[gedit/wip/loader-saver] tab: better handling of the create_backup flag

[Sébastien Wilmet <swilmet src gnome org>]

commit 8b22e69c930e2e466ac52767c7a827dca50e12fa
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Mon Jun 30 18:11:45 2014 +0200

    tab: better handling of the create_backup flag

 gedit/gedit-tab.c |  112 ++++++++++++++++++++++++++++++++++++++++-------------
 1 files changed, 85 insertions(+), 27 deletions(-)
---
diff --git a/gedit/gedit-tab.c b/gedit/gedit-tab.c
index 148ddbe..b18a6bf 100644
--- a/gedit/gedit-tab.c
+++ b/gedit/gedit-tab.c
@@ -74,6 +74,26 @@ struct _GeditTabPrivate
 
        gint                    ask_if_externally_modified : 1;
 
+       /* Notes about the create_backup saver flag:
+        * - At the beginning of a new file saving, force_no_backup is reset to
+        *   FALSE. The create_backup flag is set to the saver if it is enabled
+        *   in GSettings and if it isn't an auto-save.
+        * - If creating the backup gives an error, and if the user wants to
+        *   save the file without the backup, force_no_backup is set to TRUE
+        *   and the create_backup flag is removed from the saver.
+        *   force_no_backup as TRUE means that the create_backup flag should
+        *   never be added again to the saver (for the current file saving).
+        * - When another error occurs and if the user explicitly retry again
+        *   the file saving, the create_backup flag is added to the saver if
+        *   (1) it is enabled in GSettings, (2) if force_no_backup is FALSE.
+        * - The create_backup flag is added when the user expressed his or her
+        *   willing to save the file, by pressing a button for example. For an
+        *   auto-save, the create_backup flag is thus not added initially, but
+        *   can be added later when an error occurs and the user clicks on a
+        *   button in the info bar to retry the file saving.
+        */
+       guint                   force_no_backup : 1;
+
        /* tmp data for loading */
        guint                   user_requested_encoding : 1;
 };
@@ -229,6 +249,7 @@ static void
 clear_saving (GeditTab *tab)
 {
        g_clear_object (&tab->priv->saver);
+       tab->priv->force_no_backup = FALSE;
 }
 
 static void
@@ -939,6 +960,33 @@ unrecoverable_saving_error_info_bar_response (GtkWidget *info_bar,
        gtk_widget_grab_focus (GTK_WIDGET (view));
 }
 
+/* Sets the save flags after an info bar response. */
+static void
+response_set_save_flags (GeditTab                *tab,
+                        GtkSourceFileSaverFlags  save_flags)
+{
+       gboolean create_backup;
+
+       create_backup = g_settings_get_boolean (tab->priv->editor,
+                                               GEDIT_SETTINGS_CREATE_BACKUP_COPY);
+
+       /* If we are here, it means that the user expressed his or her willing
+        * to save the file, by pressing a button in the info bar. So even if
+        * the file saving was initially an auto-save, we set the create_backup
+        * flag (if the conditions are met).
+        */
+       if (create_backup && !tab->priv->force_no_backup)
+       {
+               save_flags |= GTK_SOURCE_FILE_SAVER_FLAGS_CREATE_BACKUP;
+       }
+       else
+       {
+               save_flags &= ~GTK_SOURCE_FILE_SAVER_FLAGS_CREATE_BACKUP;
+       }
+
+       gtk_source_file_saver_set_flags (tab->priv->saver, save_flags);
+}
+
 static void
 invalid_character_info_bar_response (GtkWidget *info_bar,
                                      gint       response_id,
@@ -957,7 +1005,7 @@ invalid_character_info_bar_response (GtkWidget *info_bar,
 
                save_flags = gtk_source_file_saver_get_flags (tab->priv->saver);
                save_flags |= GTK_SOURCE_FILE_SAVER_FLAGS_IGNORE_INVALID_CHARS;
-               gtk_source_file_saver_set_flags (tab->priv->saver, save_flags);
+               response_set_save_flags (tab, save_flags);
 
                /* Force saving */
                save (tab);
@@ -981,9 +1029,9 @@ no_backup_error_info_bar_response (GtkWidget *info_bar,
 
                g_return_if_fail (tab->priv->saver != NULL);
 
+               tab->priv->force_no_backup = TRUE;
                save_flags = gtk_source_file_saver_get_flags (tab->priv->saver);
-               save_flags &= ~GTK_SOURCE_FILE_SAVER_FLAGS_CREATE_BACKUP;
-               gtk_source_file_saver_set_flags (tab->priv->saver, save_flags);
+               response_set_save_flags (tab, save_flags);
 
                /* Force saving */
                save (tab);
@@ -1013,7 +1061,7 @@ externally_modified_error_info_bar_response (GtkWidget *info_bar,
 
                save_flags = gtk_source_file_saver_get_flags (tab->priv->saver);
                save_flags |= GTK_SOURCE_FILE_SAVER_FLAGS_IGNORE_MODIFICATION_TIME;
-               gtk_source_file_saver_set_flags (tab->priv->saver, save_flags);
+               response_set_save_flags (tab, save_flags);
 
