...

1 files changed, 143 insertions, 0 deletions

diff --git a/src/python/stdlib/test/test_xrange.py b/src/python/stdlib/test/test_xrange.py
new file mode 100644
index 0000000..e3c799e
--- /dev/null
+++ b/src/python/stdlib/test/test_xrange.py
@@ -0,0 +1,143 @@
+# Python test set -- built-in functions
+
+import test.test_support, unittest
+import sys
+import pickle
+import itertools
+
+import warnings
+warnings.filterwarnings("ignore", "integer argument expected",
+                        DeprecationWarning, "unittest")
+
+# pure Python implementations (3 args only), for comparison
+def pyrange(start, stop, step):
+    if (start - stop) // step < 0:
+        # replace stop with next element in the sequence of integers
+        # that are congruent to start modulo step.
+        stop += (start - stop) % step
+        while start != stop:
+            yield start
+            start += step
+
+def pyrange_reversed(start, stop, step):
+    stop += (start - stop) % step
+    return pyrange(stop - step, start - step, -step)
+
+
+class XrangeTest(unittest.TestCase):
+    def assert_iterators_equal(self, xs, ys, test_id, limit=None):
+        # check that an iterator xs matches the expected results ys,
+        # up to a given limit.
+        if limit is not None:
+            xs = itertools.islice(xs, limit)
+            ys = itertools.islice(ys, limit)
+        sentinel = object()
+        pairs = itertools.izip_longest(xs, ys, fillvalue=sentinel)
+        for i, (x, y) in enumerate(pairs):
+            if x == y:
+                continue
+            elif x == sentinel:
+                self.fail('{}: iterator ended unexpectedly '
+                          'at position {}; expected {}'.format(test_id, i, y))
+            elif y == sentinel:
+                self.fail('{}: unexpected excess element {} at '
+                          'position {}'.format(test_id, x, i))
+            else:
+                self.fail('{}: wrong element at position {};'
+                          'expected {}, got {}'.format(test_id, i, y, x))
+
+    def test_xrange(self):
+        self.assertEqual(list(xrange(3)), [0, 1, 2])
+        self.assertEqual(list(xrange(1, 5)), [1, 2, 3, 4])
+        self.assertEqual(list(xrange(0)), [])
+        self.assertEqual(list(xrange(-3)), [])
+        self.assertEqual(list(xrange(1, 10, 3)), [1, 4, 7])
+        self.assertEqual(list(xrange(5, -5, -3)), [5, 2, -1, -4])
+
+        a = 10
+        b = 100
+        c = 50
+
+        self.assertEqual(list(xrange(a, a+2)), [a, a+1])
+        self.assertEqual(list(xrange(a+2, a, -1L)), [a+2, a+1])
+        self.assertEqual(list(xrange(a+4, a, -2)), [a+4, a+2])
+
+        seq = list(xrange(a, b, c))
+        self.assertIn(a, seq)
+        self.assertNotIn(b, seq)
+        self.assertEqual(len(seq), 2)
+
+        seq = list(xrange(b, a, -c))
+        self.assertIn(b, seq)
+        self.assertNotIn(a, seq)
+        self.assertEqual(len(seq), 2)
+
+        seq = list(xrange(-a, -b, -c))
+        self.assertIn(-a, seq)
+        self.assertNotIn(-b, seq)
+        self.assertEqual(len(seq), 2)
+
+        self.assertRaises(TypeError, xrange)
+        self.assertRaises(TypeError, xrange, 1, 2, 3, 4)
+        self.assertRaises(ValueError, xrange, 1, 2, 0)
+
+        self.assertRaises(OverflowError, xrange, 10**100, 10**101, 10**101)
+
+        self.assertRaises(TypeError, xrange, 0, "spam")
+        self.assertRaises(TypeError, xrange, 0, 42, "spam")
+
+        self.assertEqual(len(xrange(0, sys.maxint, sys.maxint-1)), 2)
+
+        self.assertRaises(OverflowError, xrange, -sys.maxint, sys.maxint)
+        self.assertRaises(OverflowError, xrange, 0, 2*sys.maxint)
+
+        r = xrange(-sys.maxint, sys.maxint, 2)
+        self.assertEqual(len(r), sys.maxint)
+        self.assertRaises(OverflowError, xrange, -sys.maxint-1, sys.maxint, 2)
+
+    def test_pickling(self):
+        testcases = [(13,), (0, 11), (-22, 10), (20, 3, -1),
+                     (13, 21, 3), (-2, 2, 2)]
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            for t in testcases:
+                r = xrange(*t)
+                self.assertEqual(list(pickle.loads(pickle.dumps(r, proto))),
+                                 list(r))
+
+    def test_range_iterators(self):
+        # see issue 7298
+        limits = [base + jiggle
+                  for M in (2**32, 2**64)
+                  for base in (-M, -M//2, 0, M//2, M)
+                  for jiggle in (-2, -1, 0, 1, 2)]
+        test_ranges = [(start, end, step)
+                       for start in limits
+                       for end in limits
+                       for step in (-2**63, -2**31, -2, -1, 1, 2)]
+
+        for start, end, step in test_ranges:
+            try:
+                iter1 = xrange(start, end, step)
+            except OverflowError:
+                pass
+            else:
+                iter2 = pyrange(start, end, step)
+                test_id = "xrange({}, {}, {})".format(start, end, step)
+                # check first 100 entries
+                self.assert_iterators_equal(iter1, iter2, test_id, limit=100)
+
+            try:
+                iter1 = reversed(xrange(start, end, step))
+            except OverflowError:
+                pass
+            else:
+                iter2 = pyrange_reversed(start, end, step)
+                test_id = "reversed(xrange({}, {}, {}))".format(start, end, step)
+                self.assert_iterators_equal(iter1, iter2, test_id, limit=100)
+
+
+def test_main():
+    test.test_support.run_unittest(XrangeTest)
+
+if __name__ == "__main__":
+    test_main()