[gtk/gtk-3-24: 2/9] gtktextview: Shuffle the places doing IM reset

[Carlos Garnacho <carlosg src gnome org>]

commit 0a8b0025e3102d2bd9977a011dfb884d36cfa1a5
Author: Carlos Garnacho <carlosg gnome org>
Date:   Thu Aug 18 00:58:14 2022 +0200

    gtktextview: Shuffle the places doing IM reset
    
    During text widget manipulation (inserting or deleting text via keyboard)
    the IM context is reset somewhat early, before the actual change took place.
    This makes IM lag behind in terms of surrounding text and cursor position.
    
    Shuffle these IM reset calls so that they happen after the changes, and
    ensure that the IM is actually reset, since that is currently toggled on
    a pretty narrow set of circumstances.
    
    Also, fix a bug during GtkEventControllerKey::im-update where the condition
    on cursor position editability to reset the IM context was inverted.

 gtk/gtktextview.c | 29 ++++++++++++++++++++---------
 1 file changed, 20 insertions(+), 9 deletions(-)
---
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index 9651c4a21f..148f744381 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -5513,7 +5513,7 @@ gtk_text_view_key_press_event (GtkWidget *widget, GdkEventKey *event)
   if (gtk_im_context_filter_keypress (priv->im_context, event))
     {
       priv->need_im_reset = TRUE;
-      if (!can_insert)
+      if (can_insert)
         gtk_text_view_reset_im_context (text_view);
       retval = TRUE;
     }
@@ -6564,8 +6564,6 @@ gtk_text_view_move_cursor (GtkTextView     *text_view,
       return;
     }
 
-  gtk_text_view_reset_im_context (text_view);
-
   if (step == GTK_MOVEMENT_PAGES)
     {
       if (!gtk_text_view_scroll_pages (text_view, count, extend_selection))
@@ -6749,6 +6747,9 @@ gtk_text_view_move_cursor (GtkTextView     *text_view,
 
   gtk_text_view_check_cursor_blink (text_view);
   gtk_text_view_pend_cursor_blink (text_view);
+
+  priv->need_im_reset = TRUE;
+  gtk_text_view_reset_im_context (text_view);
 }
 
 static void
@@ -7039,14 +7040,16 @@ gtk_text_view_delete_from_cursor (GtkTextView   *text_view,
 
   priv = text_view->priv;
 
-  gtk_text_view_reset_im_context (text_view);
-
   if (type == GTK_DELETE_CHARS)
     {
       /* Char delete deletes the selection, if one exists */
       if (gtk_text_buffer_delete_selection (get_buffer (text_view), TRUE,
                                             priv->editable))
-        return;
+        {
+          priv->need_im_reset = TRUE;
+          gtk_text_view_reset_im_context (text_view);
+          return;
+        }
     }
 
   gtk_text_buffer_get_iter_at_mark (get_buffer (text_view), &insert,
@@ -7173,6 +7176,9 @@ gtk_text_view_delete_from_cursor (GtkTextView   *text_view,
     {
       gtk_widget_error_bell (GTK_WIDGET (text_view));
     }
+
+  priv->need_im_reset = TRUE;
+  gtk_text_view_reset_im_context (text_view);
 }
 
 static void
@@ -7183,12 +7189,14 @@ gtk_text_view_backspace (GtkTextView *text_view)
 
   priv = text_view->priv;
 
-  gtk_text_view_reset_im_context (text_view);
-
   /* Backspace deletes the selection, if one exists */
   if (gtk_text_buffer_delete_selection (get_buffer (text_view), TRUE,
                                         priv->editable))
-    return;
+    {
+      priv->need_im_reset = TRUE;
+      gtk_text_view_reset_im_context (text_view);
+      return;
+    }
 
   gtk_text_buffer_get_iter_at_mark (get_buffer (text_view),
                                     &insert,
@@ -7201,6 +7209,9 @@ gtk_text_view_backspace (GtkTextView *text_view)
       DV(g_print (G_STRLOC": scrolling onscreen\n"));
       gtk_text_view_scroll_mark_onscreen (text_view,
                                           gtk_text_buffer_get_insert (get_buffer (text_view)));
+
+      priv->need_im_reset = TRUE;
+      gtk_text_view_reset_im_context (text_view);
     }
   else
     {