When the download folder does not exist, change the download folder to a user's "Downloads"

chrome/browser/download/save_package.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/download/save_package.h"
 
 #include <algorithm>
 
 #include "base/file_path.h"
 #include "base/file_util.h"
 #include "base/i18n/file_util_icu.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
+#include "base/path_service.h"
 #include "base/stl_util-inl.h"
 #include "base/string_piece.h"
 #include "base/string_split.h"
 #include "base/sys_string_conversions.h"
 #include "base/task.h"
 #include "base/threading/thread.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/download/download_item.h"
 #include "chrome/browser/download/download_item_model.h"
@@ skipping 1236 matching lines @@
   // before calling to it.
   PrefService* prefs = tab_contents()->profile()->GetPrefs();
   FilePath website_save_dir = GetSaveDirPreference(prefs);
   FilePath download_save_dir = prefs->GetFilePath(
       prefs::kDownloadDefaultDirectory);
   std::string mime_type = tab_contents()->contents_mime_type();
 
   BrowserThread::PostTask(
       BrowserThread::FILE, FROM_HERE,
       NewRunnableMethod(this, &SavePackage::CreateDirectoryOnFileThread,
-          website_save_dir, download_save_dir, mime_type));
+                        website_save_dir, download_save_dir, mime_type));
+}
+
+void SavePackage::GetSaveInfo(const FilePath& website_save_dir,

[Randy Smith (Not in Mondays), 2011/05/31 23:03:10]

It's a minor point, but it would seem relatively easy to share code between this
function and the variation without arguments.

[haraken1, 2011/06/02 09:13:22]

I removed this GetSaveInfo(). Instead, I added
DownloadTabHelper::ChangeSaveDirectoryPrefs() and
DownloadTabHelper::RestoreSaveDirectoryPrefs(). As I commented in
download_tab_helper.h, if we want to change the default folder preferences used
for some tests, then 

(1) call ChangeSaveDirectoryPrefs() to change the preferences
(2) call GetSaveInfo(), which will use the prefs that we set in (1)
(3) call RestoreSaveDirectoryPrefs() to restore the preferences

+                              const FilePath& download_save_dir,
+                              SavePackageType save_type) {
+  PrefService* prefs = tab_contents()->profile()->GetPrefs();
+  // Ignore the return value
+  GetSaveDirPreference(prefs);

[Randy Smith (Not in Mondays), 2011/05/31 23:03:10]

Could you document the side effect for which you're calling this function? 
Naively, it looks like a function that wouldn't have side effects.

[haraken1, 2011/06/02 09:13:22]

This is now unnecessary since I removed this code. 

+  prefs->SetInteger(prefs::kSaveFileType, save_type);

[Randy Smith (Not in Mondays), 2011/05/31 23:03:10]

This looks like a global state change that isn't documented/suggested in the
header file comment.  Could you at least document why we're doing that here?  (I
might want to ask you to separate the global state change out from this function
after I understand better its purpose.)

[haraken1, 2011/06/02 09:13:22]

This is now unnecessary since I removed this code. 

+  std::string mime_type = tab_contents()->contents_mime_type();
+
+  BrowserThread::PostTask(
+      BrowserThread::FILE, FROM_HERE,
+      NewRunnableMethod(this, &SavePackage::CreateDirectoryOnFileThread,
+                        website_save_dir, download_save_dir, mime_type));
 }
 
 void SavePackage::CreateDirectoryOnFileThread(
     const FilePath& website_save_dir,
     const FilePath& download_save_dir,
     const std::string& mime_type) {
   FilePath save_dir;
-  // If the default html/websites save folder doesn't exist...
-  if (!file_util::DirectoryExists(website_save_dir)) {
-    // If the default download dir doesn't exist, create it.
-    if (!file_util::DirectoryExists(download_save_dir))
-      file_util::CreateDirectory(download_save_dir);
+  if (file_util::DirectoryExists(website_save_dir)) {
+    // If the default html/websites save folder exists,
+    // then use the default html/websites save folder.
+    save_dir = website_save_dir;
+  } else if (file_util::DirectoryExists(download_save_dir)) {
+    // If the default html/websites save folder does not exist
+    // but the default download folder exists,
+    // then use the default download folder.
     save_dir = download_save_dir;
   } else {
-    // If it does exist, use the default save dir param.
-    save_dir = website_save_dir;
+    // If both the above folders do not exist,
+    // use the user's "Downloads" folder.
+    if (!PathService::Get(chrome::DIR_DEFAULT_DOWNLOADS, &save_dir)) {
+      // Create the |download_save_dir| folder if we cannot get
+      // DIR_DEFAULT_DOWNLOADS (This will be a rare case).
+      save_dir = download_save_dir;
+    }
+    // Make sure that the folder does exist.
+    if (!file_util::CreateDirectory(save_dir))
+      LOG(ERROR) << "Failed to create " << save_dir.value();
   }
 
   bool can_save_as_complete = CanSaveAsComplete(mime_type);
   FilePath suggested_filename = GetSuggestedNameForSaveAs(can_save_as_complete,
                                                           mime_type);
   FilePath::StringType pure_file_name =
       suggested_filename.RemoveExtension().BaseName().value();
   FilePath::StringType file_name_ext = suggested_filename.Extension();
 
   // Need to make sure the suggested file name is not too long.
@@ skipping 169 matching lines @@
 }
 
 // SelectFileDialog::Listener interface.
 void SavePackage::FileSelected(const FilePath& path,
                                int index, void* params) {
   ContinueSave(path, index);
 }
 
 void SavePackage::FileSelectionCanceled(void* params) {
 }