/External.LCA_RESTRICTED/Languages/IronPython/27/Lib/test/test_gzip.py

#! /usr/bin/env python

"""Test script for the gzip module.

"""



import unittest

from test import test_support

import os

import io

import struct

gzip = test_support.import_module('gzip')



data1 = """  int length=DEFAULTALLOC, err = Z_OK;

  PyObject *RetVal;

  int flushmode = Z_FINISH;

  unsigned long start_total_out;



"""



data2 = """/* zlibmodule.c -- gzip-compatible data compression */

/* See http://www.gzip.org/zlib/

/* See http://www.winimage.com/zLibDll for Windows */

"""





class TestGzip(unittest.TestCase):

    filename = test_support.TESTFN



    def setUp(self):

        test_support.unlink(self.filename)



    def tearDown(self):

        test_support.unlink(self.filename)





    def test_write(self):

        f = gzip.GzipFile(self.filename, 'wb') ; f.write(data1 * 50)



        # Try flush and fileno.

        f.flush()

        f.fileno()

        if hasattr(os, 'fsync'):

            os.fsync(f.fileno())

        f.close()



        # Test multiple close() calls.

        f.close()



    def test_read(self):

        self.test_write()

        # Try reading.

        f = gzip.GzipFile(self.filename, 'r') ; d = f.read() ; f.close()

        self.assertEqual(d, data1*50)



    def test_append(self):

        self.test_write()

        # Append to the previous file

        f = gzip.GzipFile(self.filename, 'ab') ; f.write(data2 * 15) ; f.close()



        f = gzip.GzipFile(self.filename, 'rb') ; d = f.read() ; f.close()

        self.assertEqual(d, (data1*50) + (data2*15))



    def test_many_append(self):

        # Bug #1074261 was triggered when reading a file that contained

        # many, many members.  Create such a file and verify that reading it

        # works.

        f = gzip.open(self.filename, 'wb', 9)

        f.write('a')

        f.close()

        for i in range(0,200):

            f = gzip.open(self.filename, "ab", 9) # append

            f.write('a')

            f.close()



        # Try reading the file

        zgfile = gzip.open(self.filename, "rb")

        contents = ""

        while 1:

            ztxt = zgfile.read(8192)

            contents += ztxt

            if not ztxt: break

        zgfile.close()

        self.assertEquals(contents, 'a'*201)



    def test_buffered_reader(self):

        # Issue #7471: a GzipFile can be wrapped in a BufferedReader for

        # performance.

        self.test_write()



        f = gzip.GzipFile(self.filename, 'rb')

        with io.BufferedReader(f) as r:

            lines = [line for line in r]



        self.assertEqual(lines, 50 * data1.splitlines(True))



    def test_readline(self):

        self.test_write()

        # Try .readline() with varying line lengths



        f = gzip.GzipFile(self.filename, 'rb')

        line_length = 0

        while 1:

            L = f.readline(line_length)

            if L == "" and line_length != 0: break

            self.assertTrue(len(L) <= line_length)

            line_length = (line_length + 1) % 50

        f.close()



    def test_readlines(self):

        self.test_write()

        # Try .readlines()



        f = gzip.GzipFile(self.filename, 'rb')

        L = f.readlines()

        f.close()



        f = gzip.GzipFile(self.filename, 'rb')

        while 1:

            L = f.readlines(150)

            if L == []: break

        f.close()



    def test_seek_read(self):

        self.test_write()

        # Try seek, read test



        f = gzip.GzipFile(self.filename)

        while 1:

            oldpos = f.tell()

            line1 = f.readline()

            if not line1: break

            newpos = f.tell()

            f.seek(oldpos)  # negative seek

            if len(line1)>10:

                amount = 10

            else:

                amount = len(line1)

            line2 = f.read(amount)

            self.assertEqual(line1[:amount], line2)

            f.seek(newpos)  # positive seek

        f.close()



    def test_seek_whence(self):

        self.test_write()

        # Try seek(whence=1), read test



        f = gzip.GzipFile(self.filename)

        f.read(10)

        f.seek(10, whence=1)

        y = f.read(10)

        f.close()

        self.assertEquals(y, data1[20:30])



    def test_seek_write(self):

