Lib/test/test_univnewlines.py

   1 # Tests universal newline support for both reading and parsing files.
   2 import io
   3 import _pyio as pyio
   4 import unittest
   5 import os
   6 import sys
   7 from test import support
   8
   9 if not hasattr(sys.stdin, 'newlines'):
  10     raise unittest.SkipTest(
  11         "This Python does not have universal newline support")
  12
  13 FATX = 'x' * (2**14)
  14
  15 DATA_TEMPLATE = [
  16     "line1=1",
  17     "line2='this is a very long line designed to go past any default " +
  18         "buffer limits that exist in io.py but we also want to test " +
  19         "the uncommon case, naturally.'",
  20     "def line3():pass",
  21     "line4 = '%s'" % FATX,
  22     ]
  23
  24 DATA_LF = "\n".join(DATA_TEMPLATE) + "\n"
  25 DATA_CR = "\r".join(DATA_TEMPLATE) + "\r"
  26 DATA_CRLF = "\r\n".join(DATA_TEMPLATE) + "\r\n"
  27
  28 # Note that DATA_MIXED also tests the ability to recognize a lone \r
  29 # before end-of-file.
  30 DATA_MIXED = "\n".join(DATA_TEMPLATE) + "\r"
  31 DATA_SPLIT = [x + "\n" for x in DATA_TEMPLATE]
  32
  33 class TestGenericUnivNewlines(unittest.TestCase):
  34     # use a class variable DATA to define the data to write to the file
  35     # and a class variable NEWLINE to set the expected newlines value
  36     READMODE = 'r'
  37     WRITEMODE = 'wb'
  38
  39     def setUp(self):
  40         data = self.DATA
  41         if "b" in self.WRITEMODE:
  42             data = data.encode("ascii")
  43         with self.open(support.TESTFN, self.WRITEMODE) as fp:
  44             fp.write(data)
  45
  46     def tearDown(self):
  47         try:
  48             os.unlink(support.TESTFN)
  49         except:
  50             pass
  51
  52     def test_read(self):
  53         with self.open(support.TESTFN, self.READMODE) as fp:
  54             data = fp.read()
  55         self.assertEqual(data, DATA_LF)
  56         self.assertEqual(repr(fp.newlines), repr(self.NEWLINE))
  57
  58     def test_readlines(self):
  59         with self.open(support.TESTFN, self.READMODE) as fp:
  60             data = fp.readlines()
  61         self.assertEqual(data, DATA_SPLIT)
  62         self.assertEqual(repr(fp.newlines), repr(self.NEWLINE))
  63
  64     def test_readline(self):
  65         with self.open(support.TESTFN, self.READMODE) as fp:
  66             data = []
  67             d = fp.readline()
  68             while d:
  69                 data.append(d)
  70                 d = fp.readline()
  71         self.assertEqual(data, DATA_SPLIT)
  72         self.assertEqual(repr(fp.newlines), repr(self.NEWLINE))
  73
  74     def test_seek(self):
  75         with self.open(support.TESTFN, self.READMODE) as fp:
  76             fp.readline()
  77             pos = fp.tell()
  78             data = fp.readlines()
  79             self.assertEqual(data, DATA_SPLIT[1:])
  80             fp.seek(pos)
  81             data = fp.readlines()
  82         self.assertEqual(data, DATA_SPLIT[1:])
  83
  84
  85 class TestCRNewlines(TestGenericUnivNewlines):
  86     NEWLINE = '\r'
  87     DATA = DATA_CR
  88
  89 class TestLFNewlines(TestGenericUnivNewlines):
  90     NEWLINE = '\n'
  91     DATA = DATA_LF
  92
  93 class TestCRLFNewlines(TestGenericUnivNewlines):
  94     NEWLINE = '\r\n'
  95     DATA = DATA_CRLF
  96
  97     def test_tell(self):
  98         with self.open(support.TESTFN, self.READMODE) as fp:
  99             self.assertEqual(repr(fp.newlines), repr(None))
 100             data = fp.readline()
 101             pos = fp.tell()
 102         self.assertEqual(repr(fp.newlines), repr(self.NEWLINE))
 103
 104 class TestMixedNewlines(TestGenericUnivNewlines):
 105     NEWLINE = ('\r', '\n')
 106     DATA = DATA_MIXED
 107
 108
 109 def test_main():
 110     base_tests = (TestCRNewlines,
 111                   TestLFNewlines,
 112                   TestCRLFNewlines,
 113                   TestMixedNewlines)
 114     tests = []
 115     # Test the C and Python implementations.
 116     for test in base_tests:
 117         class CTest(test):
 118             open = io.open
 119         CTest.__name__ = "C" + test.__name__
 120         class PyTest(test):
 121             open = staticmethod(pyio.open)
 122         PyTest.__name__ = "Py" + test.__name__
 123         tests.append(CTest)
 124         tests.append(PyTest)
 125     support.run_unittest(*tests)
 126
 127 if __name__ == '__main__':
 128     test_main()