Check that non-abstract classes implement all methods.

dart/tests/compiler/dart2js/memory_compiler.dart

 // Copyright (c) 2013, 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.
 
 library dart2js.test.memory_compiler;
 
 import 'package:expect/expect.dart';
 import 'memory_source_file_helper.dart';
 
 import '../../../sdk/lib/_internal/compiler/implementation/dart2jslib.dart'
@@ skipping 56 matching lines @@
         diagnosticHandler(uri, begin, end, message, kind);
         formattingHandler(uri, begin, end, message, kind);
       };
     }
   } else if (diagnosticHandler == null) {
     handler = (Uri uri, int begin, int end, String message, Diagnostic kind) {};
   }
   return handler;
 }
 
+Expando<MemorySourceFileProvider> expando =
+    new Expando<MemorySourceFileProvider>();
+
 Compiler compilerFor(Map<String,String> memorySourceFiles,
                      {DiagnosticHandler diagnosticHandler,
                       List<String> options: const [],
                       Compiler cachedCompiler,
                       bool showDiagnostics: true}) {
   Uri script = currentDirectory.resolveUri(Platform.script);
   Uri libraryRoot = script.resolve('../../../sdk/');
   Uri packageRoot = script.resolve('./packages/');
 
-  var provider = new MemorySourceFileProvider(memorySourceFiles);
+  MemorySourceFileProvider provider;
+  var readStringFromUri;
+  if (cachedCompiler == null) {
+    provider = new MemorySourceFileProvider(memorySourceFiles);
+    readStringFromUri = provider.readStringFromUri;
+    // Saving the provider in case we need it later for a cached compiler.
+    expando[readStringFromUri] = provider;
+  } else {
+    // When using a cached compiler, it has read a number of files from disk
+    // already (and will not attemp to read them again due to caching). These
+    // files must be available to the new diagnostic handler.
+    provider = expando[cachedCompiler.provider];
+    readStringFromUri = cachedCompiler.provider;
+    provider.memorySourceFiles.clear();
+    memorySourceFiles.forEach((key, value) {
+      provider.memorySourceFiles[key] = value;
+    });
+  }
   var handler =
       createDiagnosticHandler(diagnosticHandler, provider, showDiagnostics);
 
   EventSink<String> outputProvider(String name, String extension) {
     if (name != '') throw 'Attempt to output file "$name.$extension"';
     return new NullSink('$name.$extension');
   }
 
-  Compiler compiler = new Compiler(provider.readStringFromUri,
+  Compiler compiler = new Compiler(readStringFromUri,
                                    outputProvider,
                                    handler,
                                    libraryRoot,
                                    packageRoot,
                                    options,
                                    {});
   if (cachedCompiler != null) {
     compiler.coreLibrary = cachedCompiler.libraries['dart:core'];
     compiler.types = cachedCompiler.types;
     cachedCompiler.libraries.forEach((String uri, library) {
@@ skipping 40 matching lines @@
       createDiagnosticHandler(diagnosticHandler, provider, showDiagnostics);
 
   List<Uri> libraries = <Uri>[];
   memorySourceFiles.forEach((String path, _) {
     libraries.add(new Uri(scheme: 'memory', path: path));
   });
 
   return analyze(libraries, libraryRoot, packageRoot,
                  provider, handler, options);
 }