        # Try seek, write test

        f = gzip.GzipFile(self.filename, 'w')

        for pos in range(0, 256, 16):

            f.seek(pos)

            f.write('GZ\n')

        f.close()



    def test_mode(self):

        self.test_write()

        f = gzip.GzipFile(self.filename, 'r')

        self.assertEqual(f.myfileobj.mode, 'rb')

        f.close()



    def test_1647484(self):

        for mode in ('wb', 'rb'):

            f = gzip.GzipFile(self.filename, mode)

            self.assertTrue(hasattr(f, "name"))

            self.assertEqual(f.name, self.filename)

            f.close()



    def test_mtime(self):

        mtime = 123456789

        fWrite = gzip.GzipFile(self.filename, 'w', mtime = mtime)

        fWrite.write(data1)

        fWrite.close()

        fRead = gzip.GzipFile(self.filename)

        dataRead = fRead.read()

        self.assertEqual(dataRead, data1)

        self.assertTrue(hasattr(fRead, 'mtime'))

        self.assertEqual(fRead.mtime, mtime)

        fRead.close()



    def test_metadata(self):

        mtime = 123456789



        fWrite = gzip.GzipFile(self.filename, 'w', mtime = mtime)

        fWrite.write(data1)

        fWrite.close()



        fRead = open(self.filename, 'rb')



        # see RFC 1952: http://www.faqs.org/rfcs/rfc1952.html



        idBytes = fRead.read(2)

        self.assertEqual(idBytes, '\x1f\x8b') # gzip ID



        cmByte = fRead.read(1)

        self.assertEqual(cmByte, '\x08') # deflate



        flagsByte = fRead.read(1)

        self.assertEqual(flagsByte, '\x08') # only the FNAME flag is set



        mtimeBytes = fRead.read(4)

        self.assertEqual(mtimeBytes, struct.pack('<i', mtime)) # little-endian



        xflByte = fRead.read(1)

        self.assertEqual(xflByte, '\x02') # maximum compression



        osByte = fRead.read(1)

        self.assertEqual(osByte, '\xff') # OS "unknown" (OS-independent)



        # Since the FNAME flag is set, the zero-terminated filename follows.

        # RFC 1952 specifies that this is the name of the input file, if any.

        # However, the gzip module defaults to storing the name of the output

        # file in this field.

        nameBytes = fRead.read(len(self.filename) + 1)

        self.assertEqual(nameBytes, self.filename + '\x00')



        # Since no other flags were set, the header ends here.

        # Rather than process the compressed data, let's seek to the trailer.

        fRead.seek(os.stat(self.filename).st_size - 8)



        crc32Bytes = fRead.read(4) # CRC32 of uncompressed data [data1]

        self.assertEqual(crc32Bytes, '\xaf\xd7d\x83')



        isizeBytes = fRead.read(4)

        self.assertEqual(isizeBytes, struct.pack('<i', len(data1)))



        fRead.close()



    def test_with_open(self):

        # GzipFile supports the context management protocol

        with gzip.GzipFile(self.filename, "wb") as f:

            f.write(b"xxx")

        f = gzip.GzipFile(self.filename, "rb")

        f.close()

        try:

            with f:

                pass

        except ValueError:

            pass

        else:

            self.fail("__enter__ on a closed file didn't raise an exception")

        try:

            with gzip.GzipFile(self.filename, "wb") as f:

                1 // 0

        except ZeroDivisionError:

            pass

        else:

            self.fail("1 // 0 didn't raise an exception")



    def test_zero_padded_file(self):

        with gzip.GzipFile(self.filename, "wb") as f:

            f.write(data1 * 50)



        # Pad the file with zeroes

        with open(self.filename, "ab") as f:

            f.write("\x00" * 50)



        with gzip.GzipFile(self.filename, "rb") as f:

            d = f.read()

            self.assertEqual(d, data1 * 50, "Incorrect data in file")



def test_main(verbose=None):

    test_support.run_unittest(TestGzip)



if __name__ == "__main__":

    test_main(verbose=True)