[fsp] Simplify browser tests by extracting the common code.

chrome/test/data/extensions/api_test/file_system_provider/read_directory/test.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.
 
 'use strict';
 
 /**
  * @type {DOMFileSystem}
  */
 var fileSystem = null;
 
 /**
- * @type {string}
- * @const
- */
-var FILE_SYSTEM_ID = 'vanilla';
-
-/**
  * @type {Object}
  * @const
  */
 var TESTING_ROOT = Object.freeze({
   isDirectory: true,
   name: '',
   size: 0,
   modificationTime: new Date(2014, 4, 28, 10, 39, 15)
 });
 
@@ skipping 24 matching lines @@
  * @const
  */
 var TESTING_TIRAMISU_FILE = Object.freeze({
   isDirectory: false,
   name: 'tiramisu.txt',
   size: 1986,
   modificationTime: new Date(2014, 1, 25, 7, 36, 12)
 });
 
 /**
- * Gets volume information for the provided file system.
- *
- * @param {string} fileSystemId Id of the provided file system.
- * @param {function(Object)} callback Callback to be called on result, with the
- *     volume information object in case of success, or null if not found.
- */
-function getVolumeInfo(fileSystemId, callback) {
-  chrome.fileBrowserPrivate.getVolumeMetadataList(function(volumeList) {
-    for (var i = 0; i < volumeList.length; i++) {
-      if (volumeList[i].extensionId == chrome.runtime.id &&
-          volumeList[i].fileSystemId == fileSystemId) {
-        callback(volumeList[i]);
-        return;
-      }
-    }
-    callback(null);
-  });
-}
-
-/**
  * Returns entries in the requested directory.
  *
  * @param {ReadDirectoryRequestedOptions} options Options.
  * @param {function(Array.<Object>, boolean)} onSuccess Success callback with
  *     a list of entries. May be called multiple times.
  * @param {function(string)} onError Error callback with an error code.
  */
 function onReadDirectoryRequested(options, onSuccess, onError) {
-  if (options.fileSystemId != FILE_SYSTEM_ID) {
+  if (options.fileSystemId != test_util.FILE_SYSTEM_ID) {
     onError('SECURITY');  // enum ProviderError.
     return;
   }
 
   if (options.directoryPath != '/' + TESTING_HELLO_DIR.name) {
     onError('NOT_FOUND');  // enum ProviderError.
     return;
   }
 
   onSuccess([TESTING_TIRAMISU_FILE], true /* hasMore */);
   onSuccess([TESTING_CANDIES_DIR], false /* hasMore */);
 }
 
 /**
  * Returns metadata for the requested entry.
  *
  * To successfully acquire a DirectoryEntry, or even a DOMFileSystem, this event
  * must be implemented and return correct values.
  *
  * @param {GetMetadataRequestedOptions} options Options.
  * @param {function(Object)} onSuccess Success callback with metadata passed
  *     an argument.
  * @param {function(string)} onError Error callback with an error code.
  */
 function onGetMetadataRequested(options, onSuccess, onError) {
-  if (options.fileSystemId != FILE_SYSTEM_ID) {
+  if (options.fileSystemId != test_util.FILE_SYSTEM_ID) {
     onError('SECURITY');  // enum ProviderError.
     return;
   }
 
   if (options.entryPath == '/') {
     onSuccess(TESTING_ROOT);
     return;
   }
 
   if (options.entryPath == '/' + TESTING_HELLO_DIR.name) {
     onSuccess(TESTING_HELLO_DIR);
     return;
   }
 
   onError('NOT_FOUND');  // enum ProviderError.
 }
 
 /**
  * Sets up the tests. Called once per all test cases. In case of a failure,
  * the callback is not called.
  *
  * @param {function()} callback Success callback.
  */
 function setUp(callback) {
-  chrome.fileSystemProvider.mount(
-      {
-        fileSystemId: FILE_SYSTEM_ID,
-        displayName: 'chocolate.zip'
-      },
-      function() {
-        chrome.fileSystemProvider.onReadDirectoryRequested.addListener(
-            onReadDirectoryRequested);
-        chrome.fileSystemProvider.onGetMetadataRequested.addListener(
-            onGetMetadataRequested);
-        getVolumeInfo(FILE_SYSTEM_ID, function(volumeInfo) {
-          chrome.test.assertTrue(!!volumeInfo);
-          chrome.fileBrowserPrivate.requestFileSystem(
-              volumeInfo.volumeId,
-              function(inFileSystem) {
-                chrome.test.assertTrue(!!inFileSystem);
-
-                fileSystem = inFileSystem;
-                callback();
-              });
-        });
-      },
-      function() {
-        chrome.test.fail();
-      });
+  chrome.fileSystemProvider.onGetMetadataRequested.addListener(
+      onGetMetadataRequested);
+  chrome.fileSystemProvider.onReadDirectoryRequested.addListener(
+      onReadDirectoryRequested);
+  test_util.mountFileSystem(callback);
 }
 
 /**
  * Runs all of the test cases, one by one.
  */
 function runTests() {
   chrome.test.runTests([
     // Read contents of the /hello directory. This directory exists, so it
     // should succeed.
     function readEntriesSuccess() {
       var onTestSuccess = chrome.test.callbackPass();
-      fileSystem.root.getDirectory(
+      test_util.fileSystem.root.getDirectory(
           'hello',
           {create: false},
           function(dirEntry) {
             var dirReader = dirEntry.createReader();
             var entries = [];
             var readEntriesNext = function() {
               dirReader.readEntries(function(inEntries) {
                 Array.prototype.push.apply(entries, inEntries);
                 if (!inEntries.length) {
                   // No more entries, so verify.
@@ skipping 16 matching lines @@
             readEntriesNext();
           },
           function(error) {
             chrome.test.fail();
           });
     },
     // Read contents of a directory which does not exist, what should return an
     // error.
     function readEntriesError() {
       var onTestSuccess = chrome.test.callbackPass();
-      fileSystem.root.getDirectory(
+      test_util.fileSystem.root.getDirectory(
           'cranberries',
           {create: false},
           function(dirEntry) {
             chrome.test.fail();
           },
           function(error) {
             chrome.test.assertEq('NotFoundError', error.name);
             onTestSuccess();
           });
     }
   ]);
 }
 
 // Setup and run all of the test cases.
 setUp(runTests);