[gedit/wip/search-timeout] Incremental search: 1 second timeout for <= 2 chars

[Sébastien Wilmet <swilmet src gnome org>]

commit 8a6310632267023c09b05cd253e8a896df5ff9a1
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Mon Sep 15 21:46:52 2014 +0200

    Incremental search: 1 second timeout for <= 2 chars
    
    Searching only one or two characters is most of the time useless. On Mac
    OS X there are some performance problems with lots of search
    occurrences.

 gedit/gedit-view-frame.c |   96 +++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 90 insertions(+), 6 deletions(-)
---
diff --git a/gedit/gedit-view-frame.c b/gedit/gedit-view-frame.c
index a5810f7..92c6e9b 100644
--- a/gedit/gedit-view-frame.c
+++ b/gedit/gedit-view-frame.c
@@ -39,6 +39,11 @@
 
 #define FLUSH_TIMEOUT_DURATION 30 /* in seconds */
 
+/* Number of seconds before updating the search when the search entry contains
+ * <= 2 characters.
+ */
+#define UPDATE_SEARCH_TIMEOUT_DURATION 1
+
 #define SEARCH_POPUP_MARGIN 12
 
 typedef enum
@@ -74,6 +79,7 @@ struct _GeditViewFramePrivate
 
        guint flush_timeout_id;
        guint idle_update_entry_tag_id;
+       guint update_search_timeout_id;
        guint remove_entry_tag_timeout_id;
        gulong view_scroll_event_id;
        gulong search_entry_focus_out_id;
@@ -135,6 +141,12 @@ gedit_view_frame_dispose (GObject *object)
                frame->priv->idle_update_entry_tag_id = 0;
        }
 
+       if (frame->priv->update_search_timeout_id != 0)
+       {
+               g_source_remove (frame->priv->update_search_timeout_id);
+               frame->priv->update_search_timeout_id = 0;
+       }
+
        if (frame->priv->remove_entry_tag_timeout_id != 0)
        {
                g_source_remove (frame->priv->remove_entry_tag_timeout_id);
@@ -221,6 +233,12 @@ hide_search_widget (GeditViewFrame *frame,
                frame->priv->flush_timeout_id = 0;
        }
 
+       if (frame->priv->update_search_timeout_id != 0)
+       {
+               g_source_remove (frame->priv->update_search_timeout_id);
+               frame->priv->update_search_timeout_id = 0;
+       }
+
        gtk_revealer_set_reveal_child (frame->priv->revealer, FALSE);
 
        buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (frame->priv->view));
@@ -380,7 +398,8 @@ start_search (GeditViewFrame *frame)
 
        search_context = get_search_context (frame);
 
-       if (search_context == NULL)
+       if (search_context == NULL ||
+           frame->priv->start_mark == NULL)
        {
                return;
        }
@@ -765,9 +784,6 @@ update_search_text (GeditViewFrame *frame)
 {
        const gchar *entry_text = gtk_entry_get_text (GTK_ENTRY (frame->priv->search_entry));
 
-       g_free (frame->priv->search_text);
-       frame->priv->search_text = g_strdup (entry_text);
-
        if (gtk_source_search_settings_get_regex_enabled (frame->priv->search_settings))
        {
                gtk_source_search_settings_set_search_text (frame->priv->search_settings,
@@ -1150,6 +1166,75 @@ update_goto_line (GeditViewFrame *frame)
        }
 }
 
+static gboolean
+update_search_timeout_cb (GeditViewFrame *frame)
+{
+       frame->priv->update_search_timeout_id = 0;
+
+       update_search_text (frame);
+       start_search (frame);
+
+       return G_SOURCE_REMOVE;
+}
+
+static void
+disable_search (GeditViewFrame *frame)
+{
+       gtk_source_search_settings_set_search_text (frame->priv->search_settings, NULL);
+
+       set_search_state (frame, SEARCH_STATE_NORMAL);
+
+       if (frame->priv->start_mark != NULL)
+       {
+               GtkTextBuffer *buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (frame->priv->view));
+               GtkTextIter start_at;
+
+               gtk_text_buffer_get_iter_at_mark (buffer,
+                                                 &start_at,
+                                                 frame->priv->start_mark);
+
+               gtk_text_buffer_select_range (buffer, &start_at, &start_at);
+       }
+}
+
+static void
+update_search (GeditViewFrame *frame)
+{
+       const gchar *entry_text;
+       guint16 chars_count;
+
+       entry_text = gtk_entry_get_text (GTK_ENTRY (frame->priv->search_entry));
+
+       g_free (frame->priv->search_text);
+       frame->priv->search_text = g_strdup (entry_text);
+
+       if (frame->priv->update_search_timeout_id != 0)
+       {
+               g_source_remove (frame->priv->update_search_timeout_id);
+               frame->priv->update_search_timeout_id = 0;
+       }
+
+       chars_count = gtk_entry_get_text_length (GTK_ENTRY (frame->priv->search_entry));
+
+       if (chars_count <= 2)
+       {
+               /* Disable the search during the timeout. Otherwise old
+                * occurrences can still be highlighted when we delete text from
+                * the search entry (3 chars -> 2 chars).
+                */
+               disable_search (frame);
+
+               frame->priv->update_search_timeout_id =
+                       g_timeout_add_seconds (UPDATE_SEARCH_TIMEOUT_DURATION,
+                                              (GSourceFunc)update_search_timeout_cb,
+                                              frame);
+       }
+       else
+       {
+               update_search_timeout_cb (frame);
+       }
+}
+
 static void
 search_entry_changed_cb (GtkEntry       *entry,
                         GeditViewFrame *frame)
@@ -1158,8 +1243,7 @@ search_entry_changed_cb (GtkEntry       *entry,
 
        if (frame->priv->search_mode == SEARCH)
        {
-               update_search_text (frame);
-               start_search (frame);
+               update_search (frame);
        }
        else
        {