Update src/twisted/internet/test/test_glibbase.py

Co-authored-by: Adi Roiban <adiroiban@gmail.com>

src/twisted/internet/test/test_glibbase.py

@@ -67,17 +67,34 @@ def test_ensureFailsWhenImported(self):
         self.assertEqual(e.args, ("A message.",))
 
 
+
+try:
+    from twisted.internet import gireactor as _gireactor
+except ImportError:
+    gireactor = None
+else:
+    gireactor = _gireactor
+
+missingGlibReactor = None
+if gireactor is None:
+    missingGlibReactor = "gi reactor not available"
+
+
 class GlibReactorBaseTests(TestCase):
+    """
+    Tests for the private C{twisted.internet._glibbase.GlibReactorBase}
+    done via the public C{twisted.internet.gireactor.PortableGIReactor}
+    """
+    skip = missingGlibReactor
+
     def test_simulate(self):
-        """ """
-        try:
-            from twisted.internet import gireactor as _gireactor
-        except ImportError:
-            gireactor = None
-        else:
-            gireactor = _gireactor
-
-        if gireactor is None:
-            self.skipTest("gi reactor not available")
-
-        gireactor.install().simulate()
+        """
+        C{simulate} can be called without raising any errors when there are
+        no delayed calls for the reactor and hence there is no defined sleep
+        period.
+        """
+        sut = gireactor.PortableGIReactor(usegtk=False)
+        # Double check that reactor has no sleep period.
+        self.assertIs(None, sut.timeout())
+
+        sut.simulate()