Lib/test/test_fpformat.py
''' Tests for fpformat module Nick Mathewson ''' from test.test_support import run_unittest, import_module import unittest fpformat = import_module('fpformat', deprecated=True) fix, sci, NotANumber = fpformat.fix, fpformat.sci, fpformat.NotANumber StringType = type('') # Test the old and obsolescent fpformat module. # # (It's obsolescent because fix(n,d) == "%.*f"%(d,n) and # sci(n,d) == "%.*e"%(d,n) # for all reasonable numeric n and d, except that sci gives 3 exponent # digits instead of 2. # # Differences only occur for unreasonable n and d. <.2 wink>) class FpformatTest(unittest.TestCase): def checkFix(self, n, digits): result = fix(n, digits) if isinstance(n, StringType): n = repr(n) expected = "%.*f" % (digits, float(n)) self.assertEqual(result, expected) def checkSci(self, n, digits): result = sci(n, digits) if isinstance(n, StringType): n = repr(n) expected = "%.*e" % (digits, float(n)) # add the extra 0 if needed num, exp = expected.split("e") if len(exp) < 4: exp = exp[0] + "0" + exp[1:] expected = "%se%s" % (num, exp) self.assertEqual(result, expected) def test_basic_cases(self): self.assertEqual(fix(100.0/3, 3), '33.333') self.assertEqual(sci(100.0/3, 3), '3.333e+001') def test_reasonable_values(self): for d in range(7): for val in (1000.0/3, 1000, 1000.0, .002, 1.0/3, 1e10): for realVal in (val, 1.0/val, -val, -1.0/val): self.checkFix(realVal, d) self.checkSci(realVal, d) def test_failing_values(self): # Now for 'unreasonable n and d' self.assertEqual(fix(1.0, 1000), '1.'+('0'*1000)) self.assertEqual(sci("1"+('0'*1000), 0), '1e+1000') # This behavior is inconsistent. sci raises an exception; fix doesn't. yacht = "Throatwobbler Mangrove" self.assertEqual(fix(yacht, 10), yacht) try: sci(yacht, 10) except NotANumber: pass else: self.fail("No exception on non-numeric sci") def test_main(): run_unittest(FpformatTest) if __name__ == "__main__": test_main() |