Improve hot reload test mode

tools/testing/dart/multitest.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.
 
 library multitest;
 
 import "dart:async";
 import "dart:io";
 
 import "path.dart";
@@ skipping 203 matching lines @@
           foundImports.add(relativePath.toString());
           toSearch.add(libraryDir.join(relativePath));
         }
       }
     }
   }
   return foundImports;
 }
 
 Future doMultitest(
-    Path filePath, String outputDir, Path suiteDir, CreateTest doTest) {
+    Path filePath,
+    String outputDir,
+    Path suiteDir,
+    CreateTest doTest,
+    bool hotReload) {
   void writeFile(String filepath, String content) {
     final File file = new File(filepath);
 
     if (file.existsSync()) {
       var oldContent = file.readAsStringSync();
       if (oldContent == content) {
         // Don't write to the file if the content is the same
         return;
       }
     }
@@ skipping 31 matching lines @@
       final Path multitestFilename =
           targetDir.append('${baseFilename}_$key.dart');
       writeFile(multitestFilename.toNativePath(), tests[key]);
       Set<String> outcome = outcomes[key];
       bool hasStaticWarning = outcome.contains('static type warning');
       bool hasRuntimeErrors = outcome.contains('runtime error');
       bool hasCompileError = outcome.contains('compile-time error');
       bool isNegativeIfChecked = outcome.contains('dynamic type error');
       bool hasCompileErrorIfChecked =
           outcome.contains('checked mode compile-time error');
+      if (hotReload) {
+        if (hasCompileError || hasCompileErrorIfChecked) {
+          // Running a test that expects a compilation error with hot reloading
+          // is redundant with a regular run of the test.
+          continue;
+        }
+      }
       doTest(multitestFilename, filePath, hasCompileError, hasRuntimeErrors,
           isNegativeIfChecked: isNegativeIfChecked,
           hasCompileErrorIfChecked: hasCompileErrorIfChecked,
           hasStaticWarning: hasStaticWarning,
           multitestKey: key);
     }
 
     return null;
   });
 }
@@ skipping 12 matching lines @@
     // TestSuite.forDirectory.
     split.removeLast();
   }
   String path = '${generatedTestDir.path}/${split.last}';
   Directory dir = new Directory(path);
   if (!dir.existsSync()) {
     dir.createSync();
   }
   return new Path(new File(path).absolute.path);
 }