                /* Force saving */
                save (tab);
@@ -2246,24 +2294,25 @@ save (GeditTab *tab)
                                          tab);
 }
 
+/* Gets the initial save flags, when launching a new FileSaver. */
 static GtkSourceFileSaverFlags
-get_save_flags (GeditTab *tab,
-               gboolean  auto_save)
+get_initial_save_flags (GeditTab *tab,
+                       gboolean  auto_save)
 {
        GtkSourceFileSaverFlags save_flags;
        gboolean create_backup;
 
        save_flags = tab->priv->save_flags;
 
+       /* force_no_backup must have been reset to FALSE for a new file saving. */
+       g_return_val_if_fail (!tab->priv->force_no_backup, save_flags);
+
        create_backup = g_settings_get_boolean (tab->priv->editor,
                                                GEDIT_SETTINGS_CREATE_BACKUP_COPY);
 
        /* In case of autosaving, we need to preserve the backup that was produced
         * the last time the user "manually" saved the file. So we don't set the
         * CREATE_BACKUP flag for an automatic file saving.
-        * TODO (swilmet) In the case a recoverable error happens while saving,
-        * set the CREATE_BACKUP flag since the user expressed his willing of
-        * saving the file.
         */
        if (create_backup && !auto_save)
        {
@@ -2286,10 +2335,19 @@ _gedit_tab_save (GeditTab *tab)
                          tab->priv->state == GEDIT_TAB_STATE_EXTERNALLY_MODIFIED_NOTIFICATION ||
                          tab->priv->state == GEDIT_TAB_STATE_SHOWING_PRINT_PREVIEW);
 
+       if (tab->priv->saver != NULL)
+       {
+               g_warning ("GeditTab: file saver already exists.");
+               g_object_unref (tab->priv->saver);
+               tab->priv->saver = NULL;
+       }
+
+       clear_saving (tab);
+
        doc = gedit_tab_get_document (tab);
        g_return_if_fail (!gedit_document_is_untitled (doc));
 
-       save_flags = get_save_flags (tab, FALSE);
+       save_flags = get_initial_save_flags (tab, FALSE);
 
        if (tab->priv->state == GEDIT_TAB_STATE_EXTERNALLY_MODIFIED_NOTIFICATION)
        {
@@ -2303,12 +2361,6 @@ _gedit_tab_save (GeditTab *tab)
        file = gedit_document_get_file (doc);
        location = gtk_source_file_get_location (file);
 
-       if (tab->priv->saver != NULL)
-       {
-               g_warning ("GeditTab: file saver already exists.");
-               g_object_unref (tab->priv->saver);
-       }
-
        tab->priv->saver = gtk_source_file_saver_new (file, location);
        gtk_source_file_saver_set_flags (tab->priv->saver, save_flags);
 
@@ -2352,18 +2404,21 @@ gedit_tab_auto_save (GeditTab *tab)
        /* Set auto_save_timeout to 0 since the timeout is going to be destroyed */
        tab->priv->auto_save_timeout = 0;
 
-       file = gedit_document_get_file (doc);
-       location = gtk_source_file_get_location (file);
-
        if (tab->priv->saver != NULL)
        {
                g_warning ("GeditTab: file saver already exists.");
                g_object_unref (tab->priv->saver);
+               tab->priv->saver = NULL;
        }
 
+       clear_saving (tab);
+
+       file = gedit_document_get_file (doc);
+       location = gtk_source_file_get_location (file);
+
        tab->priv->saver = gtk_source_file_saver_new (file, location);
 
-       save_flags = get_save_flags (tab, TRUE);
+       save_flags = get_initial_save_flags (tab, TRUE);
        gtk_source_file_saver_set_flags (tab->priv->saver, save_flags);
 
        save (tab);
@@ -2390,12 +2445,21 @@ _gedit_tab_save_as (GeditTab                 *tab,
        g_return_if_fail (G_IS_FILE (location));
        g_return_if_fail (encoding != NULL);
 
+       if (tab->priv->saver != NULL)
+       {
+               g_warning ("GeditTab: file saver already exists.");
+               g_object_unref (tab->priv->saver);
+               tab->priv->saver = NULL;
+       }
+
+       clear_saving (tab);
+
        doc = gedit_tab_get_document (tab);
 
        /* reset the save flags, when saving as */
        tab->priv->save_flags = GTK_SOURCE_FILE_SAVER_FLAGS_NONE;
 
-       save_flags = get_save_flags (tab, FALSE);
+       save_flags = get_initial_save_flags (tab, FALSE);
 
        if (tab->priv->state == GEDIT_TAB_STATE_EXTERNALLY_MODIFIED_NOTIFICATION)
        {
@@ -2418,12 +2482,6 @@ _gedit_tab_save_as (GeditTab                 *tab,
                save_flags |= GTK_SOURCE_FILE_SAVER_FLAGS_IGNORE_MODIFICATION_TIME;
        }
 
-       if (tab->priv->saver != NULL)
-       {
-               g_warning ("GeditTab: file saver already exists.");
-               g_object_unref (tab->priv->saver);
-       }
-
        tab->priv->saver = gtk_source_file_saver_new (file, location);
 
        gtk_source_file_saver_set_encoding (tab->priv->saver, encoding);