Files.app: Create unit tests for MetadataCache.

BUG=386553 TEST=run the test Review URL: https://codereview.chromium.org/340843005 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278736 0039d316-1c4b-4281-b951-d872f2087c98

Files.app: Create unit tests for MetadataCache.
BUG=386553 TEST=run the test Review URL: https://codereview.chromium.org/340843005 git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278736 0039d316-1c4b-4281-b951-d872f2087c98
025ed709 · hirono@chromium.org · 80bfae11 · 025ed709 · 025ed709 · 025ed709
Commit 025ed709 authored Jun 20, 2014 by hirono@chromium.org
5 changed files
--- a/chrome/browser/chromeos/file_manager/file_manager_jstest.cc
+++ b/chrome/browser/chromeos/file_manager/file_manager_jstest.cc
@@ -48,6 +48,10 @@ IN_PROC_BROWSER_TEST_F(

 IN_PROC_BROWSER_TEST_F(
    FileManagerJsTest, DeviceHandlerTest) {
-  RunTest(base::FilePath(
-      FILE_PATH_LITERAL("device_handler_unittest.html")));
+  RunTest(base::FilePath(FILE_PATH_LITERAL("device_handler_unittest.html")));
+}
+
+IN_PROC_BROWSER_TEST_F(
+    FileManagerJsTest, MetadataCacheTest) {
+  RunTest(base::FilePath(FILE_PATH_LITERAL("metadata_cache_unittest.html")));
 }
--- a/chrome/test/data/file_manager/unit_tests/metadata_cache_unittest.html
+++ b/chrome/test/data/file_manager/unit_tests/metadata_cache_unittest.html
+<!DOCTYPE html>
+<!-- Copyright 2014 The Chromium Authors. All rights reserved.
+  -- Use of this source code is governed by a BSD-style license that can be
+  -- found in the LICENSE file.
+  -->
+
+<html>
+<body>
+
+<script src="../../../../../ui/file_manager/file_manager/foreground/js/metadata/metadata_cache.js"></script>
+<script src="mocks/mock_file_entry.js"></script>
+
+<script src="metadata_cache_unittest.js"></script>
+
+</body>
+</html>
--- a/chrome/test/data/file_manager/unit_tests/metadata_cache_unittest.js
+++ b/chrome/test/data/file_manager/unit_tests/metadata_cache_unittest.js
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var metadataCache;
+var provider;
+
+/**
+ * Mock of MetadataProvider.
+ * @constructor
+ */
+function MockProvider() {
+  MetadataProvider.call(this);
+  this.callbackPool = [];
+  Object.freeze(this);
+}
+
+MockProvider.prototype = {
+  __proto__: MetadataProvider.prototype
+};
+
+MockProvider.prototype.supportsEntry = function(entry) {
+  return true;
+};
+
+MockProvider.prototype.providesType = function(type) {
+  return type === 'stub';
+};
+
+MockProvider.prototype.getId = function() {
+  return 'stub';
+};
+
+MockProvider.prototype.fetch = function(entry, type, callback) {
+  this.callbackPool.push(callback);
+};
+
+/**
+ * Short hand for the metadataCache.get.
+ *
+ * @param {Array.<Entry>} entries Entries.
+ * @param {string} type Metadata type.
+ * @return {Promise} Promise to be fulfilled with the result metadata.
+ */
+function getMetadata(entries, type) {
+  return new Promise(metadataCache.get.bind(metadataCache, entries, type));
+};
+
+/**
+ * Invokes a callback function depending on the result of promise.
+ *
+ * @param {Promise} promise Promise.
+ * @param {function(boolean)} calllback Callback function. True is passed if the
+ * test failed.
+ */
+function reportPromise(promise, callback) {
+  promise.then(function() {
+    callback(/* error */ false);
+  }, function(error) {
+    console.error(error.stack || error);
+    callback(/* error */ true);
+  });
+}
+
+/**
+ * Constructs the metadata cache and its provider.
+ */
+function setUp() {
+  provider = new MockProvider();
+  metadataCache = new MetadataCache([provider]);
+}
+
+/**
+ * Confirms metadata is cached for the same entry.
+ *
+ * @param {function(boolean=)} callback Callback to be called when test
+ *     completes. If the test fails, true is passed to the function.
+ */
+function testCached(callback) {
