Patch #1675423: PyComplex_AsCComplex() now tries to convert an object
to complex using its __complex__() method before falling back to the
__float__() method. Therefore, the functions in the cmath module now
can operate on objects that define a __complex__() method.
(backport)
diff --git a/Lib/test/test_cmath.py b/Lib/test/test_cmath.py
index 6e39292..7198dae 100755
--- a/Lib/test/test_cmath.py
+++ b/Lib/test/test_cmath.py
@@ -1,52 +1,196 @@
-#! /usr/bin/env python
-""" Simple test script for cmathmodule.c
- Roger E. Masse
-"""
+from test.test_support import run_unittest
+import unittest
import cmath, math
-from test.test_support import verbose, verify, TestFailed
-verify(abs(cmath.log(10) - math.log(10)) < 1e-9)
-verify(abs(cmath.log(10,2) - math.log(10,2)) < 1e-9)
-try:
- cmath.log('a')
-except TypeError:
- pass
-else:
- raise TestFailed
+class CMathTests(unittest.TestCase):
+ # list of all functions in cmath
+ test_functions = [getattr(cmath, fname) for fname in [
+ 'acos', 'acosh', 'asin', 'asinh', 'atan', 'atanh',
+ 'cos', 'cosh', 'exp', 'log', 'log10', 'sin', 'sinh',
+ 'sqrt', 'tan', 'tanh']]
+ # test first and second arguments independently for 2-argument log
+ test_functions.append(lambda x : cmath.log(x, 1729. + 0j))
+ test_functions.append(lambda x : cmath.log(14.-27j, x))
-try:
- cmath.log(10, 'a')
-except TypeError:
- pass
-else:
- raise TestFailed
+ def cAssertAlmostEqual(self, a, b, rel_eps = 1e-10, abs_eps = 1e-100):
+ """Check that two complex numbers are almost equal."""
+ # the two complex numbers are considered almost equal if
+ # either the relative error is <= rel_eps or the absolute error
+ # is tiny, <= abs_eps.
+ if a == b == 0:
+ return
+ absolute_error = abs(a-b)
+ relative_error = absolute_error/max(abs(a), abs(b))
+ if relative_error > rel_eps and absolute_error > abs_eps:
+ self.fail("%s and %s are not almost equal" % (a, b))
+ def test_constants(self):
+ e_expected = 2.71828182845904523536
+ pi_expected = 3.14159265358979323846
+ self.assertAlmostEqual(cmath.pi, pi_expected, 9,
+ "cmath.pi is %s; should be %s" % (cmath.pi, pi_expected))
+ self.assertAlmostEqual(cmath.e, e_expected, 9,
+ "cmath.e is %s; should be %s" % (cmath.e, e_expected))
-testdict = {'acos' : 1.0,
- 'acosh' : 1.0,
- 'asin' : 1.0,
- 'asinh' : 1.0,
- 'atan' : 0.2,
- 'atanh' : 0.2,
- 'cos' : 1.0,
- 'cosh' : 1.0,
- 'exp' : 1.0,
- 'log' : 1.0,
- 'log10' : 1.0,
- 'sin' : 1.0,
- 'sinh' : 1.0,
- 'sqrt' : 1.0,
- 'tan' : 1.0,
- 'tanh' : 1.0}
+ def test_user_object(self):
+ # Test automatic calling of __complex__ and __float__ by cmath
+ # functions
-for func in testdict.keys():
- f = getattr(cmath, func)
- r = f(testdict[func])
- if verbose:
- print 'Calling %s(%f) = %f' % (func, testdict[func], abs(r))
+ # some random values to use as test values; we avoid values
+ # for which any of the functions in cmath is undefined
+ # (i.e. 0., 1., -1., 1j, -1j) or would cause overflow
+ cx_arg = 4.419414439 + 1.497100113j
+ flt_arg = -6.131677725
-p = cmath.pi
-e = cmath.e
-if verbose:
- print 'PI = ', abs(p)
- print 'E = ', abs(e)
+ # a variety of non-complex numbers, used to check that
+ # non-complex return values from __complex__ give an error
+ non_complexes = ["not complex", 1, 5L, 2., None,
+ object(), NotImplemented]
+
+ # Now we introduce a variety of classes whose instances might
+ # end up being passed to the cmath functions
+
+ # usual case: new-style class implementing __complex__
+ class MyComplex(object):
+ def __init__(self, value):
+ self.value = value
+ def __complex__(self):
+ return self.value
+
+ # old-style class implementing __complex__
+ class MyComplexOS:
+ def __init__(self, value):
+ self.value = value
+ def __complex__(self):
+ return self.value
+
+ # classes for which __complex__ raises an exception
+ class SomeException(Exception):
+ pass
+ class MyComplexException(object):
+ def __complex__(self):
+ raise SomeException
+ class MyComplexExceptionOS:
+ def __complex__(self):
