1''' 2 Tests for fpformat module 3 Nick Mathewson 4''' 5from test.test_support import run_unittest, import_module 6import unittest 7fpformat = import_module('fpformat', deprecated=True) 8fix, sci, NotANumber = fpformat.fix, fpformat.sci, fpformat.NotANumber 9 10StringType = type('') 11 12# Test the old and obsolescent fpformat module. 13# 14# (It's obsolescent because fix(n,d) == "%.*f"%(d,n) and 15# sci(n,d) == "%.*e"%(d,n) 16# for all reasonable numeric n and d, except that sci gives 3 exponent 17# digits instead of 2. 18# 19# Differences only occur for unreasonable n and d. <.2 wink>) 20 21class FpformatTest(unittest.TestCase): 22 23 def checkFix(self, n, digits): 24 result = fix(n, digits) 25 if isinstance(n, StringType): 26 n = repr(n) 27 expected = "%.*f" % (digits, float(n)) 28 29 self.assertEqual(result, expected) 30 31 def checkSci(self, n, digits): 32 result = sci(n, digits) 33 if isinstance(n, StringType): 34 n = repr(n) 35 expected = "%.*e" % (digits, float(n)) 36 # add the extra 0 if needed 37 num, exp = expected.split("e") 38 if len(exp) < 4: 39 exp = exp[0] + "0" + exp[1:] 40 expected = "%se%s" % (num, exp) 41 42 self.assertEqual(result, expected) 43 44 def test_basic_cases(self): 45 self.assertEqual(fix(100.0/3, 3), '33.333') 46 self.assertEqual(sci(100.0/3, 3), '3.333e+001') 47 48 def test_reasonable_values(self): 49 for d in range(7): 50 for val in (1000.0/3, 1000, 1000.0, .002, 1.0/3, 1e10): 51 for realVal in (val, 1.0/val, -val, -1.0/val): 52 self.checkFix(realVal, d) 53 self.checkSci(realVal, d) 54 55 def test_failing_values(self): 56 # Now for 'unreasonable n and d' 57 self.assertEqual(fix(1.0, 1000), '1.'+('0'*1000)) 58 self.assertEqual(sci("1"+('0'*1000), 0), '1e+1000') 59 60 # This behavior is inconsistent. sci raises an exception; fix doesn't. 61 yacht = "Throatwobbler Mangrove" 62 self.assertEqual(fix(yacht, 10), yacht) 63 try: 64 sci(yacht, 10) 65 except NotANumber: 66 pass 67 else: 68 self.fail("No exception on non-numeric sci") 69 70 71def test_main(): 72 run_unittest(FpformatTest) 73 74 75if __name__ == "__main__": 76 test_main() 77