[Python-checkins] cpython (merge default -> default): Merge heads
nadeem.vawda
python-checkins at python.org
Fri May 27 02:02:59 CEST 2011
http://hg.python.org/cpython/rev/170fad802bb9
changeset: 70433:170fad802bb9
parent: 70430:3555cf6f9c98
parent: 70432:0be55601f948
user: Nadeem Vawda <nadeem.vawda at gmail.com>
date: Fri May 27 02:03:06 2011 +0200
summary:
Merge heads
files:
Doc/library/bz2.rst | 39 +++++++-
Lib/bz2.py | 47 ++++++++---
Lib/test/test_bz2.py | 126 ++++++++++++++++++++++++++++++-
Misc/NEWS | 3 +
4 files changed, 192 insertions(+), 23 deletions(-)
diff --git a/Doc/library/bz2.rst b/Doc/library/bz2.rst
--- a/Doc/library/bz2.rst
+++ b/Doc/library/bz2.rst
@@ -37,14 +37,18 @@
*fileobj*), or operate directly on a named file (named by *filename*).
Exactly one of these two parameters should be provided.
- The *mode* argument can be either ``'r'`` for reading (default), or ``'w'``
- for writing.
+ The *mode* argument can be either ``'r'`` for reading (default), ``'w'`` for
+ overwriting, or ``'a'`` for appending. If *fileobj* is provided, a mode of
+ ``'w'`` does not truncate the file, and is instead equivalent to ``'a'``.
The *buffering* argument is ignored. Its use is deprecated.
- If *mode* is ``'w'``, *compresslevel* can be a number between ``1`` and
- ``9`` specifying the level of compression: ``1`` produces the least
- compression, and ``9`` (default) produces the most compression.
+ If *mode* is ``'w'`` or ``'a'``, *compresslevel* can be a number between
+ ``1`` and ``9`` specifying the level of compression: ``1`` produces the
+ least compression, and ``9`` (default) produces the most compression.
+
+ If *mode* is ``'r'``, the input file may be the concatenation of multiple
+ compressed streams.
:class:`BZ2File` provides all of the members specified by the
:class:`io.BufferedIOBase`, except for :meth:`detach` and :meth:`truncate`.
@@ -70,6 +74,10 @@
.. versionchanged:: 3.3
The *fileobj* argument to the constructor was added.
+ .. versionchanged:: 3.3
+ The ``'a'`` (append) mode was added, along with support for reading
+ multi-stream files.
+
Incremental (de)compression
---------------------------
@@ -106,14 +114,20 @@
incrementally. For one-shot compression, use the :func:`decompress` function
instead.
+ .. note::
+ This class does not transparently handle inputs containing multiple
+ compressed streams, unlike :func:`decompress` and :class:`BZ2File`. If
+ you need to decompress a multi-stream input with :class:`BZ2Decompressor`,
+ you must use a new decompressor for each stream.
+
.. method:: decompress(data)
Provide data to the decompressor object. Returns a chunk of decompressed
data if possible, or an empty byte string otherwise.
- Attempting to decompress data after the end of stream is reached raises
- an :exc:`EOFError`. If any data is found after the end of the stream, it
- is ignored and saved in the :attr:`unused_data` attribute.
+ Attempting to decompress data after the end of the current stream is
+ reached raises an :exc:`EOFError`. If any data is found after the end of
+ the stream, it is ignored and saved in the :attr:`unused_data` attribute.
.. attribute:: eof
@@ -127,6 +141,9 @@
Data found after the end of the compressed stream.
+ If this attribute is accessed before the end of the stream has been
+ reached, its value will be ``b''``.
+
One-shot (de)compression
------------------------
@@ -145,5 +162,11 @@
Decompress *data*.
+ If *data* is the concatenation of multiple compressed streams, decompress
+ all of the streams.
+
For incremental decompression, use a :class:`BZ2Decompressor` instead.