+  var entry = new MockFileEntry('volumeId', '/banjo.txt');
+
+  var promises = [];
+  var firstPromise = getMetadata([entry], 'stub');
+  var cachedBeforeFetchingPromise =  getMetadata([entry], 'stub');
+  provider.callbackPool[0]({stub: {value: 'banjo'}});
+  var cachedAfterFethingPromise = getMetadata([entry], 'stub');
+
+  // Provide should be called only once.
+  assertEquals(1, provider.callbackPool.length);
+
+  reportPromise(Promise.all([
+    firstPromise,
+    cachedBeforeFetchingPromise,
+    cachedAfterFethingPromise
+  ]).then(function(metadata) {
+    assertDeepEquals([{value: 'banjo'}], metadata[0]);
+    assertDeepEquals([{value: 'banjo'}], metadata[1]);
+    assertDeepEquals([{value: 'banjo'}], metadata[1]);
+  }), callback);
+}
+
+/**
+ * Confirms metadata is not cached for different entries.
+ *
+ * @param {function(boolean=)} callback Callback to be called when test
+ *     completes. If the test fails, true is passed to the function.
+ */
+function testNotCached(callback) {
+  var entry1 = new MockFileEntry('volumeId', '/banjo.txt');
+  var entry2 = new MockFileEntry('volumeId', '/fiddle.txt');
+
+  var firstPromise = getMetadata([entry1], 'stub');
+  var anotherPromise = getMetadata([entry2], 'stub');
+
+  // Provide should be called for each entry.
+  assertEquals(2, provider.callbackPool.length);
+
+  provider.callbackPool[0]({stub: {value: 'banjo'}});
+  provider.callbackPool[1]({stub: {value: 'fiddle'}});
+
+  reportPromise(Promise.all([
+    firstPromise,
+    anotherPromise
+  ]).then(function(metadata) {
+    assertDeepEquals([{value: 'banjo'}], metadata[0]);
+    assertDeepEquals([{value: 'fiddle'}], metadata[1]);
+  }), callback);
+}
--- a/chrome/test/data/file_manager/unit_tests/mocks/mock_file_entry.js
+++ b/chrome/test/data/file_manager/unit_tests/mocks/mock_file_entry.js
@@ -13,3 +13,12 @@ function MockFileEntry(volumeId, fullPath) {
  this.volumeId = volumeId;
  this.fullPath = fullPath;
 }
+
+/**
+ * Returns fake URL.
+ *
+ * @return {string} Fake URL.
+ */
+MockFileEntry.prototype.toURL = function() {
+  return 'filesystem:' + this.volumeId + this.fullPath;
+};
--- a/ui/file_manager/file_manager/foreground/js/metadata/metadata_cache.js
+++ b/ui/file_manager/file_manager/foreground/js/metadata/metadata_cache.js
@@ -46,9 +46,10 @@
 *   var size = (cached && cached.size) || UNKNOWN_SIZE;
 * }
 *
+ * @param {Array.<MetadataProvider>} providers Metadata providers.
 * @constructor
 */
-function MetadataCache() {
+function MetadataCache(providers) {
  /**
   * Map from Entry (using Entry.toURL) to metadata. Metadata contains
   * |properties| - an hierarchical object of values, and an object for each
@@ -61,7 +62,7 @@ function MetadataCache() {
   * List of metadata providers.
   * @private
   */
-  this.providers_ = [];
+  this.providers_ = providers;

  /**
   * List of observers added. Each one is an object with fields:
@@ -81,9 +82,13 @@ function MetadataCache() {
  /**
   * Time of first get query of the current batch. Items updated later than this
   * will not be evicted.
+   *
+   * @type {Date}
   * @private
   */
  this.lastBatchStart_ = new Date();
+
+  Object.seal(this);
 }

 /**
@@ -114,13 +119,13 @@ MetadataCache.EVICTION_THRESHOLD_MARGIN = 500;
 * @return {MetadataCache!} The cache with all providers.
 */
 MetadataCache.createFull = function(volumeManager) {
-  var cache = new MetadataCache();
  // DriveProvider should be prior to FileSystemProvider, because it covers
  // FileSystemProvider for files in Drive.
-  cache.providers_.push(new DriveProvider(volumeManager));
-  cache.providers_.push(new FilesystemProvider());
-  cache.providers_.push(new ContentProvider());
-  return cache;
+  return new MetadataCache([
+    new DriveProvider(volumeManager),
+    new FilesystemProvider(),
+    new ContentProvider()
+  ]);
 };

 /**