gh-97928: Add tests for tkinter.Text.count() (GH-98269)

(cherry picked from commit 1b684c8)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

Author: miss-islington

Lib/tkinter/test/test_tkinter/test_text.py

@@ -40,6 +40,60 @@ def test_search(self):
         self.assertEqual(text.search('-test', '1.0', 'end'), '1.2')
         self.assertEqual(text.search('test', '1.0', 'end'), '1.3')
 
+    def test_count(self):
+        # XXX Some assertions do not check against the intended result,
+        # but instead check the current result to prevent regression.
+        text = self.text
+        text.insert('1.0',
+            'Lorem ipsum dolor sit amet,\n'
+            'consectetur adipiscing elit,\n'
+            'sed do eiusmod tempor incididunt\n'
+            'ut labore et dolore magna aliqua.')
+
+        options = ('chars', 'indices', 'lines',
+                   'displaychars', 'displayindices', 'displaylines',
+                   'xpixels', 'ypixels')
+        if self.wantobjects:
+            self.assertEqual(len(text.count('1.0', 'end', *options)), 8)
+        else:
+            text.count('1.0', 'end', *options)
+        self.assertEqual(text.count('1.0', 'end', 'chars', 'lines'), (124, 4)
+                         if self.wantobjects else '124 4')
+        self.assertEqual(text.count('1.3', '4.5', 'chars', 'lines'), (92, 3)
+                         if self.wantobjects else '92 3')
+        self.assertEqual(text.count('4.5', '1.3', 'chars', 'lines'), (-92, -3)
+                         if self.wantobjects else '-92 -3')
+        self.assertEqual(text.count('1.3', '1.3', 'chars', 'lines'), (0, 0)
+                         if self.wantobjects else '0 0')
+        self.assertEqual(text.count('1.0', 'end', 'lines'), (4,)
+                         if self.wantobjects else ('4',))
+        self.assertEqual(text.count('end', '1.0', 'lines'), (-4,)
+                         if self.wantobjects else ('-4',))
+        self.assertEqual(text.count('1.3', '1.5', 'lines'), None
+                         if self.wantobjects else ('0',))
+        self.assertEqual(text.count('1.3', '1.3', 'lines'), None
+                         if self.wantobjects else ('0',))
+        self.assertEqual(text.count('1.0', 'end'), (124,)  # 'indices' by default
+                         if self.wantobjects else ('124',))
+        self.assertRaises(tkinter.TclError, text.count, '1.0', 'end', 'spam')
+        # '-lines' is ignored, 'indices' is used by default
+        self.assertEqual(text.count('1.0', 'end', '-lines'), (124,)
+                         if self.wantobjects else ('124',))
+
+        self.assertIsInstance(text.count('1.3', '1.5', 'ypixels'), tuple)
+        self.assertIsInstance(text.count('1.3', '1.5', 'update', 'ypixels'), int
+                              if self.wantobjects else str)
+        self.assertEqual(text.count('1.3', '1.3', 'update', 'ypixels'), None
+                         if self.wantobjects else '0')
+        self.assertEqual(text.count('1.3', '1.5', 'update', 'indices'), 2
+                         if self.wantobjects else '2')
+        self.assertEqual(text.count('1.3', '1.3', 'update', 'indices'), None
+                         if self.wantobjects else '0')
+        self.assertEqual(text.count('1.3', '1.5', 'update'), (2,)
+                         if self.wantobjects else ('2',))
+        self.assertEqual(text.count('1.3', '1.3', 'update'), None
+                         if self.wantobjects else ('0',))
+
 
 if __name__ == "__main__":
     unittest.main()