Update charted to 0.4.8 and roll

packages/watcher/benchmark/path_set.dart

+// Copyright (c) 2015, 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.
+
+/// Benchmarks for the PathSet class.
+library watcher.benchmark.path_set;
+
+import 'dart:io';
+import 'dart:math' as math;
+
+import 'package:benchmark_harness/benchmark_harness.dart';
+import 'package:path/path.dart' as p;
+
+import 'package:watcher/src/path_set.dart';
+
+final String root = Platform.isWindows ? r"C:\root" : "/root";
+
+/// Base class for benchmarks on [PathSet].
+abstract class PathSetBenchmark extends BenchmarkBase {
+  PathSetBenchmark(String method) : super("PathSet.$method");
+
+  final PathSet pathSet = new PathSet(root);
+
+  /// Use a fixed [Random] with a constant seed to ensure the tests are
+  /// deterministic.
+  final math.Random random = new math.Random(1234);
+
+  /// Walks over a virtual directory [depth] levels deep invoking [callback]
+  /// for each "file".
+  ///
+  /// Each virtual directory contains ten entries: either subdirectories or
+  /// files.
+  void walkTree(int depth, callback(String path)) {
+    recurse(path, remainingDepth) {
+      for (var i = 0; i < 10; i++) {
+        var padded = i.toString().padLeft(2, '0');
+        if (remainingDepth == 0) {
+          callback(p.join(path, "file_$padded.txt"));
+        } else {
+          var subdir = p.join(path, "subdirectory_$padded");
+          recurse(subdir, remainingDepth - 1);
+        }
+      }
+    }
+
+    recurse(root, depth);
+  }
+}
+
+class AddBenchmark extends PathSetBenchmark {
+  AddBenchmark() : super("add()");
+
+  final List<String> paths = [];
+
+  void setup() {
+    // Make a bunch of paths in about the same order we expect to get them from
+    // Directory.list().
+    walkTree(3, paths.add);
+  }
+
+  void run() {
+    for (var path in paths) pathSet.add(path);
+  }
+}
+
+class ContainsBenchmark extends PathSetBenchmark {
+  ContainsBenchmark() : super("contains()");
+
+  final List<String> paths = [];
+
+  void setup() {
+    // Add a bunch of paths to the set.
+    walkTree(3, (path) {
+      pathSet.add(path);
+      paths.add(path);
+    });
+
+    // Add some non-existent paths to test the false case.
+    for (var i = 0; i < 100; i++) {
+      paths.addAll([
+        "/nope",
+        "/root/nope",
+        "/root/subdirectory_04/nope",
+        "/root/subdirectory_04/subdirectory_04/nope",
+        "/root/subdirectory_04/subdirectory_04/subdirectory_04/nope",
+        "/root/subdirectory_04/subdirectory_04/subdirectory_04/nope/file_04.txt",
+      ]);
+    }
+  }
+
+  void run() {
+    var contained = 0;
+    for (var path in paths) {
+      if (pathSet.contains(path)) contained++;
+    }
+
+    if (contained != 10000) throw "Wrong result: $contained";
+  }
+}
+
+class PathsBenchmark extends PathSetBenchmark {
+  PathsBenchmark() : super("toSet()");
+
+  void setup() {
+    walkTree(3, pathSet.add);
+  }
+
+  void run() {
+    var count = 0;
+    for (var _ in pathSet.paths) {
+      count++;
+    }
+
+    if (count != 10000) throw "Wrong result: $count";
+  }
+}
+
+class RemoveBenchmark extends PathSetBenchmark {
+  RemoveBenchmark() : super("remove()");
+
+  final List<String> paths = [];
+
+  void setup() {
+    // Make a bunch of paths. Do this here so that we don't spend benchmarked
+    // time synthesizing paths.
+    walkTree(3, (path) {
+      pathSet.add(path);
+      paths.add(path);
+    });
+
+    // Shuffle the paths so that we delete them in a random order that
+    // hopefully mimics real-world file system usage. Do the shuffling here so
+    // that we don't spend benchmarked time shuffling.
+    paths.shuffle(random);
+  }
+
+  void run() {
+    for (var path in paths) pathSet.remove(path);
+  }
+}
+
+main() {
+  new AddBenchmark().report();
+  new ContainsBenchmark().report();
+  new PathsBenchmark().report();
+  new RemoveBenchmark().report();
+}