Bug 852478 - Store the date and time of downloads. r=paolo

toolkit/components/jsdownloads/src/DownloadCore.jsm

@@ -128,6 +128,13 @@ Download.prototype = {
    */
   error: null,
 
+  /**
+   * Indicates the start time of the download.  When the download starts,
+   * this property is set to a valid Date object.  The default value is null
+   * before the download starts.
+   */
+  startTime: null,
+
   /**
    * Indicates whether this download's "progress" property is able to report
    * partial progress while the download proceeds, and whether the value in
@@ -237,6 +244,7 @@ Download.prototype = {
     this.progress = 0;
     this.totalBytes = 0;
     this.currentBytes = 0;
+    this.startTime = new Date();
 
     // Create a new deferred object and an associated promise before starting
     // the actual download.  We store it on the download as the current attempt.

toolkit/components/jsdownloads/test/unit/head.js

@@ -127,6 +127,20 @@ function promiseExecuteSoon()
   return deferred.promise;
 }
 
+/**
+ * Waits for a pending events to be processed after a timeout.
+ *
+ * @return {Promise}
+ * @resolves When pending events have been processed.
+ * @rejects Never.
+ */
+function promiseTimeout(aTime)
+{
+  let deferred = Promise.defer();
+  do_timeout(aTime, deferred.resolve);
+  return deferred.promise;
+}
+
 /**
  * Creates a new Download object, setting a temporary file as the target.
  *
@@ -296,6 +310,16 @@ function registerInterruptibleHandler(aPath, aFirstPartFn, aSecondPartFn)
   });
 }
 
+/**
+ * Ensure the given date object is valid.
+ *
+ * @param aDate
+ *        The date object to be checked. This value can be null.
+ */
+function isValidDate(aDate) {
+  return aDate && aDate.getTime && !isNaN(aDate.getTime());
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 //// Initialization functions common to all tests
 

toolkit/components/jsdownloads/test/unit/test_DownloadCore.js

@@ -47,6 +47,7 @@ add_task(function test_download_initial_final_state()
   do_check_false(download.canceled);
   do_check_true(download.error === null);
   do_check_eq(download.progress, 0);
+  do_check_true(download.startTime === null);
 
   // Starts the download and waits for completion.
   yield download.start();
@@ -56,6 +57,7 @@ add_task(function test_download_initial_final_state()
   do_check_false(download.canceled);
   do_check_true(download.error === null);
   do_check_eq(download.progress, 100);
+  do_check_true(isValidDate(download.startTime));
 });
 
 /**
@@ -674,3 +676,25 @@ add_task(function test_download_error_restart()
 
   yield promiseVerifyContents(download.target.file, TEST_DATA_SHORT);
 });
+
+
+/**
+ * Checks the startTime gets updated even after a restart.
+ */
+add_task(function test_download_cancel_immediately_restart_and_check_startTime()
+{
+  let download = yield promiseSimpleDownload();
+
+  download.start();
+  let startTime = download.startTime;
+  do_check_true(isValidDate(download.startTime));
+
+  yield download.cancel();
+  do_check_eq(download.startTime.getTime(), startTime.getTime());
+
+  // Wait for a timeout.
+  yield promiseTimeout(10);
+
+  yield download.start();
+  do_check_true(download.startTime.getTime() > startTime.getTime());
+});