Constant> map = new Map<StringConstant, Constant>();
+    List<Constant> keys = <Constant>[];
+    Map<Constant, Constant> map = new Map<Constant, Constant>();
     for (Link<Node> link = node.entries.nodes;
          !link.isEmpty;
          link = link.tail) {
       LiteralMapEntry entry = link.head;
       Constant key = evaluateConstant(entry.key);
-      if (!key.isString() || entry.key.asStringNode() == null) {
-        compiler.reportFatalError(
-            entry.key, MessageKind.KEY_NOT_A_STRING_LITERAL);
-      }
-      StringConstant keyConstant = key;
       if (!map.containsKey(key)) keys.add(key);
       map[key] = evaluateConstant(entry.value);
     }
+    bool hasNonStringKey = false;

[ngeoffray, 2013/09/13 07:30:15]

Negating names are confusing. How about 'onlyStringKeys'?

[Johnni Winther, 2013/09/18 12:37:21]

Done.

     List<Constant> values = <Constant>[];
     Constant protoValue = null;
-    for (StringConstant key in keys) {
-      if (key.value == MapConstant.PROTO_PROPERTY) {
+    for (Constant key in keys) {
+      if (key.isString() &&
+          (key as dynamic).value == MapConstant.PROTO_PROPERTY) {

[ngeoffray, 2013/09/13 07:30:15]

I'd prefer avoiding this as, and untype 'key'.

[Johnni Winther, 2013/09/18 12:37:21]

Done.

         protoValue = map[key];
       } else {
+        if (!key.isString()) {

[ngeoffray, 2013/09/13 07:30:15]

Checking twice here. I suggest:
if (key.isString()) {
  if (key.value == ...) {
    protoValue = 
  } else {
    values.add();
  }
} else {
  values.add();
  hasNonStringKey = true;
}

[Johnni Winther, 2013/09/18 12:37:21]

Completely rewritten.

+          hasNonStringKey = true;
+        }
         values.add(map[key]);
       }
     }
     bool hasProtoKey = (protoValue != null);
     InterfaceType sourceType = elements.getType(node);
     Link<DartType> arguments =
         new Link<DartType>.fromList([compiler.stringClass.rawType]);
     DartType keysType = new InterfaceType(compiler.listClass, arguments);
     ListConstant keysList = new ListConstant(keysType, keys);
-    handler.registerCompileTimeConstant(keysList, elements);
-    SourceString className = hasProtoKey
-                             ? MapConstant.DART_PROTO_CLASS
-                             : MapConstant.DART_CLASS;
+    if (!hasNonStringKey) {
+      handler.registerCompileTimeConstant(keysList, elements);
+    }
+    SourceString className = hasNonStringKey
+        ? MapConstant.DART_GENERAL_CLASS
+        : (hasProtoKey ? MapConstant.DART_PROTO_CLASS
+                       : MapConstant.DART_STRING_CLASS);
     ClassElement classElement = compiler.jsHelperLibrary.find(className);
     classElement.ensureResolved(compiler);
-    Link<DartType> typeArgument = sourceType.typeArguments.tail;
+    Link<DartType> typeArgument = sourceType.typeArguments;

[ngeoffray, 2013/09/13 07:30:15]

What is this change?

[Johnni Winther, 2013/09/18 12:37:21]

ConstantMap<V> implements Map<String, V> (and friends) are changed to
ConstantMap<K, V> implements Map<K, V>.

     InterfaceType type = new InterfaceType(classElement, typeArgument);
     handler.registerInstantiatedType(type, elements);
-    Constant constant = new MapConstant(type, keysList, values, protoValue);
+    Constant constant =
+        new MapConstant(type, keysList, values, protoValue, hasNonStringKey);
     handler.registerCompileTimeConstant(constant, elements);
     return constant;
   }
 
   Constant visitLiteralNull(LiteralNull node) {
     return constantSystem.createNull();
   }
 
   Constant visitLiteralString(LiteralString node) {
     handler.registerStringInstance(elements);
@@ skipping 510 matching lines @@
           if (fieldValue == null) {
             // Use the default value.
             fieldValue = handler.compileConstant(field);
           }
           jsNewArguments.add(fieldValue);
         },
         includeSuperAndInjectedMembers: true);
     return jsNewArguments;
   }
 }