[gjs: 1/2] tests: Add test for child_set_property() with null values

[Philip Chimento <pchimento src gnome org>]

commit e16a28807f6d92daeced1efce77fb5de73f821b4
Author: Florian Müllner <fmuellner gnome org>
Date:   Tue Aug 13 00:50:38 2019 +0200

    tests: Add test for child_set_property() with null values
    
    We have a custom override for this, as it's a difficult problem:
    null is too generic for meaningful type information (unset string,
    object, boxed, ...?), but the method will bail out if we pass a
    GValue of the wrong type.
    
    It is certainly worth a test case.
    
    https://gitlab.gnome.org/GNOME/gjs/issues/99

 installed-tests/js/testGtk.js | 11 +++++++++++
 1 file changed, 11 insertions(+)
---
diff --git a/installed-tests/js/testGtk.js b/installed-tests/js/testGtk.js
index 6cae626b..97038e38 100755
--- a/installed-tests/js/testGtk.js
+++ b/installed-tests/js/testGtk.js
@@ -204,4 +204,15 @@ describe('Gtk overrides', function () {
          */
         expect(() => Gtk.Clipboard.get(null)).toThrowError(/null/);
     });
+
+    it('uses the correct GType for null child properties', function () {
+        let s = new Gtk.Stack();
+        let p = new Gtk.Box();
+
+        s.add_named(p, 'foo');
+        expect(s.get_child_by_name('foo')).toBe(p);
+
+        s.child_set_property(p, 'name', null);
+        expect(s.get_child_by_name('foo')).toBeNull();
+    });
 });