[gthumb/gthumb-3-10] Fixed long UI freeze after cutting/pasting many files

[Paolo Bacchilega <paobac src gnome org>]

commit eccf84c5d8fc0e9324c4607b65e698cac65ad2a4
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Fri Sep 18 18:47:45 2020 +0200

    Fixed long UI freeze after cutting/pasting many files
    
    Compress the events by emitting a single event if the parent is the
    same.

 gthumb/gth-file-source-vfs.c | 33 ++++++++++++++++++++++++++++-----
 1 file changed, 28 insertions(+), 5 deletions(-)
---
diff --git a/gthumb/gth-file-source-vfs.c b/gthumb/gth-file-source-vfs.c
index df318346..7a4d1f6a 100644
--- a/gthumb/gth-file-source-vfs.c
+++ b/gthumb/gth-file-source-vfs.c
@@ -455,12 +455,13 @@ process_event_queue (gpointer data)
 
        monitor = gth_main_get_default_monitor ();
        for (event_type = 0; event_type < GTH_MONITOR_N_EVENTS; event_type++) {
+               GFile *list_parent = NULL;
+               GList *list = NULL;
                GList *scan;
 
                for (scan = monitor_queue[event_type]; scan; scan = scan->next) {
                        GFile *file = scan->data;
                        GFile *parent;
-                       GList *list;
 
 #ifdef DEBUG_MONITOR
                        switch (event_type) {
@@ -477,16 +478,38 @@ process_event_queue (gpointer data)
                        g_print (" ==> %s\n", g_file_get_uri (file));
 #endif
 
+                       /* Compress the events: emits a single event if the
+                        * parent is the same. */
+
                        parent = g_file_get_parent (file);
-                       list = g_list_prepend (NULL, g_object_ref (file));
+                       if (_g_file_equal (parent, list_parent)) {
+                               list = g_list_prepend (list, g_object_ref (file));
+                       }
+                       else {
+                               if (list != NULL) {
+                                       gth_monitor_folder_changed (monitor,
+                                                                   list_parent,
+                                                                   list,
+                                                                   event_type);
+
+                                       _g_object_list_unref (list);
+                                       _g_object_unref (list_parent);
+                               }
+                               list = g_list_prepend (NULL, g_object_ref (file));
+                               list_parent = g_object_ref (parent);
+                       }
+                       g_object_unref (parent);
+               }
+
+               if (list != NULL) {
                        gth_monitor_folder_changed (monitor,
-                                                   parent,
+                                                   list_parent,
                                                    list,
                                                    event_type);
-
                        _g_object_list_unref (list);
-                       g_object_unref (parent);
+                       _g_object_unref (list_parent);
                }
+
                _g_object_list_unref (monitor_queue[event_type]);
                monitor_queue[event_type] = NULL;
        }