[gnome-builder/wip/libide] libide: keep the insert mark on screen during various changes

[Christian Hergert <chergert src gnome org>]

commit 67882fbfc82cc60693690bd969c10bc7f09f32bb
Author: Christian Hergert <christian hergert me>
Date:   Mon Mar 9 17:23:40 2015 -0700

    libide: keep the insert mark on screen during various changes
    
    This uses the just-added helpers to move the mark taking into account
    the scroll offset.
    
    This does it's part to ensure that while inserting (even via gsignalactions
    that we keep the cursor on screen).

 libide/ide-source-view.c |   27 +++++++++++++++++++++++++++
 1 files changed, 27 insertions(+), 0 deletions(-)
---
diff --git a/libide/ide-source-view.c b/libide/ide-source-view.c
index 22b314f..277dd00 100644
--- a/libide/ide-source-view.c
+++ b/libide/ide-source-view.c
@@ -102,6 +102,8 @@ typedef struct
   gulong                       buffer_notify_highlight_diagnostics_handler;
   gulong                       buffer_notify_language_handler;
 
+  guint                        change_sequence;
+
   gint                         target_line_offset;
   guint                        count;
 
@@ -742,9 +744,12 @@ static void
 ide_source_view__buffer_changed_cb (IdeSourceView *self,
                                     IdeBuffer     *buffer)
 {
+  IdeSourceViewPrivate *priv = ide_source_view_get_instance_private (self);
+
   g_assert (IDE_IS_SOURCE_VIEW (self));
   g_assert (IDE_IS_BUFFER (buffer));
 
+  priv->change_sequence++;
 }
 
 static void
@@ -1469,6 +1474,11 @@ ide_source_view_do_indent (IdeSourceView *self,
       gtk_text_buffer_end_user_action (buffer);
 
       /*
+       * Make sure we stay in the visible rect.
+       */
+      ide_source_view_scroll_mark_onscreen (self, insert);
+
+      /*
        * Keep our selves pinned to the bottom of the document if that makes sense.
        */
       if (at_bottom)
@@ -1552,12 +1562,21 @@ ide_source_view_key_press_event (GtkWidget   *widget,
   IdeSourceView *self = (IdeSourceView *)widget;
   IdeSourceViewPrivate *priv = ide_source_view_get_instance_private (self);
   GtkTextBuffer *buffer;
+  GtkTextMark *insert;
   IdeSourceSnippet *snippet;
   gboolean ret = FALSE;
+  guint change_sequence;
 
   g_assert (IDE_IS_SOURCE_VIEW (self));
 
   buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (self));
+  insert = gtk_text_buffer_get_insert (buffer);
+
+  /*
+   * Check our current change sequence. If the buffer has changed during the
+   * key-press handler, we'll refocus our selves at the insert caret.
+   */
+  change_sequence = priv->change_sequence;
 
   /*
    * If we are in a non-default mode, dispatch the event to the mode. This allows custom
@@ -1642,6 +1661,9 @@ ide_source_view_key_press_event (GtkWidget   *widget,
   if (ret)
     ide_source_view_maybe_insert_match (self, event);
 
+  if (priv->change_sequence != change_sequence)
+    ide_source_view_scroll_mark_onscreen (self, insert);
+
   return ret;
 }
 
@@ -2014,6 +2036,7 @@ ide_source_view_real_insert_at_cursor_and_indent (IdeSourceView *self,
   gtk_text_buffer_end_user_action (buffer);
 
 maybe_scroll:
+  ide_source_view_scroll_mark_onscreen (self, gtk_text_buffer_get_insert (buffer));
   if (at_bottom)
     ide_source_view_scroll_to_bottom (self);
 
@@ -2609,6 +2632,7 @@ ide_source_view_real_insert_at_cursor (GtkTextView *text_view,
                                        const gchar *str)
 {
   IdeSourceView *self = (IdeSourceView *)text_view;
+  GtkTextBuffer *buffer;
   gboolean at_bottom;
 
   g_assert (IDE_IS_SOURCE_VIEW (self));
@@ -2619,6 +2643,9 @@ ide_source_view_real_insert_at_cursor (GtkTextView *text_view,
 
   GTK_TEXT_VIEW_CLASS (ide_source_view_parent_class)->insert_at_cursor (text_view, str);
 
+  buffer = gtk_text_view_get_buffer (text_view);
+  ide_source_view_scroll_mark_onscreen (self, gtk_text_buffer_get_insert (buffer));
+
   if (at_bottom)
     ide_source_view_scroll_to_bottom (self);
 }