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-rw-r--r--Lib/test/test_rational.py279
1 files changed, 279 insertions, 0 deletions
diff --git a/Lib/test/test_rational.py b/Lib/test/test_rational.py
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--- /dev/null
+++ b/Lib/test/test_rational.py
@@ -0,0 +1,279 @@
+"""Tests for Lib/rational.py."""
+
+from decimal import Decimal
+from test.test_support import run_unittest, verbose
+import math
+import operator
+import rational
+import unittest
+R = rational.Rational
+
+def _components(r):
+ return (r.numerator, r.denominator)
+
+class RationalTest(unittest.TestCase):
+
+ def assertTypedEquals(self, expected, actual):
+ """Asserts that both the types and values are the same."""
+ self.assertEquals(type(expected), type(actual))
+ self.assertEquals(expected, actual)
+
+ def assertRaisesMessage(self, exc_type, message,
+ callable, *args, **kwargs):
+ """Asserts that callable(*args, **kwargs) raises exc_type(message)."""
+ try:
+ callable(*args, **kwargs)
+ except exc_type, e:
+ self.assertEquals(message, str(e))
+ else:
+ self.fail("%s not raised" % exc_type.__name__)
+
+ def testInit(self):
+ self.assertEquals((0, 1), _components(R()))
+ self.assertEquals((7, 1), _components(R(7)))
+ self.assertEquals((7, 3), _components(R(R(7, 3))))
+
+ self.assertEquals((-1, 1), _components(R(-1, 1)))
+ self.assertEquals((-1, 1), _components(R(1, -1)))
+ self.assertEquals((1, 1), _components(R(-2, -2)))
+ self.assertEquals((1, 2), _components(R(5, 10)))
+ self.assertEquals((7, 15), _components(R(7, 15)))
+ self.assertEquals((10**23, 1), _components(R(10**23)))
+
+ self.assertRaisesMessage(ZeroDivisionError, "Rational(12, 0)",
+ R, 12, 0)
+ self.assertRaises(TypeError, R, 1.5)
+ self.assertRaises(TypeError, R, 1.5 + 3j)
+
+ def testFromFloat(self):
+ self.assertRaisesMessage(
+ TypeError, "Rational.from_float() only takes floats, not 3 (int)",
+ R.from_float, 3)
+
+ self.assertEquals((0, 1), _components(R.from_float(-0.0)))
+ self.assertEquals((10, 1), _components(R.from_float(10.0)))
+ self.assertEquals((-5, 2), _components(R.from_float(-2.5)))
+ self.assertEquals((99999999999999991611392, 1),
+ _components(R.from_float(1e23)))
+ self.assertEquals(float(10**23), float(R.from_float(1e23)))
+ self.assertEquals((3602879701896397, 1125899906842624),
+ _components(R.from_float(3.2)))
+ self.assertEquals(3.2, float(R.from_float(3.2)))
+
+ inf = 1e1000
+ nan = inf - inf
+ self.assertRaisesMessage(
+ TypeError, "Cannot convert inf to Rational.",
+ R.from_float, inf)
+ self.assertRaisesMessage(
+ TypeError, "Cannot convert -inf to Rational.",
+ R.from_float, -inf)
+ self.assertRaisesMessage(
+ TypeError, "Cannot convert nan to Rational.",
+ R.from_float, nan)
+
+ def testConversions(self):
+ self.assertTypedEquals(-1, trunc(R(-11, 10)))
+ self.assertTypedEquals(-2, R(-11, 10).__floor__())
+ self.assertTypedEquals(-1, R(-11, 10).__ceil__())
+ self.assertTypedEquals(-1, R(-10, 10).__ceil__())
+
+ self.assertTypedEquals(0, R(-1, 10).__round__())
+ self.assertTypedEquals(0, R(-5, 10).__round__())
+ self.assertTypedEquals(-2, R(-15, 10).__round__())
+ self.assertTypedEquals(-1, R(-7, 10).__round__())
+
+ self.assertEquals(False, bool(R(0, 1)))
+ self.assertEquals(True, bool(R(3, 2)))
+ self.assertTypedEquals(0.1, float(R(1, 10)))
+
+ # Check that __float__ isn't implemented by converting the
+ # numerator and denominator to float before dividing.
