Code coverage, something is working now.

pkg/analyzer_experimental/bin/coverage.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 runtime.coverage;
 
-import "package:logging/logging.dart" as log;
+import 'dart:io';
 
-import 'package:analyzer_experimental/src/services/runtime/coverage_impl.dart';
+import 'package:args/args.dart' show ArgParser, ArgResults;
+
+import 'package:analyzer_experimental/src/services/runtime/log.dart' as log;
+import 'package:analyzer_experimental/src/services/runtime/coverage/coverage_impl.dart';
 
 
 main() {
-  var logger = log.Logger.root;
-  logger.level = log.Level.ALL;
-  logger.onRecord.listen((log.LogRecord record) {
-    String levelString = record.level.toString();
-    while (levelString.length < 6) levelString += ' ';
-    print('${record.time}: ${levelString} ${record.message}');
-  });
-  // TODO(scheglov) get script from options
-  new CoverageServer('/Users/scheglov/dart/Test/bin').start();
-}
+  ArgResults options;
+  try {
+    options = _argParser.parse(new Options().arguments);
+  } on FormatException catch (e) {
+    print(e.message);
+    print('Run "coverage --help" to see available options.');
+    exit(ERROR);
+  }
+
+  if (options['help']) {
+    printUsage();
+    return;
+  }
+
+  // No script to run.
+  if (options.rest.isEmpty) {
+    printUsage('<No script to run specified>');
+    exit(ERROR);
+  }
+
+  // More than one script specified.
+  if (options.rest.length != 1) {
+    print('<Only one script should be specified>');
+    exit(ERROR);
+  }
+
+  var scriptPath = options.rest[0];
+
+  // Validate that script file exists.
+  if (!new File(scriptPath).existsSync()) {
+    print('<File "$scriptPath" does not exist>');
+    exit(ERROR);
+  }
+
+  // Prepare output file path.
+  var outPath = options['out'];
+  if (outPath == null) {
+    printUsage('No --out specified.');
+    exit(ERROR);
+  }
+
+  // Configure logigng.
+  log.everything();
+  log.toConsole();
+
+  // Run script.
+  runServerApplication(scriptPath, outPath);
+}
+
+
+final ArgParser _argParser = new ArgParser()
+    ..addFlag('help', negatable: false, help: 'Print this usage information.')
+    ..addOption(
+        'level',
+        help: 'The level of the coverage.',
+        allowed: ['method', 'block', 'statement'],
+        defaultsTo: 'statement')
+    ..addOption('out', help: 'The output file with statistics.')
+    ..addOption(
+        'port',
+        help: 'The port to run server on, if 0 select any.',
+        defaultsTo: '0');
+
+
+printUsage([var description = 'Code coverage tool for Dart.']) {
+  var buffer = new StringBuffer();
+  var usage = _argParser.getUsage();
+  buffer.write(
+      '$description\n\n'
+      'Usage: coverage [options] <script>\n\n'
+      '$usage\n\n');
+  print(buffer.toString());
+}
+
+
+/// General error code.
+const ERROR = 1;