From 1a9b300cbb6c7bd91c392f35a1eaadf811c5ec10 Mon Sep 17 00:00:00 2001
From: Tomislav Jovanovic <tomica@gmail.com>
Date: Thu, 29 Mar 2018 20:09:45 +0200
Subject: [PATCH] Bug 1418616 - Add default extension to downloads saveAs
 dialogs, r=rpl

MozReview-Commit-ID: 9WOfZoc7wa6

--HG--
extra : rebase_source : c9c91002be76f37dc80132f92e9b11e11f4ab4e9
---
 toolkit/components/extensions/parent/ext-downloads.js     | 10 ++++++++--
 .../test/mochitest/test_chrome_ext_downloads_saveAs.html  | 15 ++++++++++-----
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/toolkit/components/extensions/parent/ext-downloads.js b/toolkit/components/extensions/parent/ext-downloads.js
index 2d9cf20bd0a2..a08d089e7808 100644
--- a/toolkit/components/extensions/parent/ext-downloads.js
+++ b/toolkit/components/extensions/parent/ext-downloads.js
@@ -519,13 +519,19 @@ this.downloads = class extends ExtensionAPI {
               return target;
             }
 
+            const window = Services.wm.getMostRecentWindow("navigator:browser");
+            const basename = OS.Path.basename(target);
+            const ext = basename.match(/\.([^.]+)$/);
+
             // Setup the file picker Save As dialog.
             const picker = Cc["@mozilla.org/filepicker;1"].createInstance(Ci.nsIFilePicker);
-            const window = Services.wm.getMostRecentWindow("navigator:browser");
             picker.init(window, null, Ci.nsIFilePicker.modeSave);
             picker.displayDirectory = new FileUtils.File(dir);
             picker.appendFilters(Ci.nsIFilePicker.filterAll);
-            picker.defaultString = OS.Path.basename(target);
+            picker.defaultString = basename;
+
+            // Configure a default file extension, used as fallback on Windows.
+            picker.defaultExtension = ext && ext[1];
 
             // Open the dialog and resolve/reject with the result.
             return new Promise((resolve, reject) => {
diff --git a/toolkit/components/extensions/test/mochitest/test_chrome_ext_downloads_saveAs.html b/toolkit/components/extensions/test/mochitest/test_chrome_ext_downloads_saveAs.html
index d583bb698fdd..5bee14695c6b 100644
--- a/toolkit/components/extensions/test/mochitest/test_chrome_ext_downloads_saveAs.html
+++ b/toolkit/components/extensions/test/mochitest/test_chrome_ext_downloads_saveAs.html
@@ -49,10 +49,10 @@ add_task(async function setup() {
 
 add_task(async function test_downloads_saveAs() {
   const pickerFile = pickerDir.clone();
-  pickerFile.append("file_download.txt");
+  pickerFile.append("file_download.nonext.txt");
 
   const defaultFile = defaultDir.clone();
-  defaultFile.append("file_download.txt");
+  defaultFile.append("file_download.nonext.txt");
 
   const {MockFilePicker} = SpecialPowers;
   MockFilePicker.init(window);
@@ -61,6 +61,11 @@ add_task(async function test_downloads_saveAs() {
     // On picker 'show' event, choose the filename that was set as the default
     // and append it to the picker's download directory
     let file = pickerDir.clone();
+
+    // Assert that the downloads API configures both default properties.
+    is(fp.defaultString, "file_download.nonext.txt", "Got the expected FilePicker defaultString");
+    is(fp.defaultExtension, "txt", "Got the expected FilePicker defaultExtension");
+
     file.append(fp.defaultString);
     MockFilePicker.setFiles([file]);
   };
@@ -101,7 +106,7 @@ add_task(async function test_downloads_saveAs() {
 
     MockFilePicker.returnValue = MockFilePicker.returnOK;
 
-    extension.sendMessage("file_download.txt", saveAs);
+    extension.sendMessage("file_download.nonext.txt", saveAs);
     let result = await extension.awaitMessage("done");
     ok(result.ok, `downloads.download() works with saveAs=${saveAs}`);
 
@@ -112,7 +117,7 @@ add_task(async function test_downloads_saveAs() {
     // Test the user canceling the save dialog.
     MockFilePicker.returnValue = MockFilePicker.returnCancel;
 
-    extension.sendMessage("file_download.txt", saveAs);
+    extension.sendMessage("file_download.nonext.txt", saveAs);
     result = await extension.awaitMessage("done");
 
     ok(!result.ok, "download rejected if the user cancels the dialog");
@@ -123,7 +128,7 @@ add_task(async function test_downloads_saveAs() {
   async function testNoFilePicker(saveAs) {
     ok(!defaultFile.exists(), "the file should have been cleaned up properly previously");
 
-    extension.sendMessage("file_download.txt", saveAs);
+    extension.sendMessage("file_download.nonext.txt", saveAs);
     let result = await extension.awaitMessage("done");
     ok(result.ok, `downloads.download() works with saveAs=${saveAs}`);
 
-- 
2.11.4.GIT