+ self.assertRaises(OverflowError, float, long('2'*400+'7'))
+ self.assertAlmostEquals(2.0/3,
+ float(R(long('2'*400+'7'), long('3'*400+'1'))))
+
+ self.assertTypedEquals(0.1+0j, complex(R(1,10)))
+
+ def testRound(self):
+ self.assertTypedEquals(R(-200), R(-150).__round__(-2))
+ self.assertTypedEquals(R(-200), R(-250).__round__(-2))
+ self.assertTypedEquals(R(30), R(26).__round__(-1))
+ self.assertTypedEquals(R(-2, 10), R(-15, 100).__round__(1))
+ self.assertTypedEquals(R(-2, 10), R(-25, 100).__round__(1))
+
+
+ def testArithmetic(self):
+ self.assertEquals(R(1, 2), R(1, 10) + R(2, 5))
+ self.assertEquals(R(-3, 10), R(1, 10) - R(2, 5))
+ self.assertEquals(R(1, 25), R(1, 10) * R(2, 5))
+ self.assertEquals(R(1, 4), R(1, 10) / R(2, 5))
+ self.assertTypedEquals(2, R(9, 10) // R(2, 5))
+ self.assertTypedEquals(10**23, R(10**23, 1) // R(1))
+ self.assertEquals(R(2, 3), R(-7, 3) % R(3, 2))
+ self.assertEquals(R(8, 27), R(2, 3) ** R(3))
+ self.assertEquals(R(27, 8), R(2, 3) ** R(-3))
+ self.assertTypedEquals(2.0, R(4) ** R(1, 2))
+ # Will return 1j in 3.0:
+ self.assertRaises(ValueError, pow, R(-1), R(1, 2))
+
+ def testMixedArithmetic(self):
+ self.assertTypedEquals(R(11, 10), R(1, 10) + 1)
+ self.assertTypedEquals(1.1, R(1, 10) + 1.0)
+ self.assertTypedEquals(1.1 + 0j, R(1, 10) + (1.0 + 0j))
+ self.assertTypedEquals(R(11, 10), 1 + R(1, 10))
+ self.assertTypedEquals(1.1, 1.0 + R(1, 10))
+ self.assertTypedEquals(1.1 + 0j, (1.0 + 0j) + R(1, 10))
+
+ self.assertTypedEquals(R(-9, 10), R(1, 10) - 1)
+ self.assertTypedEquals(-0.9, R(1, 10) - 1.0)
+ self.assertTypedEquals(-0.9 + 0j, R(1, 10) - (1.0 + 0j))
+ self.assertTypedEquals(R(9, 10), 1 - R(1, 10))
+ self.assertTypedEquals(0.9, 1.0 - R(1, 10))
+ self.assertTypedEquals(0.9 + 0j, (1.0 + 0j) - R(1, 10))
+
+ self.assertTypedEquals(R(1, 10), R(1, 10) * 1)
+ self.assertTypedEquals(0.1, R(1, 10) * 1.0)
+ self.assertTypedEquals(0.1 + 0j, R(1, 10) * (1.0 + 0j))
+ self.assertTypedEquals(R(1, 10), 1 * R(1, 10))
+ self.assertTypedEquals(0.1, 1.0 * R(1, 10))
+ self.assertTypedEquals(0.1 + 0j, (1.0 + 0j) * R(1, 10))
+
+ self.assertTypedEquals(R(1, 10), R(1, 10) / 1)
+ self.assertTypedEquals(0.1, R(1, 10) / 1.0)
+ self.assertTypedEquals(0.1 + 0j, R(1, 10) / (1.0 + 0j))
+ self.assertTypedEquals(R(10, 1), 1 / R(1, 10))
+ self.assertTypedEquals(10.0, 1.0 / R(1, 10))
+ self.assertTypedEquals(10.0 + 0j, (1.0 + 0j) / R(1, 10))
+
+ self.assertTypedEquals(0, R(1, 10) // 1)
+ self.assertTypedEquals(0.0, R(1, 10) // 1.0)
+ self.assertTypedEquals(10, 1 // R(1, 10))
+ self.assertTypedEquals(10**23, 10**22 // R(1, 10))
+ self.assertTypedEquals(10.0, 1.0 // R(1, 10))
+
+ self.assertTypedEquals(R(1, 10), R(1, 10) % 1)
+ self.assertTypedEquals(0.1, R(1, 10) % 1.0)
+ self.assertTypedEquals(R(0, 1), 1 % R(1, 10))
+ self.assertTypedEquals(0.0, 1.0 % R(1, 10))
+
+ # No need for divmod since we don't override it.
+
+ # ** has more interesting conversion rules.
+ self.assertTypedEquals(R(100, 1), R(1, 10) ** -2)
+ self.assertTypedEquals(R(100, 1), R(10, 1) ** 2)
+ self.assertTypedEquals(0.1, R(1, 10) ** 1.0)
+ self.assertTypedEquals(0.1 + 0j, R(1, 10) ** (1.0 + 0j))
+ self.assertTypedEquals(4 , 2 ** R(2, 1))
+ # Will return 1j in 3.0:
+ self.assertRaises(ValueError, pow, (-1), R(1, 2))
+ self.assertTypedEquals(R(1, 4) , 2 ** R(-2, 1))
+ self.assertTypedEquals(2.0 , 4 ** R(1, 2))
+ self.assertTypedEquals(0.25, 2.0 ** R(-2, 1))
+ self.assertTypedEquals(1.0 + 0j, (1.0 + 0j) ** R(1, 10))
+
+ def testMixingWithDecimal(self):
+ """Decimal refuses mixed comparisons."""
