Revert "Minifying renamer for classes, methods and instance variables."

lib/compiler/implementation/js_backend/namer.dart

Index: lib/compiler/implementation/js_backend/namer.dart
diff --git a/lib/compiler/implementation/js_backend/namer.dart b/lib/compiler/implementation/js_backend/namer.dart
index c8522a068bad71a3480c4f3a47cd5672771523dd..1236aa6d9f53ec48e24144c588f420c7b02b82be 100644
--- a/lib/compiler/implementation/js_backend/namer.dart
+++ b/lib/compiler/implementation/js_backend/namer.dart
@@ -8,6 +8,8 @@ part of js_backend;
  * Assigns JavaScript identifiers to Dart variables, class-names and members.
  */
 class Namer {
+  final Compiler compiler;
+
   static Set<String> _jsReserved = null;
   Set<String> get jsReserved {
     if (_jsReserved == null) {
@@ -18,44 +20,32 @@ class Namer {
     return _jsReserved;
   }
 
-  final String CURRENT_ISOLATE = r'$';
-
   /**
    * Map from top-level or static elements to their unique identifiers provided
    * by [getName].
    *
    * Invariant: Keys must be declaration elements.
    */
-  final Compiler compiler;
   final Map<Element, String> globals;
+  final Map<String, int> usedGlobals;
   final Map<String, LibraryElement> shortPrivateNameOwners;
-  final Set<String> usedGlobalNames;
-  final Set<String> usedInstanceNames;
-  final Map<String, String> instanceNameMap;
-  final Map<String, String> globalNameMap;
-  final Map<String, int> popularNameCounters;
 
   final Map<Constant, String> constantNames;
 
   Namer(this.compiler)
       : globals = new Map<Element, String>(),
+        usedGlobals = new Map<String, int>(),
         shortPrivateNameOwners = new Map<String, LibraryElement>(),
-        usedGlobalNames = new Set<String>(),
-        usedInstanceNames = new Set<String>(),
-        instanceNameMap = new Map<String, String>(),
-        globalNameMap = new Map<String, String>(),
-        constantNames = new Map<Constant, String>(),
-        popularNameCounters = new Map<String, int>();
-
-  String get ISOLATE => 'Isolate';
-  String get ISOLATE_PROPERTIES => r'$isolateProperties';
+        constantNames = new Map<Constant, String>();
+
+  final String CURRENT_ISOLATE = r'$';
+  final String ISOLATE = 'Isolate';
+  final String ISOLATE_PROPERTIES = r"$isolateProperties";
   /** Some closures must contain their name. The name is stored in
     * [STATIC_CLOSURE_NAME_NAME]. */
-  String get STATIC_CLOSURE_NAME_NAME => r'$name';
-  SourceString get CLOSURE_INVOCATION_NAME => Compiler.CALL_OPERATOR_NAME;
-  bool get shouldMinify => false;
-
-  bool isReserved(String name) => name == ISOLATE;
+  final String STATIC_CLOSURE_NAME_NAME = r'$name';
+  static const SourceString CLOSURE_INVOCATION_NAME =
+      Compiler.CALL_OPERATOR_NAME;
 
   String constantName(Constant constant) {
     // In the current implementation it doesn't make sense to give names to
@@ -64,26 +54,16 @@ class Namer {
     assert(!constant.isFunction());
     String result = constantNames[constant];
     if (result == null) {
-      String longName;
-      if (shouldMinify) {
-        if (constant.isString()) {
-          StringConstant stringConstant = constant;
-          longName = stringConstant.value.slowToString();
-        } else {
-          longName = "C";
-        }
-      } else {
-        longName = "CTC";
-      }
-      result = getFreshName(longName, usedGlobalNames);
+      result = getFreshGlobalName("CTC");
       constantNames[constant] = result;
     }
     return result;
   }
 
   String closureInvocationName(Selector selector) {
-    return
-        instanceMethodInvocationName(null, CLOSURE_INVOCATION_NAME, selector);
+    // TODO(floitsch): mangle, while not conflicting with instance names.
+    return instanceMethodInvocationName(null, CLOSURE_INVOCATION_NAME,
+                                        selector);
   }
 
