[pygobject] Do not override Treeview.enable_model_drag_xx for GTK4

[Christoph Reiter <creiter src gnome org>]

commit 8ea38cd186f5e33d8e328a8b66180f7ca83abedc
Author: Arjan Molenaar <gaphor gmail com>
Date:   Wed May 19 15:36:42 2021 +0200

    Do not override Treeview.enable_model_drag_xx for GTK4
    
    Those methods require a Gdk.ContentFormats object.

 gi/overrides/Gtk.py         | 22 ++++++++++++----------
 tests/test_overrides_gtk.py | 15 ++++++++++++++-
 2 files changed, 26 insertions(+), 11 deletions(-)
---
diff --git a/gi/overrides/Gtk.py b/gi/overrides/Gtk.py
index f53ec6bd..d9ec6fbe 100644
--- a/gi/overrides/Gtk.py
+++ b/gi/overrides/Gtk.py
@@ -1359,16 +1359,18 @@ class TreeView(Gtk.TreeView, Container):
     get_visible_range = strip_boolean_result(Gtk.TreeView.get_visible_range)
     get_dest_row_at_pos = strip_boolean_result(Gtk.TreeView.get_dest_row_at_pos)
 
-    def enable_model_drag_source(self, start_button_mask, targets, actions):
-        target_entries = _construct_target_list(targets)
-        super(TreeView, self).enable_model_drag_source(start_button_mask,
-                                                       target_entries,
-                                                       actions)
-
-    def enable_model_drag_dest(self, targets, actions):
-        target_entries = _construct_target_list(targets)
-        super(TreeView, self).enable_model_drag_dest(target_entries,
-                                                     actions)
+    if GTK2 or GTK3:
+        def enable_model_drag_source(self, start_button_mask, targets, actions):
+            target_entries = _construct_target_list(targets)
+            super(TreeView, self).enable_model_drag_source(start_button_mask,
+                                                           target_entries,
+                                                           actions)
+
+    if GTK2 or GTK3:
+        def enable_model_drag_dest(self, targets, actions):
+            target_entries = _construct_target_list(targets)
+            super(TreeView, self).enable_model_drag_dest(target_entries,
+                                                         actions)
 
     def scroll_to_cell(self, path, column=None, use_align=False, row_align=0.0, col_align=0.0):
         if not isinstance(path, Gtk.TreePath):
diff --git a/tests/test_overrides_gtk.py b/tests/test_overrides_gtk.py
index 6bd2345a..50c1ad8b 100644
--- a/tests/test_overrides_gtk.py
+++ b/tests/test_overrides_gtk.py
@@ -786,7 +786,7 @@ class TestGtk(unittest.TestCase):
 
     @unittest.skipIf(sys.platform == "darwin", "crashes")
     @unittest.skipIf(GTK4, "uses lots of gtk3 only api")
-    def test_drag_target_list_gtk3(self):
+    def test_tree_view_drag_target_list_gtk3(self):
         mixed_target_list = [Gtk.TargetEntry.new('test0', 0, 0),
                              ('test1', 1, 1),
                              Gtk.TargetEntry.new('test2', 2, 2),
@@ -818,6 +818,19 @@ class TestGtk(unittest.TestCase):
         treeview.enable_model_drag_dest(mixed_target_list,
                                         Gdk.DragAction.DEFAULT | Gdk.DragAction.MOVE)
 
+    @unittest.skipUnless(GTK4, "gtk4 only")
+    def test_tree_view_drag_content_formats_gtk4(self):
+        content_formats = Gdk.ContentFormats.new(
+            ["application/json", "GTK_TREE_MODEL_ROW"]
+        )
+        treeview = Gtk.TreeView()
+        treeview.enable_model_drag_source(Gdk.ModifierType.BUTTON1_MASK,
+                                          content_formats,
+                                          Gdk.DragAction.MOVE)
+
+        treeview.enable_model_drag_dest(content_formats,
+                                        Gdk.DragAction.MOVE)
+
     @unittest.skipIf(Gtk_version == "4.0", "not in gtk4")
     def test_scrollbar(self):
         adjustment = Gtk.Adjustment()