+ raise SomeException
+
+ # some classes not providing __float__ or __complex__
+ class NeitherComplexNorFloat(object):
+ pass
+ class NeitherComplexNorFloatOS:
+ pass
+ class MyInt(object):
+ def __int__(self): return 2
+ def __long__(self): return 2L
+ def __index__(self): return 2
+ class MyIntOS:
+ def __int__(self): return 2
+ def __long__(self): return 2L
+ def __index__(self): return 2
+
+ # other possible combinations of __float__ and __complex__
+ # that should work
+ class FloatAndComplex(object):
+ def __float__(self):
+ return flt_arg
+ def __complex__(self):
+ return cx_arg
+ class FloatAndComplexOS:
+ def __float__(self):
+ return flt_arg
+ def __complex__(self):
+ return cx_arg
+ class JustFloat(object):
+ def __float__(self):
+ return flt_arg
+ class JustFloatOS:
+ def __float__(self):
+ return flt_arg
+
+ for f in self.test_functions:
+ # usual usage
+ self.cAssertAlmostEqual(f(MyComplex(cx_arg)), f(cx_arg))
+ self.cAssertAlmostEqual(f(MyComplexOS(cx_arg)), f(cx_arg))
+ # other combinations of __float__ and __complex__
+ self.cAssertAlmostEqual(f(FloatAndComplex()), f(cx_arg))
+ self.cAssertAlmostEqual(f(FloatAndComplexOS()), f(cx_arg))
+ self.cAssertAlmostEqual(f(JustFloat()), f(flt_arg))
+ self.cAssertAlmostEqual(f(JustFloatOS()), f(flt_arg))
+ # TypeError should be raised for classes not providing
+ # either __complex__ or __float__, even if they provide
+ # __int__, __long__ or __index__. An old-style class
+ # currently raises AttributeError instead of a TypeError;
+ # this could be considered a bug.
+ self.assertRaises(TypeError, f, NeitherComplexNorFloat())
+ self.assertRaises(TypeError, f, MyInt())
+ self.assertRaises(Exception, f, NeitherComplexNorFloatOS())
+ self.assertRaises(Exception, f, MyIntOS())
+ # non-complex return value from __complex__ -> TypeError
+ for bad_complex in non_complexes:
+ self.assertRaises(TypeError, f, MyComplex(bad_complex))
+ self.assertRaises(TypeError, f, MyComplexOS(bad_complex))
+ # exceptions in __complex__ should be propagated correctly
+ self.assertRaises(SomeException, f, MyComplexException())
+ self.assertRaises(SomeException, f, MyComplexExceptionOS())
+
+ def test_input_type(self):
+ # ints and longs should be acceptable inputs to all cmath
+ # functions, by virtue of providing a __float__ method
+ for f in self.test_functions:
+ for arg in [2, 2L, 2.]:
+ self.cAssertAlmostEqual(f(arg), f(arg.__float__()))
+
+ # but strings should give a TypeError
+ for f in self.test_functions:
+ for arg in ["a", "long_string", "0", "1j", ""]:
+ self.assertRaises(TypeError, f, arg)
+
+ def test_cmath_matches_math(self):
+ # check that corresponding cmath and math functions are equal
+ # for floats in the appropriate range
+
+ # test_values in (0, 1)
+ test_values = [0.01, 0.1, 0.2, 0.5, 0.9, 0.99]
+
+ # test_values for functions defined on [-1., 1.]
+ unit_interval = test_values + [-x for x in test_values] + \
+ [0., 1., -1.]
+
+ # test_values for log, log10, sqrt
+ positive = test_values + [1.] + [1./x for x in test_values]
+ nonnegative = [0.] + positive
+
+ # test_values for functions defined on the whole real line
+ real_line = [0.] + positive + [-x for x in positive]
+
+ test_functions = {
+ 'acos' : unit_interval,
+ 'asin' : unit_interval,
+ 'atan' : real_line,
+ 'cos' : real_line,
+ 'cosh' : real_line,
+ 'exp' : real_line,
+ 'log' : positive,
+ 'log10' : positive,
+ 'sin' : real_line,
+ 'sinh' : real_line,
+ 'sqrt' : nonnegative,
+ 'tan' : real_line,
+ 'tanh' : real_line}
+
+ for fn, values in test_functions.items():
+ float_fn = getattr(math, fn)
+ complex_fn = getattr(cmath, fn)
+ for v in values:
+ self.cAssertAlmostEqual(float_fn(v), complex_fn(v))
+
+ # test two-argument version of log with various bases
+ for base in [0.5, 2., 10.]:
+ for v in positive:
+ self.cAssertAlmostEqual(cmath.log(v, base), math.log(v, base))
+
+def test_main():
+ run_unittest(CMathTests)
+
+if __name__ == "__main__":
+ test_main()