[gtksourceview/wip/smart-backspace] view: bug fix and improvements of do_smart_backspace()

[Sébastien Wilmet <swilmet src gnome org>]

commit 9910649c28a5a2fb011bd186c5c13aaae19546a9
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Aug 16 16:31:12 2015 +0200

    view: bug fix and improvements of do_smart_backspace()
    
    Use insert_interactive() and delete_interactive().

 gtksourceview/gtksourceview.c |   72 +++++++++++++++++++---------------------
 1 files changed, 34 insertions(+), 38 deletions(-)
---
diff --git a/gtksourceview/gtksourceview.c b/gtksourceview/gtksourceview.c
index 1db25f3..536f00a 100644
--- a/gtksourceview/gtksourceview.c
+++ b/gtksourceview/gtksourceview.c
@@ -4069,14 +4069,15 @@ gtk_source_view_do_smart_backspace (GtkSourceView *view,
                                     guint          modifiers)
 {
        GtkTextBuffer *buffer;
+       gboolean default_editable;
        GtkTextIter insert;
        GtkTextIter end;
-       GtkTextIter tmp;
+       GtkTextIter iter;
        guint visual_column;
        gint indent_width;
-       gint tab_width;
 
        buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (view));
+       default_editable = gtk_text_view_get_editable (GTK_TEXT_VIEW (view));
 
        if (gtk_text_buffer_get_selection_bounds (buffer, &insert, &end))
        {
@@ -4090,59 +4091,50 @@ gtk_source_view_do_smart_backspace (GtkSourceView *view,
                 * end of the previous line. Anything more than that is non-obvious because it requires
                 * looking in a position other than where the cursor is.
                 */
-               if ((gtk_text_iter_get_line_offset (&insert) == 0) && (gtk_text_iter_get_line (&insert) > 0))
+               if ((gtk_text_iter_get_line_offset (&insert) == 0) &&
+                   (gtk_text_iter_get_line (&insert) > 0))
                {
-                       gtk_text_buffer_begin_user_action (buffer);
-                       gtk_text_iter_backward_char (&insert);
-                       gtk_text_buffer_delete (buffer, &insert, &end);
-                       gtk_text_buffer_end_user_action (buffer);
-
+                       gtk_text_iter_backward_cursor_position (&insert);
+                       gtk_text_buffer_delete_interactive (buffer, &insert, &end, default_editable);
                        return TRUE;
                }
        }
 
-       /* if the line isn't empty up to our cursor, ignore */
-       tmp = insert;
-       while (TRUE)
+       /* If the line isn't empty up to our cursor, ignore. */
+       iter = insert;
+       gtk_text_iter_set_line_offset (&iter, 0);
+       while (gtk_text_iter_compare (&iter, &insert) < 0)
        {
-               gunichar ch;
-
-               ch = gtk_text_iter_get_char (&tmp);
+               gunichar ch = gtk_text_iter_get_char (&iter);
 
-               if ((ch != 0) && !g_unichar_isspace (ch))
+               if (!g_unichar_isspace (ch))
                {
                        return FALSE;
                }
 
-               if (gtk_text_iter_starts_line (&tmp))
-               {
-                       break;
-               }
-
-               gtk_text_iter_backward_char (&tmp);
+               gtk_text_iter_forward_char (&iter);
        }
 
-       /*
-        * If <Control>BackSpace was specified, delete up to the zero position.
-        */
+       /* If <Control>BackSpace was specified, delete up to the zero position. */
        if ((modifiers & GDK_CONTROL_MASK) != 0)
        {
-               gtk_text_buffer_begin_user_action (buffer);
                gtk_text_iter_set_line_offset (&insert, 0);
-               gtk_text_buffer_delete (buffer, &insert, &end);
-               gtk_text_buffer_end_user_action (buffer);
-
+               gtk_text_buffer_delete_interactive (buffer, &insert, &end, default_editable);
                return TRUE;
        }
 
        visual_column = gtk_source_view_get_visual_column (view, &insert);
-       indent_width = gtk_source_view_get_indent_width (view);
-       tab_width = gtk_source_view_get_tab_width (view);
+       indent_width = view->priv->indent_width;
        if (indent_width <= 0)
        {
-               indent_width = tab_width;
+               indent_width = view->priv->tab_width;
        }
 
+       g_return_val_if_fail (indent_width > 0, FALSE);
+
+       /* If the cursor is not at an indent_width boundary, it probably means
+        * that we want to adjust the spaces.
+        */
        if ((gint)visual_column < indent_width)
        {
                return FALSE;
@@ -4150,14 +4142,15 @@ gtk_source_view_do_smart_backspace (GtkSourceView *view,
 
        if ((visual_column % indent_width) == 0)
        {
-               gint target_column = visual_column - indent_width;
+               guint target_column;
                gunichar ch;
 
-               g_assert (target_column >= 0);
+               g_assert ((gint)visual_column >= indent_width);
+               target_column = visual_column - indent_width;
 
-               while ((gint)gtk_source_view_get_visual_column (view, &insert) > target_column)
+               while (gtk_source_view_get_visual_column (view, &insert) > target_column)
                {
-                       gtk_text_iter_backward_char (&insert);
+                       gtk_text_iter_backward_cursor_position (&insert);
                        ch = gtk_text_iter_get_char (&insert);
 
                        if (!g_unichar_isspace (ch))
@@ -4173,10 +4166,13 @@ gtk_source_view_do_smart_backspace (GtkSourceView *view,
                }
 
                gtk_text_buffer_begin_user_action (buffer);
-               gtk_text_buffer_delete (buffer, &insert, &end);
-               while ((gint)gtk_source_view_get_visual_column (view, &insert) < target_column)
+               gtk_text_buffer_delete_interactive (buffer, &insert, &end, default_editable);
+               while (gtk_source_view_get_visual_column (view, &insert) < target_column)
                {
-                       gtk_text_buffer_insert (buffer, &insert, " ", 1);
+                       if (!gtk_text_buffer_insert_interactive (buffer, &insert, " ", 1, default_editable))
+                       {
+                               break;
+                       }
                }
                gtk_text_buffer_end_user_action (buffer);