bpo-42328: Fix tkinter.ttk.Style.map(). (GH-23300)

The function accepts now the representation of the default state as
empty sequence (as returned by Style.map()).
The structure of the result is now the same on all platform
and does not depend on the value of wantobjects.

1 files changed, 3 insertions, 4 deletions

diff --git a/Lib/tkinter/test/test_ttk/test_functions.py b/Lib/tkinter/test/test_ttk/test_functions.py
index f8e69a9f41..5c23d6fecf 100644
--- a/Lib/tkinter/test/test_ttk/test_functions.py
+++ b/Lib/tkinter/test/test_ttk/test_functions.py
@@ -137,6 +137,9 @@ class InternalFunctionsTest(unittest.TestCase):
         result = ttk._format_mapdict(opts)
         self.assertEqual(result, ('-üñíćódè', 'á vãl'))
 
+        self.assertEqual(ttk._format_mapdict({'opt': [('value',)]}),
+                         ('-opt', '{} value'))
+
         # empty states
         valid = {'opt': [('', '', 'hi')]}
         self.assertEqual(ttk._format_mapdict(valid), ('-opt', '{ } hi'))
@@ -159,10 +162,6 @@ class InternalFunctionsTest(unittest.TestCase):
         opts = {'a': None}
         self.assertRaises(TypeError, ttk._format_mapdict, opts)
 
-        # items in the value must have size >= 2
-        self.assertRaises(IndexError, ttk._format_mapdict,
-            {'a': [('invalid', )]})
-
 
     def test_format_elemcreate(self):
         self.assertTrue(ttk._format_elemcreate(None), (None, ()))