anchor.diff:      var relativePath = path.relative(testFile, from: codegenTestDir);
   
       // Only compile the top-level files for generating coverage.
  -    if (codeCoverage && path.dirname(relativePath) != ".") continue;
  +    bool isTopLevelTest = path.dirname(relativePath) == ".";
  +    if (codeCoverage && !isTopLevelTest) continue;
   
       var name = path.withoutExtension(relativePath);
       test('dartdevc $name', () {
  -      var relativeDir = path.dirname(relativePath);
  -      var outDir = path.join(codegenOutputDir, relativeDir);
  -      var expectDir = path.join(codegenExpectDir, relativeDir);
  -
         // Check if we need to use special compile options.
         var contents = new File(testFile).readAsStringSync();
         var match =
  
positive.code: 
    var jsFile = new File(outPath + '.js');
    var summaryFile = new File(outPath + '.sum');
    var expectFile = new File(expectPath + '.js');
    var errorFile = new File(outPath + '.err');
  
    if (result.isValid) {
  
negative.code:       new File(mapPath)
            .writeAsStringSync(JSON.encode(result.placeSourceMap(mapPath)));
      }
  
      // There are no errors, so delete any stale ".err" file.
      if (errorFile.existsSync()) {
  