backed out 86ba41b7bb46 (#18910) for test breakage

Lib/idlelib/idle_test/test_textview.py

-'''Test the functions and main class method of textView.py.
-
-Since all methods and functions create (or destroy) a TextViewer, which
-is a widget containing multiple widgets, all tests must be gui tests.
-Using mock Text would not change this.  Other mocks are used to retrieve
-information about calls.
-
-The coverage is essentially 100%.
-'''
-from test.test_support import requires
-requires('gui')
+'''Test the functions and main class method of textView.py.'''
 
 import unittest
 import os
+from test.test_support import requires
 from Tkinter import Tk, Text, TclError
 from idlelib import textView as tv
 from idlelib.idle_test.mock_idle import Func
 from idlelib.idle_test.mock_tk import Mbox
 
-def setUpModule():
-    global root
-    root = Tk()
-
-def tearDownModule():
-    global root
-    root.destroy()
-    del root
+orig_mbox = tv.tkMessageBox
 
+class textviewClassTest(unittest.TestCase):
 
-class TV(tv.TextViewer):  # used by TextViewTest
-    transient = Func()
-    grab_set = Func()
-    wait_window = Func()
+    @classmethod
+    def setUpClass(cls):
+        requires('gui')
+        cls.root = Tk()
+        cls.TV = TV = tv.TextViewer
+        TV.transient = Func()
+        TV.grab_set = Func()
+        TV.wait_window = Func()
 
-class TextViewTest(unittest.TestCase):
+    @classmethod
+    def tearDownClass(cls):
+        cls.root.destroy()
+        TV = cls.TV
+        del cls.root, cls.TV
+        del TV.transient, TV.grab_set, TV.wait_window
 
     def setUp(self):
+        TV = self.TV
         TV.transient.__init__()
         TV.grab_set.__init__()
         TV.wait_window.__init__()
 
+
     def test_init_modal(self):
-        view = TV(root, 'Title', 'test text')
+        TV = self.TV
+        view = TV(self.root, 'Title', 'test text')
         self.assertTrue(TV.transient.called)
         self.assertTrue(TV.grab_set.called)
         self.assertTrue(TV.wait_window.called)
         view.Ok()
 
     def test_init_nonmodal(self):
-        view = TV(root, 'Title', 'test text', modal=False)
+        TV = self.TV
+        view = TV(self.root, 'Title', 'test text', modal=False)
         self.assertFalse(TV.transient.called)
         self.assertFalse(TV.grab_set.called)
         self.assertFalse(TV.wait_window.called)
         view.Ok()
 
     def test_ok(self):
-        view = TV(root, 'Title', 'test text', modal=False)
+        view = self.TV(self.root, 'Title', 'test text', modal=False)
         view.destroy = Func()
         view.Ok()
         self.assertTrue(view.destroy.called)
@@ -66,32 +64,35 @@ class textviewTest(unittest.TestCase):
 
     @classmethod
     def setUpClass(cls):
-        cls.orig_mbox = tv.tkMessageBox
+        requires('gui')
+        cls.root = Tk()
         tv.tkMessageBox = Mbox
 
     @classmethod
     def tearDownClass(cls):
-        tv.tkMessageBox = cls.orig_mbox
-        del cls.orig_mbox
+        cls.root.destroy()
+        del cls.root
+        tv.tkMessageBox = orig_mbox
 
     def test_view_text(self):
         # If modal True, tkinter will error with 'can't invoke "event" command'
-        view = tv.view_text(root, 'Title', 'test text', modal=False)
+        view = tv.view_text(self.root, 'Title', 'test text', modal=False)
         self.assertIsInstance(view, tv.TextViewer)
 
     def test_view_file(self):
         test_dir = os.path.dirname(__file__)
         testfile = os.path.join(test_dir, 'test_textview.py')
-        view = tv.view_file(root, 'Title', testfile, modal=False)
+        view = tv.view_file(self.root, 'Title', testfile, modal=False)
         self.assertIsInstance(view, tv.TextViewer)
         self.assertIn('Test', view.textView.get('1.0', '1.end'))
         view.Ok()
 
         # Mock messagebox will be used and view_file will not return anything
         testfile = os.path.join(test_dir, '../notthere.py')
-        view = tv.view_file(root, 'Title', testfile, modal=False)
+        view = tv.view_file(self.root, 'Title', testfile, modal=False)
         self.assertIsNone(view)
 
-
 if __name__ == '__main__':
-    unittest.main(verbosity=2)
+    unittest.main(verbosity=2, exit=False)
+    from idlelib.idle_test.htest import run
+    run(TextViewer)