+ .. versionchanged:: 3.3
+ Support for multi-stream inputs was added.
+
diff --git a/Lib/bz2.py b/Lib/bz2.py
--- a/Lib/bz2.py
+++ b/Lib/bz2.py
@@ -76,6 +76,10 @@
mode = "wb"
mode_code = _MODE_WRITE
self._compressor = BZ2Compressor()
+ elif mode in ("a", "ab"):
+ mode = "ab"
+ mode_code = _MODE_WRITE
+ self._compressor = BZ2Compressor()
else:
raise ValueError("Invalid mode: {!r}".format(mode))
@@ -161,14 +165,25 @@
def _fill_buffer(self):
if self._buffer:
return True
+
+ if self._decompressor.unused_data:
+ rawblock = self._decompressor.unused_data
+ else:
+ rawblock = self._fp.read(_BUFFER_SIZE)
+
+ if not rawblock:
+ if self._decompressor.eof:
+ self._mode = _MODE_READ_EOF
+ self._size = self._pos
+ return False
+ else:
+ raise EOFError("Compressed file ended before the "
+ "end-of-stream marker was reached")
+
+ # Continue to next stream.
if self._decompressor.eof:
- self._mode = _MODE_READ_EOF
- self._size = self._pos
- return False
- rawblock = self._fp.read(_BUFFER_SIZE)
- if not rawblock:
- raise EOFError("Compressed file ended before the "
- "end-of-stream marker was reached")
+ self._decompressor = BZ2Decompressor()
+
self._buffer = self._decompressor.decompress(rawblock)
return True
@@ -384,9 +399,15 @@
"""
if len(data) == 0:
return b""
- decomp = BZ2Decompressor()
- result = decomp.decompress(data)
- if not decomp.eof:
- raise ValueError("Compressed data ended before the "
- "end-of-stream marker was reached")
- return result
+
+ result = b""
+ while True:
+ decomp = BZ2Decompressor()
+ result += decomp.decompress(data)
+ if not decomp.eof:
+ raise ValueError("Compressed data ended before the "
+ "end-of-stream marker was reached")
+ if not decomp.unused_data:
+ return result
+ # There is unused data left over. Proceed to next stream.
+ data = decomp.unused_data
diff --git a/Lib/test/test_bz2.py b/Lib/test/test_bz2.py
--- a/Lib/test/test_bz2.py
+++ b/Lib/test/test_bz2.py
@@ -84,9 +84,9 @@
else:
return self.DATA
- def createTempFile(self, crlf=False):
+ def createTempFile(self, crlf=False, streams=1):
with open(self.filename, "wb") as f:
- f.write(self.getData(crlf))
+ f.write(self.getData(crlf) * streams)
def testRead(self):
# "Test BZ2File.read()"
@@ -95,6 +95,26 @@
self.assertRaises(TypeError, bz2f.read, None)
self.assertEqual(bz2f.read(), self.TEXT)
+ def testReadMultiStream(self):
+ # "Test BZ2File.read() with a multi stream archive"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ self.assertRaises(TypeError, bz2f.read, None)
+ self.assertEqual(bz2f.read(), self.TEXT * 5)
+
+ def testReadMonkeyMultiStream(self):
+ # "Test BZ2File.read() with a multi stream archive in which stream"
+ # "end is alined with internal buffer size"
+ buffer_size = bz2._BUFFER_SIZE
+ bz2._BUFFER_SIZE = len(self.DATA)
+ try:
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ self.assertRaises(TypeError, bz2f.read, None)
+ self.assertEqual(bz2f.read(), self.TEXT * 5)
+ finally:
+ bz2._BUFFER_SIZE = buffer_size
+
def testRead0(self):
# "Test BBZ2File.read(0)"
self.createTempFile()
@@ -114,6 +134,18 @@
text += str
self.assertEqual(text, self.TEXT)
+ def testReadChunk10MultiStream(self):
