diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/random.py | 53 | ||||
| -rw-r--r-- | Lib/test/test_random.py | 80 |
2 files changed, 47 insertions, 86 deletions
diff --git a/Lib/random.py b/Lib/random.py index 1f3530e..a2dfcb5 100644 --- a/Lib/random.py +++ b/Lib/random.py @@ -282,67 +282,34 @@ class Random(_random.Random): ## -------------------- integer methods ------------------- def randrange(self, start, stop=None, step=_ONE): - """Choose a random item from range(start, stop[, step]). + """Choose a random item from range(stop) or range(start, stop[, step]). - This fixes the problem with randint() which includes the - endpoint; in Python this is usually not what you want. + Roughly equivalent to ``choice(range(start, stop, step))`` but + supports arbitrarily large ranges and is optimized for common cases. """ # This code is a bit messy to make it fast for the # common case while still doing adequate error checking. - try: - istart = _index(start) - except TypeError: - istart = int(start) - if istart != start: - _warn('randrange() will raise TypeError in the future', - DeprecationWarning, 2) - raise ValueError("non-integer arg 1 for randrange()") - _warn('non-integer arguments to randrange() have been deprecated ' - 'since Python 3.10 and will be removed in a subsequent ' - 'version', - DeprecationWarning, 2) + istart = _index(start) if stop is None: # We don't check for "step != 1" because it hasn't been # type checked and converted to an integer yet. if step is not _ONE: - raise TypeError('Missing a non-None stop argument') + raise TypeError("Missing a non-None stop argument") if istart > 0: return self._randbelow(istart) raise ValueError("empty range for randrange()") - # stop argument supplied. - try: - istop = _index(stop) - except TypeError: - istop = int(stop) - if istop != stop: - _warn('randrange() will raise TypeError in the future', - DeprecationWarning, 2) - raise ValueError("non-integer stop for randrange()") - _warn('non-integer arguments to randrange() have been deprecated ' - 'since Python 3.10 and will be removed in a subsequent ' - 'version', - DeprecationWarning, 2) + # Stop argument supplied. + istop = _index(stop) width = istop - istart - try: - istep = _index(step) - except TypeError: - istep = int(step) - if istep != step: - _warn('randrange() will raise TypeError in the future', - DeprecationWarning, 2) - raise ValueError("non-integer step for randrange()") - _warn('non-integer arguments to randrange() have been deprecated ' - 'since Python 3.10 and will be removed in a subsequent ' - 'version', - DeprecationWarning, 2) + istep = _index(step) # Fast path. if istep == 1: if width > 0: return istart + self._randbelow(width) - raise ValueError("empty range for randrange() (%d, %d, %d)" % (istart, istop, width)) + raise ValueError(f"empty range in randrange({start}, {stop})") # Non-unit step argument supplied. if istep > 0: @@ -352,7 +319,7 @@ class Random(_random.Random): else: raise ValueError("zero step for randrange()") if n <= 0: - raise ValueError("empty range for randrange()") + raise ValueError(f"empty range in randrange({start}, {stop}, {step})") return istart + istep * self._randbelow(n) def randint(self, a, b): diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py index 32e7868..fcf17a9 100644 --- a/Lib/test/test_random.py +++ b/Lib/test/test_random.py @@ -485,50 +485,44 @@ class SystemRandom_TestBasicOps(TestBasicOps, unittest.TestCase): self.assertEqual(rint, 0) def test_randrange_errors(self): - raises = partial(self.assertRaises, ValueError, self.gen.randrange) + raises_value_error = partial(self.assertRaises, ValueError, self.gen.randrange) + raises_type_error = partial(self.assertRaises, TypeError, self.gen.randrange) + # Empty range - raises(3, 3) - raises(-721) - raises(0, 100, -12) - # Non-integer start/stop - self.assertWarns(DeprecationWarning, raises, 3.14159) - self.assertWarns(DeprecationWarning, self.gen.randrange, 3.0) - self.assertWarns(DeprecationWarning, self.gen.randrange, Fraction(3, 1)) - self.assertWarns(DeprecationWarning, raises, '3') - self.assertWarns(DeprecationWarning, raises, 0, 2.71828) - self.assertWarns(DeprecationWarning, self.gen.randrange, 0, 2.0) - self.assertWarns(DeprecationWarning, self.gen.randrange, 0, Fraction(2, 1)) - self.assertWarns(DeprecationWarning, raises, 0, '2') - # Zero and non-integer step - raises(0, 42, 0) - self.assertWarns(DeprecationWarning, raises, 0, 42, 0.0) - self.assertWarns(DeprecationWarning, raises, 0, 0, 0.0) - self.assertWarns(DeprecationWarning, raises, 0, 42, 3.14159) - self.assertWarns(DeprecationWarning, self.gen.randrange, 0, 42, 3.0) - self.assertWarns(DeprecationWarning, self.gen.randrange, 0, 42, Fraction(3, 1)) - self.assertWarns(DeprecationWarning, raises, 0, 42, '3') - self.assertWarns(DeprecationWarning, self.gen.randrange, 0, 42, 1.0) - self.assertWarns(DeprecationWarning, raises, 0, 0, 1.0) - - def test_randrange_argument_handling(self): - randrange = self.gen.randrange - with self.assertWarns(DeprecationWarning): - randrange(10.0, 20, 2) - with self.assertWarns(DeprecationWarning): - randrange(10, 20.0, 2) - with self.assertWarns(DeprecationWarning): - randrange(10, 20, 1.0) - with self.assertWarns(DeprecationWarning): - randrange(10, 20, 2.0) - with self.assertWarns(DeprecationWarning): - with self.assertRaises(ValueError): - randrange(10.5) - with self.assertWarns(DeprecationWarning): - with self.assertRaises(ValueError): - randrange(10, 20.5) - with self.assertWarns(DeprecationWarning): - with self.assertRaises(ValueError): - randrange(10, 20, 1.5) + raises_value_error(3, 3) + raises_value_error(-721) + raises_value_error(0, 100, -12) + + # Zero step + raises_value_error(0, 42, 0) + raises_type_error(0, 42, 0.0) + raises_type_error(0, 0, 0.0) + + # Non-integer stop + raises_type_error(3.14159) + raises_type_error(3.0) + raises_type_error(Fraction(3, 1)) + raises_type_error('3') + raises_type_error(0, 2.71827) + raises_type_error(0, 2.0) + raises_type_error(0, Fraction(2, 1)) + raises_type_error(0, '2') + raises_type_error(0, 2.71827, 2) + + # Non-integer start + raises_type_error(2.71827, 5) + raises_type_error(2.0, 5) + raises_type_error(Fraction(2, 1), 5) + raises_type_error('2', 5) + raises_type_error(2.71827, 5, 2) + + # Non-integer step + raises_type_error(0, 42, 3.14159) + raises_type_error(0, 42, 3.0) + raises_type_error(0, 42, Fraction(3, 1)) + raises_type_error(0, 42, '3') + raises_type_error(0, 42, 1.0) + raises_type_error(0, 0, 1.0) def test_randrange_step(self): # bpo-42772: When stop is None, the step argument was being ignored. |