Clean up handling of types.

lib/compiler/implementation/compiler.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.
 
 class WorkItem {
   final Element element;
   TreeElements resolutionTree;
   Function run;
   bool allowSpeculativeOptimization = true;
   List<HTypeGuard> guards = const <HTypeGuard>[];
@@ skipping 17 matching lines @@
   String codegen(Compiler compiler) {
     return compiler.codegen(this);
   }
 }
 
 class Compiler implements DiagnosticListener {
   Queue<WorkItem> worklist;
   Universe universe;
   String assembledCode;
   Namer namer;
-  final Types types;
+  Types types;
 
   final Tracer tracer;
 
   CompilerTask measuredTask;
   Element _currentElement;
   LibraryElement coreLibrary;
   LibraryElement coreImplLibrary;
   LibraryElement isolateLibrary;
   LibraryElement jsHelperLibrary;
   LibraryElement mainApp;
@@ skipping 40 matching lines @@
       const SourceString('NoSuchMethodException');
   static final SourceString START_ROOT_ISOLATE =
       const SourceString('startRootIsolate');
   bool enabledNoSuchMethod = false;
 
   bool workListIsClosed = false;
 
   Stopwatch codegenProgress;
 
   Compiler([this.tracer = const Tracer()])
-      : types = new Types(),
-        universe = new Universe(),
+      : universe = new Universe(),
         worklist = new Queue<WorkItem>(),
         codegenProgress = new Stopwatch.start() {
     namer = new Namer(this);
     constantHandler = new ConstantHandler(this);
     scanner = new ScannerTask(this);
     dietParser = new DietParserTask(this);
     parser = new ParserTask(this);
     validator = new TreeValidatorTask(this);
     resolver = new ResolverTask(this);
     checker = new TypeCheckerTask(this);
@@ skipping 95 matching lines @@
       // and see Dynamic this way.
       withCurrentElement(dynamicClass, () {
         library.define(dynamicClass, this);
       });
     }
   }
 
   abstract LibraryElement scanBuiltinLibrary(String filename);
 
   void initializeSpecialClasses() {
-    objectClass = coreLibrary.find(const SourceString('Object'));
-    boolClass = coreLibrary.find(const SourceString('bool'));
-    numClass = coreLibrary.find(const SourceString('num'));
-    intClass = coreLibrary.find(const SourceString('int'));
-    doubleClass = coreLibrary.find(const SourceString('double'));
-    stringClass = coreLibrary.find(const SourceString('String'));
-    functionClass = coreLibrary.find(const SourceString('Function'));
-    listClass = coreLibrary.find(const SourceString('List'));
-    closureClass = jsHelperLibrary.find(const SourceString('Closure'));
-    dynamicClass = types.dynamicType.element;
-    nullClass = jsHelperLibrary.find(const SourceString('Null'));
+    bool coreLibValid = true;
+    ClassElement lookupSpecialClass(SourceString name) {
+      ClassElement result = coreLibrary.find(name);
+      if (result === null) {
+        log('core library class $name missing');
+        coreLibValid = false;
+      }
+      return result;
+    }
+    objectClass = lookupSpecialClass(const SourceString('Object'));
+    boolClass = lookupSpecialClass(const SourceString('bool'));
+    numClass = lookupSpecialClass(const SourceString('num'));
+    intClass = lookupSpecialClass(const SourceString('int'));
+    doubleClass = lookupSpecialClass(const SourceString('double'));
+    stringClass = lookupSpecialClass(const SourceString('String'));
+    functionClass = lookupSpecialClass(const SourceString('Function'));
+    listClass = lookupSpecialClass(const SourceString('List'));
+    closureClass = lookupSpecialClass(const SourceString('Closure'));
+    dynamicClass = lookupSpecialClass(const SourceString('Dynamic'));
+    nullClass = lookupSpecialClass(const SourceString('Null'));
+    types = new Types(dynamicClass);
+    if (!coreLibValid) {
+      cancel('core library does not contain required classes');
+    }
   }
 
   void scanBuiltinLibraries() {
     coreImplLibrary = scanBuiltinLibrary('coreimpl');
     jsHelperLibrary = scanBuiltinLibrary('_js_helper');
     coreLibrary = scanBuiltinLibrary('core');
 
     // Since coreLibrary import the libraries "coreimpl", and
     // "js_helper", coreLibrary is null when they are being built. So
     // we add the implicit import of coreLibrary now. This can be
@@ skipping 302 matching lines @@
   }
 }
 
 class SourceSpan {
   final Uri uri;
   final int begin;
   final int end;
 
   const SourceSpan(this.uri, this.begin, this.end);
 }