Lib/test/test_univnewlines.py

# Tests universal newline support for both reading and parsing files.
import unittest
import test_support
import os
import sys

DATA_TEMPLATE=[
    "line1=1",
        "line2='this is a very long line designed to go past the magic " +
    "hundred character limit that is inside fileobject.c and which " +
    "is meant to speed up the common case, but we also want to test " +
    "the uncommon case, naturally.'",
    "def line3():pass"
    ]
DATA_LF = "\n".join(DATA_TEMPLATE) + "\n"
DATA_CR = "\r".join(DATA_TEMPLATE) + "\r"
DATA_CRLF = "\r\n".join(DATA_TEMPLATE) + "\r\n"
# Note that DATA_MIXED also tests the ability to recognize a lone \r
# before end-of-file.
DATA_MIXED = "\n".join(DATA_TEMPLATE) + "\r"
DATA_SPLIT = map(lambda x: x+"\n", DATA_TEMPLATE)

if not hasattr(sys.stdin, 'newlines'):
    raise test_support.TestSkipped, \
        "This Python does not have universal newline support"

class TestGenericUnivNewlines(unittest.TestCase):
    # use a class variable DATA to define the data to write to the file
    # and a class variable NEWLINE to set the expected newlines value
    READMODE = 'U'
    WRITEMODE = 'wb'

    def setUp(self):
        fp = open(test_support.TESTFN, self.WRITEMODE)
        fp.write(self.DATA)
        fp.close()

    def tearDown(self):
        try:
            os.unlink(test_support.TESTFN)
        except:
            pass

    def test_read(self):
        fp = open(test_support.TESTFN, self.READMODE)
        data = fp.read()
        self.assertEqual(data, DATA_LF)
        self.assertEqual(`fp.newlines`, `self.NEWLINE`)

    def test_readlines(self):
        fp = open(test_support.TESTFN, self.READMODE)
        data = fp.readlines()
        self.assertEqual(data, DATA_SPLIT)
        self.assertEqual(`fp.newlines`, `self.NEWLINE`)

    def test_readline(self):
        fp = open(test_support.TESTFN, self.READMODE)
        data = []
        d = fp.readline()
        while d:
            data.append(d)
            d = fp.readline()
        self.assertEqual(data, DATA_SPLIT)
        self.assertEqual(`fp.newlines`, `self.NEWLINE`)

    def test_seek(self):
        fp = open(test_support.TESTFN, self.READMODE)
        fp.readline()
        pos = fp.tell()
        data = fp.readlines()
        self.assertEqual(data, DATA_SPLIT[1:])
        fp.seek(pos)
        data = fp.readlines()
        self.assertEqual(data, DATA_SPLIT[1:])

    def test_execfile(self):
        dict = {}
        execfile(test_support.TESTFN, dict)
        func = dict['line3']
        self.assertEqual(func.func_code.co_firstlineno, 3)


class TestNativeNewlines(TestGenericUnivNewlines):
    NEWLINE=None
    DATA=DATA_LF
    READMODE='r'
    WRITEMODE='w'

class TestCRNewlines(TestGenericUnivNewlines):
    NEWLINE='\r'
    DATA=DATA_CR

class TestLFNewlines(TestGenericUnivNewlines):
    NEWLINE='\n'
    DATA=DATA_LF

class TestCRLFNewlines(TestGenericUnivNewlines):
    NEWLINE='\r\n'
    DATA=DATA_CRLF

class TestMixedNewlines(TestGenericUnivNewlines):
    NEWLINE=('\r', '\n')
    DATA=DATA_MIXED


def test_main():
    test_support.run_unittest(TestNativeNewlines)
    test_support.run_unittest(TestCRNewlines)
    test_support.run_unittest(TestLFNewlines)
    test_support.run_unittest(TestCRLFNewlines)
    test_support.run_unittest(TestMixedNewlines)

if __name__ == '__main__':
    test_main()