diff options
Diffstat (limited to 'Lib/test/test_builtin.py')
-rw-r--r-- | Lib/test/test_builtin.py | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/Lib/test/test_builtin.py b/Lib/test/test_builtin.py index 35b652b..f00091b 100644 --- a/Lib/test/test_builtin.py +++ b/Lib/test/test_builtin.py @@ -1279,6 +1279,116 @@ class BuiltinTest(unittest.TestCase): return i self.assertRaises(ValueError, list, zip(BadSeq(), BadSeq())) + def test_format(self): + # Test the basic machinery of the format() builtin. Don't test + # the specifics of the various formatters + self.assertEqual(format(3, ''), '3') + + # Returns some classes to use for various tests. There's + # an old-style version, and a new-style version + def classes_new(): + class A(object): + def __init__(self, x): + self.x = x + def __format__(self, format_spec): + return str(self.x) + format_spec + class DerivedFromA(A): + pass + + class Simple(object): pass + class DerivedFromSimple(Simple): + def __init__(self, x): + self.x = x + def __format__(self, format_spec): + return str(self.x) + format_spec + class DerivedFromSimple2(DerivedFromSimple): pass + return A, DerivedFromA, DerivedFromSimple, DerivedFromSimple2 + + def class_test(A, DerivedFromA, DerivedFromSimple, DerivedFromSimple2): + self.assertEqual(format(A(3), 'spec'), '3spec') + self.assertEqual(format(DerivedFromA(4), 'spec'), '4spec') + self.assertEqual(format(DerivedFromSimple(5), 'abc'), '5abc') + self.assertEqual(format(DerivedFromSimple2(10), 'abcdef'), + '10abcdef') + + class_test(*classes_new()) + + def empty_format_spec(value): + # test that: + # format(x, '') == str(x) + # format(x) == str(x) + self.assertEqual(format(value, ""), str(value)) + self.assertEqual(format(value), str(value)) + + # for builtin types, format(x, "") == str(x) + empty_format_spec(17**13) + empty_format_spec(1.0) + empty_format_spec(3.1415e104) + empty_format_spec(-3.1415e104) + empty_format_spec(3.1415e-104) + empty_format_spec(-3.1415e-104) + empty_format_spec(object) + empty_format_spec(None) + + # TypeError because self.__format__ returns the wrong type + class BadFormatResult: + def __format__(self, format_spec): + return 1.0 + self.assertRaises(TypeError, format, BadFormatResult(), "") + + # TypeError because format_spec is not unicode or str + self.assertRaises(TypeError, format, object(), 4) + self.assertRaises(TypeError, format, object(), object()) + + # tests for object.__format__ really belong elsewhere, but + # there's no good place to put them + x = object().__format__('') + self.assertTrue(x.startswith('<object object at')) + + # first argument to object.__format__ must be string + self.assertRaises(TypeError, object().__format__, 3) + self.assertRaises(TypeError, object().__format__, object()) + self.assertRaises(TypeError, object().__format__, None) + + # -------------------------------------------------------------------- + # Issue #7994: object.__format__ with a non-empty format string is + # pending deprecated + def test_deprecated_format_string(obj, fmt_str, should_raise_warning): + with warnings.catch_warnings(record=True) as w: + warnings.simplefilter("always", PendingDeprecationWarning) + format(obj, fmt_str) + if should_raise_warning: + self.assertEqual(len(w), 1) + self.assertIsInstance(w[0].message, PendingDeprecationWarning) + self.assertIn('object.__format__ with a non-empty format ' + 'string', str(w[0].message)) + else: + self.assertEqual(len(w), 0) + + fmt_strs = ['', 's'] + + class A: + def __format__(self, fmt_str): + return format('', fmt_str) + + for fmt_str in fmt_strs: + test_deprecated_format_string(A(), fmt_str, False) + + class B: + pass + + class C(object): + pass + + for cls in [object, B, C]: + for fmt_str in fmt_strs: + test_deprecated_format_string(cls(), fmt_str, len(fmt_str) != 0) + # -------------------------------------------------------------------- + + # make sure we can take a subclass of str as a format spec + class DerivedFromStr(str): pass + self.assertEqual(format(0, DerivedFromStr('10')), ' 0') + def test_bin(self): self.assertEqual(bin(0), '0b0') self.assertEqual(bin(1), '0b1') |