Setting up benchmarks and perf utilities

test/perf/update.dart

+#!/usr/bin/env dart

[Jennifer Messerly, 2013/01/07 21:07:46]

rename this script to update_json or copy_json?

[Siggi Cherem (dart-lang), 2013/01/08 02:26:18]

Done.

+// 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.
+
+/**
+ * A simple script that updates a target json file with the new values from

[Jennifer Messerly, 2013/01/07 21:07:46]

I might've missed where this is called from?

[Siggi Cherem (dart-lang), 2013/01/08 02:26:18]

nowhere - it's an utility script used from the command line to help with our
workflow.

+ * another json file.
+ */

[Jennifer Messerly, 2013/01/07 21:07:46]

library tag, so this comment has something to be attached to?

[Siggi Cherem (dart-lang), 2013/01/08 02:26:18]

Done.

+
+import 'dart:io';
+import 'dart:json';
+import 'dart:math' as math;
+
+main() {
+  var args = new Options().arguments;
+  if (args.length < 2) {
+    print('usage: update.dart from.json to.json');

[Jennifer Messerly, 2013/01/07 21:07:46]

Would be nice to print the nice library comment here.

[Siggi Cherem (dart-lang), 2013/01/08 02:26:18]

Done.

+    exit(1);
+  }
+
+  var path1 = args[0];
+  var path2 = args[1];
+  var file1 = new File(path1).readAsStringSync();
+  var file2 = new File(path2).readAsStringSync();
+
+  var results = [];
+  var map1 = JSON.parse(file1);
+  var map2 = JSON.parse(file2);
+
+  for (var key in map1.keys) {
+    if (map1[key] != null) {
+      map2[key] = map1[key];
+    }
+  }
+
+  print('updating $path2...');
+  _writeFile(path2, JSON.stringify(map2));
+}
+
+Future _writeFile(String path, String text) {
+  return new File(path).open(FileMode.WRITE)
+      .chain((file) => file.writeString(text))
+      .chain((file) => file.close());
+}