file-conflict-dialog: Fix crash on extensionless filenames

The new filename entry has the automatically suggested part of the name
selected for convenience since 9108b4028b7f476b598bc664079fd6d115801b66

However, the logic for this relies on extensions offsets, causing
crashes when failing to handle the extensionless case, which is common
for folders.

So, improve the logic here to handle extensionless filenames, looking
at their length instead.

Fixes https://gitlab.gnome.org/GNOME/nautilus/-/issues/1841

1 files changed, 19 insertions, 6 deletions

diff --git a/src/nautilus-file-conflict-dialog.c b/src/nautilus-file-conflict-dialog.c
index 28fa972a3..678f96323 100644
--- a/src/nautilus-file-conflict-dialog.c
+++ b/src/nautilus-file-conflict-dialog.c
@@ -191,6 +191,23 @@ entry_text_changed_cb (GtkEditable                *entry,
     }
 }
 
+static int
+get_character_position_after_basename (const gchar *filename)
+{
+    const gchar *extension;
+
+    extension = eel_filename_get_extension_offset (filename);
+
+    if (extension == NULL)
+    {
+        /* If the filename has got no extension, we want the position of the
+         * the terminating null. */
+        return (int) g_utf8_strlen (filename, -1);
+    }
+
+    return g_utf8_pointer_to_offset (filename, extension);
+}
+
 static void
 on_expanded_notify (GtkExpander                *w,
                     GParamSpec                 *pspec,
@@ -212,15 +229,11 @@ on_expanded_notify (GtkExpander                *w,
              * replace the "(1)" bits with with something more meaningful, so
              * select this region for convenience. */
 
-            const gchar *offset;
             int start_pos;
             int end_pos;
 
-            offset = eel_filename_get_extension_offset (dialog->conflict_name);
-            start_pos = g_utf8_pointer_to_offset (dialog->conflict_name, offset);
-
-            offset = eel_filename_get_extension_offset (dialog->suggested_name);
-            end_pos = g_utf8_pointer_to_offset (dialog->suggested_name, offset);
+            start_pos = get_character_position_after_basename (dialog->conflict_name);
+            end_pos = get_character_position_after_basename (dialog->suggested_name);
 
             gtk_editable_select_region (GTK_EDITABLE (dialog->entry), start_pos, end_pos);
         }