#21940: Add unittest for WidgetRedirector. Initial patch by Saimadhav Heblikar.

Lib/idlelib/idle_test/mock_idle.py

@@ -26,7 +26,10 @@ class Func:
         self.called = True
         self.args = args
         self.kwds = kwds
-        return self.result
+        if isinstance(self.result, BaseException):
+            raise self.result
+        else:
+            return self.result
 
 
 class Editor:

Lib/idlelib/idle_test/test_widgetredir.py

@@ -0,0 +1,122 @@
+"""Unittest for idlelib.WidgetRedirector
+
+100% coverage
+"""
+from test.support import requires
+import unittest
+from idlelib.idle_test.mock_idle import Func
+from tkinter import Tk, Text, TclError
+from idlelib.WidgetRedirector import WidgetRedirector
+
+
+class InitCloseTest(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        requires('gui')
+        cls.tk = Tk()
+        cls.text = Text(cls.tk)
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.text.destroy()
+        cls.tk.destroy()
+        del cls.text, cls.tk
+
+    def test_init(self):
+        redir = WidgetRedirector(self.text)
+        self.assertEqual(redir.widget, self.text)
+        self.assertEqual(redir.tk, self.text.tk)
+        self.assertRaises(TclError, WidgetRedirector, self.text)
+        redir.close()  # restore self.tk, self.text
+
+    def test_close(self):
+        redir = WidgetRedirector(self.text)
+        redir.register('insert', Func)
+        redir.close()
+        self.assertEqual(redir._operations, {})
+        self.assertFalse(hasattr(self.text, 'widget'))
+
+
+class WidgetRedirectorTest(unittest.TestCase):
+
+    @classmethod
+    def setUpClass(cls):
+        requires('gui')
+        cls.tk = Tk()
+        cls.text = Text(cls.tk)
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.text.destroy()
+        cls.tk.destroy()
+        del cls.text, cls.tk
+
+    def setUp(self):
+        self.redir = WidgetRedirector(self.text)
+        self.func = Func()
+        self.orig_insert = self.redir.register('insert', self.func)
+        self.text.insert('insert', 'asdf')  # leaves self.text empty
+
+    def tearDown(self):
+        self.text.delete('1.0', 'end')
+        self.redir.close()
+
+    def test_repr(self):  # partly for 100% coverage
+        self.assertIn('Redirector', repr(self.redir))
+        self.assertIn('Original', repr(self.orig_insert))
+
+    def test_register(self):
+        self.assertEqual(self.text.get('1.0', 'end'), '\n')
+        self.assertEqual(self.func.args, ('insert', 'asdf'))
+        self.assertIn('insert', self.redir._operations)
+        self.assertIn('insert', self.text.__dict__)
+        self.assertEqual(self.text.insert, self.func)
+
+    def test_original_command(self):
+        self.assertEqual(self.orig_insert.operation, 'insert')
+        self.assertEqual(self.orig_insert.tk_call, self.text.tk.call)
+        self.orig_insert('insert', 'asdf')
+        self.assertEqual(self.text.get('1.0', 'end'), 'asdf\n')
+
+    def test_unregister(self):
+        self.assertIsNone(self.redir.unregister('invalid operation name'))
+        self.assertEqual(self.redir.unregister('insert'), self.func)
+        self.assertNotIn('insert', self.redir._operations)
+        self.assertNotIn('insert', self.text.__dict__)
+
+    def test_unregister_no_attribute(self):
+        del self.text.insert
+        self.assertEqual(self.redir.unregister('insert'), self.func)
+
+    def test_dispatch_intercept(self):
+        self.func.__init__(True)
+        self.assertTrue(self.redir.dispatch('insert', False))
+        self.assertFalse(self.func.args[0])
+
+    def test_dispatch_bypass(self):
+        self.orig_insert('insert', 'asdf')
+        # tk.call returns '' where Python would return None
+        self.assertEqual(self.redir.dispatch('delete', '1.0', 'end'), '')
+        self.assertEqual(self.text.get('1.0', 'end'), '\n')
+
+    def test_dispatch_error(self):
+        self.func.__init__(TclError())
+        self.assertEqual(self.redir.dispatch('insert', False), '')
+        self.assertEqual(self.redir.dispatch('invalid'), '')
+
+    def test_command_dispatch(self):
+        # Test that .__init__ causes redirection of tk calls
+        # through redir.dispatch
+        self.tk.call(self.text._w, 'insert', 'hello')
+        self.assertEqual(self.func.args, ('hello',))
+        self.assertEqual(self.text.get('1.0', 'end'), '\n')
+        # Ensure that called through redir .dispatch and not through
+        # self.text.insert by having mock raise TclError.
+        self.func.__init__(TclError())
+        self.assertEqual(self.tk.call(self.text._w, 'insert', 'boo'), '')
+
+
+
+if __name__ == '__main__':
+    unittest.main(verbosity=2)