   String breakLabelName(LabelElement label) {
@@ -109,7 +89,6 @@ class Namer {
    * mangles the [name] so that each library has a unique name.
    */
   String privateName(LibraryElement lib, SourceString name) {
-    String result;
     if (name.isPrivate()) {
       String nameString = name.slowToString();
       // The first library asking for a short private name wins.
@@ -118,22 +97,17 @@ class Namer {
       // If a private name could clash with a mangled private name we don't
       // use the short name. For example a private name "_lib3_foo" would
       // clash with "_foo" from "lib3".
-      if (owner == lib &&
-          !nameString.startsWith('_$LIBRARY_PREFIX') &&
-          !shouldMinify) {
-        result = nameString;
-      } else {
-        String libName = getName(lib);
-        // If a library name does not start with the [LIBRARY_PREFIX] then our
-        // assumptions about clashing with mangled private members do not hold.
-        assert(shouldMinify || libName.startsWith(LIBRARY_PREFIX));
-        // TODO(erikcorry): Fix this with other manglings to avoid clashes.
-        result = '_lib$libName\$$nameString';
+      if (identical(owner, lib) && !nameString.startsWith('_$LIBRARY_PREFIX')) {
+        return nameString;
       }
+      String libName = getName(lib);
+      // If a library name does not start with the [LIBRARY_PREFIX] then our
+      // assumptions about clashing with mangled private members do not hold.
+      assert(libName.startsWith(LIBRARY_PREFIX));
+      return '_$libName$nameString';
     } else {
-      result = name.slowToString();
+      return name.slowToString();
     }
-    return result;
   }
 
   String instanceMethodName(FunctionElement element) {
@@ -146,21 +120,20 @@ class Namer {
     FunctionSignature signature = element.computeSignature(compiler);
     String methodName =
         '${privateName(lib, name)}\$${signature.parameterCount}';
-    if (signature.optionalParametersAreNamed &&
-        !signature.optionalParameters.isEmpty) {
+    if (!signature.optionalParametersAreNamed) {
+      return methodName;
+    } else if (!signature.optionalParameters.isEmpty) {
       StringBuffer buffer = new StringBuffer();
       signature.orderedOptionalParameters.forEach((Element element) {
         buffer.add('\$${JsNames.getValid(element.name.slowToString())}');
       });
-      methodName = '$methodName$buffer';
+      return '$methodName$buffer';
     }
-    return getMappedInstanceName(methodName);
   }
 
   String publicInstanceMethodNameByArity(SourceString name, int arity) {
     assert(!name.isPrivate());
-    var proposedName = '${name.slowToString()}\$$arity';
-    return getMappedInstanceName(proposedName);
+    return '${name.slowToString()}\$$arity';
   }
 
   String instanceMethodInvocationName(LibraryElement lib, SourceString name,
@@ -172,13 +145,12 @@ class Namer {
       buffer.add(r'$');
       argumentName.printOn(buffer);
     }
-    return getMappedInstanceName(
-        '${privateName(lib, name)}\$${selector.argumentCount}$buffer');
+    return '${privateName(lib, name)}\$${selector.argumentCount}$buffer';
   }
 
   String instanceFieldName(LibraryElement libraryElement, SourceString name) {
     String proposedName = privateName(libraryElement, name);
-    return getMappedInstanceName(proposedName);
+    return safeName(proposedName);
   }
 
   String shadowedFieldName(Element fieldElement) {
@@ -187,64 +159,45 @@ class Namer {
     String libName = getName(libraryElement);
     String clsName = getName(cls);
     String instanceName = instanceFieldName(libraryElement, fieldElement.name);
-    return getMappedInstanceName('$libName\$$clsName\$$instanceName');
+    return safeName('$libName\$$clsName\$$instanceName');
   }
 
   String setterName(LibraryElement lib, SourceString name) {
     // We dynamically create setters from the field-name. The setter name must
     // therefore be derived from the instance field-name.
-    String fieldName = getMappedInstanceName(privateName(lib, name));
+    String fieldName = safeName(privateName(lib, name));
     return 'set\$$fieldName';
   }
 
   String publicGetterName(SourceString name) {
     // We dynamically create getters from the field-name. The getter name must
     // therefore be derived from the instance field-name.
-    String fieldName = getMappedInstanceName(name.slowToString());
+    String fieldName = safeName(name.slowToString());
     return 'get\$$fieldName';
   }
 
   String getterName(LibraryElement lib, SourceString name) {
     // We dynamically create getters from the field-name. The getter name must
     // therefore be derived from the instance field-name.
-    String fieldName = getMappedInstanceName(privateName(lib, name));
+    String fieldName = safeName(privateName(lib, name));
     return 'get\$$fieldName';
   }
 
