Recover from read errors.

dart/tests/compiler/dart2js/missing_file_test.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.
 
 // Test that the compiler can handle imports when package root has not been set.
 
 library dart2js.test.missing_file;
 
 import 'package:expect/expect.dart';
 import "package:async_helper/async_helper.dart";
 import 'memory_source_file_helper.dart';
 
 import 'package:compiler/src/dart2jslib.dart'
        show NullSink;
 
 import 'package:compiler/compiler.dart'
        show DiagnosticHandler, Diagnostic;
 
 import 'dart:async';
 
 const MEMORY_SOURCE_FILES = const {
   'main.dart': '''
 
 import 'foo.dart';
 
 main() {}
 ''',
 };
 
-void runCompiler(Uri main, String expectedMessage) {
+Future runCompiler(Uri main, String expectedMessage) {
+  print("\n\n\n");
   Uri script = currentDirectory.resolveUri(Platform.script);
   Uri libraryRoot = script.resolve('../../../sdk/');
   Uri packageRoot = script.resolve('./packages/');
 
   var provider = new MemorySourceFileProvider(MEMORY_SOURCE_FILES);
   var handler = new FormattingDiagnosticHandler(provider);
   var errors = [];
 
   void diagnosticHandler(Uri uri, int begin, int end, String message,
                          Diagnostic kind) {
@@ skipping 10 matching lines @@
   }
 
   Compiler compiler = new Compiler(provider,
                                    outputProvider,
                                    diagnosticHandler,
                                    libraryRoot,
                                    packageRoot,
                                    [],
                                    {});
 
-  asyncTest(() => compiler.run(main).then((_) {
+  return compiler.run(main).then((_) {
     Expect.equals(1, errors.length);
     Expect.equals(expectedMessage,
                   errors[0]);
-  }));
+  });
 }
 
 void main() {
-  runCompiler(Uri.parse('memory:main.dart'),
-              "Can't read 'memory:foo.dart' "
-              "(Exception: No such file memory:foo.dart).");
-  runCompiler(Uri.parse('memory:foo.dart'),
-              "Can't read 'memory:foo.dart' "
-              "(Exception: No such file memory:foo.dart).");
-  runCompiler(Uri.parse('dart:foo'),
-              "Library not found 'dart:foo'.");
+  asyncTest(() => Future.forEach([
+  () => runCompiler(
+      Uri.parse('memory:main.dart'),
+      "Can't read 'memory:foo.dart' "
+      "(Exception: No such file memory:foo.dart)."),
+  () => runCompiler(
+      Uri.parse('memory:foo.dart'),
+      "Exception: No such file memory:foo.dart"),
+  () => runCompiler(
+      Uri.parse('dart:foo'),
+      "Library not found 'dart:foo'."),
+  ], (f) => f()));
 }