+ self.assertRaisesMessage(
+ TypeError,
+ "unsupported operand type(s) for +: 'Rational' and 'Decimal'",
+ operator.add, R(3,11), Decimal('3.1415926'))
+ self.assertNotEquals(R(5, 2), Decimal('2.5'))
+
+ def testComparisons(self):
+ self.assertTrue(R(1, 2) < R(2, 3))
+ self.assertFalse(R(1, 2) < R(1, 2))
+ self.assertTrue(R(1, 2) <= R(2, 3))
+ self.assertTrue(R(1, 2) <= R(1, 2))
+ self.assertFalse(R(2, 3) <= R(1, 2))
+ self.assertTrue(R(1, 2) == R(1, 2))
+ self.assertFalse(R(1, 2) == R(1, 3))
+
+ def testMixedLess(self):
+ self.assertTrue(2 < R(5, 2))
+ self.assertFalse(2 < R(4, 2))
+ self.assertTrue(R(5, 2) < 3)
+ self.assertFalse(R(4, 2) < 2)
+
+ self.assertTrue(R(1, 2) < 0.6)
+ self.assertFalse(R(1, 2) < 0.4)
+ self.assertTrue(0.4 < R(1, 2))
+ self.assertFalse(0.5 < R(1, 2))
+
+ def testMixedLessEqual(self):
+ self.assertTrue(0.5 <= R(1, 2))
+ self.assertFalse(0.6 <= R(1, 2))
+ self.assertTrue(R(1, 2) <= 0.5)
+ self.assertFalse(R(1, 2) <= 0.4)
+ self.assertTrue(2 <= R(4, 2))
+ self.assertFalse(2 <= R(3, 2))
+ self.assertTrue(R(4, 2) <= 2)
+ self.assertFalse(R(5, 2) <= 2)
+
+ def testBigFloatComparisons(self):
+ # Because 10**23 can't be represented exactly as a float:
+ self.assertFalse(R(10**23) == float(10**23))
+ # The first test demonstrates why these are important.
+ self.assertFalse(1e23 < float(R(trunc(1e23) + 1)))
+ self.assertTrue(1e23 < R(trunc(1e23) + 1))
+ self.assertFalse(1e23 <= R(trunc(1e23) - 1))
+ self.assertTrue(1e23 > R(trunc(1e23) - 1))
+ self.assertFalse(1e23 >= R(trunc(1e23) + 1))
+
+ def testBigComplexComparisons(self):
+ self.assertFalse(R(10**23) == complex(10**23))
+ self.assertTrue(R(10**23) > complex(10**23))
+ self.assertFalse(R(10**23) <= complex(10**23))
+
+ def testMixedEqual(self):
+ self.assertTrue(0.5 == R(1, 2))
+ self.assertFalse(0.6 == R(1, 2))
+ self.assertTrue(R(1, 2) == 0.5)
+ self.assertFalse(R(1, 2) == 0.4)
+ self.assertTrue(2 == R(4, 2))
+ self.assertFalse(2 == R(3, 2))
+ self.assertTrue(R(4, 2) == 2)
+ self.assertFalse(R(5, 2) == 2)
+
+ def testStringification(self):
+ self.assertEquals("rational.Rational(7,3)", repr(R(7, 3)))
+ self.assertEquals("(7/3)", str(R(7, 3)))
+ self.assertEquals("7", str(R(7, 1)))
+
+ def testHash(self):
+ self.assertEquals(hash(2.5), hash(R(5, 2)))
+ self.assertEquals(hash(10**50), hash(R(10**50)))
+ self.assertNotEquals(hash(float(10**23)), hash(R(10**23)))
+
+ def testApproximatePi(self):
+ # Algorithm borrowed from
+ # http://docs.python.org/lib/decimal-recipes.html
+ three = R(3)
+ lasts, t, s, n, na, d, da = 0, three, 3, 1, 0, 0, 24
+ while abs(s - lasts) > R(1, 10**9):
+ lasts = s
+ n, na = n+na, na+8
+ d, da = d+da, da+32
+ t = (t * n) / d
+ s += t
+ self.assertAlmostEquals(math.pi, s)
+
+ def testApproximateCos1(self):
+ # Algorithm borrowed from
+ # http://docs.python.org/lib/decimal-recipes.html
+ x = R(1)
+ i, lasts, s, fact, num, sign = 0, 0, R(1), 1, 1, 1
+ while abs(s - lasts) > R(1, 10**9):
+ lasts = s
+ i += 2
+ fact *= i * (i-1)
+ num *= x * x
+ sign *= -1
+ s += num / fact * sign
+ self.assertAlmostEquals(math.cos(1), s)
+
+def test_main():
+ run_unittest(RationalTest)
+
+if __name__ == '__main__':
+ test_main()
generated by cgit v0.12 at 2024-10-23 03:19:58 (GMT)