-  String getMappedGlobalName(String proposedName) {
-    var newName = globalNameMap[proposedName];
-    if (newName == null) {
-      newName = getFreshName(proposedName, usedGlobalNames);
-      globalNameMap[proposedName] = newName;
+  String getFreshGlobalName(String proposedName) {
+    String name = proposedName;
+    int count = usedGlobals[name];
+    if (count != null) {
+      // Not the first time we see this name. Append a number to make it unique.
+      do {
+        name = '$proposedName${count++}';
+      } while (usedGlobals[name] != null);
+      // Record the count in case we see this name later. We
+      // frequently see names multiple times, as all our closures use
+      // the same name for their class.
+      usedGlobals[proposedName] = count;
     }
-    return newName;
-  }
-
-  String getMappedInstanceName(String proposedName) {
-    var newName = instanceNameMap[proposedName];
-    if (newName == null) {
-      newName = getFreshName(proposedName, usedInstanceNames);
-      instanceNameMap[proposedName] = newName;
-    }
-    return newName;
-  }
-
-  String getFreshName(String proposedName, Set<String> usedNames) {
-    var candidate;
-    proposedName = safeName(proposedName);
-    if (!usedNames.contains(proposedName)) {
-      candidate = proposedName;
-    } else {
-      var counter = popularNameCounters[proposedName];
-      var i = counter == null ? 0 : counter;
-      while (usedNames.contains("$proposedName$i")) {
-        i++;
-      }
-      popularNameCounters[proposedName] = i + 1;
-      candidate = "$proposedName$i";
-    }
-    usedNames.add(candidate);
-    return candidate;
+    usedGlobals[name] = 0;
+    return name;
   }
 
   static const String LIBRARY_PREFIX = "lib";
@@ -272,23 +225,17 @@ class Namer {
       } else {
         name = element.name.slowToString();
       }
-    } else if (element.isLibrary()) {
+    } else if (identical(element.kind, ElementKind.LIBRARY)) {
       name = LIBRARY_PREFIX;
     } else {
       name = element.name.slowToString();
     }
     // Prefix the name with '$' if it is reserved.
-    return name;
+    return safeName(name);
   }
 
   String getBailoutName(Element element) {
-    bool global = !element.isInstanceMember();
-    var unminifiedName = '${getName(element)}\$bailout';
-    if (global) {
-      return getMappedGlobalName(unminifiedName);
-    } else {
-      return getMappedInstanceName(unminifiedName);
-    }
+    return '${getName(element)}\$bailout';
   }
 
   /**
@@ -327,25 +274,17 @@ class Namer {
       if (identical(kind, ElementKind.VARIABLE) ||
           identical(kind, ElementKind.PARAMETER)) {
         // The name is not guaranteed to be unique.
-        return safeName(guess);
+        return guess;
       }
-      if (kind == ElementKind.GENERATIVE_CONSTRUCTOR ||
-          kind == ElementKind.FUNCTION ||
-          kind == ElementKind.CLASS ||
-          kind == ElementKind.FIELD ||
-          kind == ElementKind.GETTER ||
-          kind == ElementKind.SETTER ||
-          kind == ElementKind.TYPEDEF ||
-          kind == ElementKind.LIBRARY) {
-        bool isNative = false;
-        if (identical(kind, ElementKind.CLASS)) {
-          ClassElement class_elt = element;
-          isNative = class_elt.isNative();
-        }
-        if (Elements.isInstanceField(element)) {
-          isNative = element.isNative();
-        }
-        String result = isNative ? guess : getFreshName(guess, usedGlobalNames);
+      if (identical(kind, ElementKind.GENERATIVE_CONSTRUCTOR) ||
+          identical(kind, ElementKind.FUNCTION) ||
+          identical(kind, ElementKind.CLASS) ||
+          identical(kind, ElementKind.FIELD) ||
+          identical(kind, ElementKind.GETTER) ||
+          identical(kind, ElementKind.SETTER) ||
+          identical(kind, ElementKind.TYPEDEF) ||
+          identical(kind, ElementKind.LIBRARY)) {
+        String result = getFreshGlobalName(guess);
         globals[element] = result;
         return result;
       }
@@ -355,8 +294,9 @@ class Namer {
   }
 
   String getLazyInitializerName(Element element) {
+    // TODO(floitsch): mangle while not conflicting with other statics.
     assert(Elements.isStaticOrTopLevelField(element));
-    return getMappedGlobalName("get\$${getName(element)}");
+    return "get\$${getName(element)}";
   }
 
   String isolatePropertiesAccess(Element element) {
@@ -372,8 +312,7 @@ class Namer {
   }
 
   String isolateBailoutAccess(Element element) {
-    String newName = getMappedGlobalName('${getName(element)}\$bailout');
-    return '$CURRENT_ISOLATE.$newName';
+    return '${isolateAccess(element)}\$bailout';
   }
 
   String isolateLazyInitializerAccess(Element element) {
@@ -381,7 +320,6 @@ class Namer {
   }
 
   String operatorIs(Element element) {
-    // TODO(erikcorry): Reduce from is$x to ix when we are minifying.
     return 'is\$${getName(element)}';
   }