+ # "Test BZ2File.read() in chunks of 10 bytes with a multi stream archive"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ text = b''
+ while 1:
+ str = bz2f.read(10)
+ if not str:
+ break
+ text += str
+ self.assertEqual(text, self.TEXT * 5)
+
def testRead100(self):
# "Test BZ2File.read(100)"
self.createTempFile()
@@ -151,6 +183,15 @@
for line in sio.readlines():
self.assertEqual(bz2f.readline(), line)
+ def testReadLineMultiStream(self):
+ # "Test BZ2File.readline() with a multi stream archive"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ self.assertRaises(TypeError, bz2f.readline, None)
+ sio = BytesIO(self.TEXT * 5)
+ for line in sio.readlines():
+ self.assertEqual(bz2f.readline(), line)
+
def testReadLines(self):
# "Test BZ2File.readlines()"
self.createTempFile()
@@ -159,6 +200,14 @@
sio = BytesIO(self.TEXT)
self.assertEqual(bz2f.readlines(), sio.readlines())
+ def testReadLinesMultiStream(self):
+ # "Test BZ2File.readlines() with a multi stream archive"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ self.assertRaises(TypeError, bz2f.readlines, None)
+ sio = BytesIO(self.TEXT * 5)
+ self.assertEqual(bz2f.readlines(), sio.readlines())
+
def testIterator(self):
# "Test iter(BZ2File)"
self.createTempFile()
@@ -166,6 +215,13 @@
sio = BytesIO(self.TEXT)
self.assertEqual(list(iter(bz2f)), sio.readlines())
+ def testIteratorMultiStream(self):
+ # "Test iter(BZ2File) with a multi stream archive"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ sio = BytesIO(self.TEXT * 5)
+ self.assertEqual(list(iter(bz2f)), sio.readlines())
+
def testClosedIteratorDeadlock(self):
# "Test that iteration on a closed bz2file releases the lock."
# http://bugs.python.org/issue3309
@@ -217,6 +273,17 @@
self.assertRaises(IOError, bz2f.write, b"a")
self.assertRaises(IOError, bz2f.writelines, [b"a"])
+ def testAppend(self):
+ # "Test BZ2File.write()"
+ with BZ2File(self.filename, "w") as bz2f:
+ self.assertRaises(TypeError, bz2f.write)
+ bz2f.write(self.TEXT)
+ with BZ2File(self.filename, "a") as bz2f:
+ self.assertRaises(TypeError, bz2f.write)
+ bz2f.write(self.TEXT)
+ with open(self.filename, 'rb') as f:
+ self.assertEqual(self.decompress(f.read()), self.TEXT * 2)
+
def testSeekForward(self):
# "Test BZ2File.seek(150, 0)"
self.createTempFile()
@@ -225,6 +292,14 @@
bz2f.seek(150)
self.assertEqual(bz2f.read(), self.TEXT[150:])
+ def testSeekForwardMultiStream(self):
+ # "Test BZ2File.seek(150, 0) across stream boundaries"
+ self.createTempFile(streams=2)
+ with BZ2File(self.filename) as bz2f:
+ self.assertRaises(TypeError, bz2f.seek)
+ bz2f.seek(len(self.TEXT) + 150)
+ self.assertEqual(bz2f.read(), self.TEXT[150:])
+
def testSeekBackwards(self):
# "Test BZ2File.seek(-150, 1)"
self.createTempFile()
@@ -233,6 +308,16 @@
bz2f.seek(-150, 1)
self.assertEqual(bz2f.read(), self.TEXT[500-150:])
+ def testSeekBackwardsMultiStream(self):
+ # "Test BZ2File.seek(-150, 1) across stream boundaries"
+ self.createTempFile(streams=2)
+ with BZ2File(self.filename) as bz2f:
+ readto = len(self.TEXT) + 100
+ while readto > 0:
+ readto -= len(bz2f.read(readto))
+ bz2f.seek(-150, 1)
+ self.assertEqual(bz2f.read(), self.TEXT[100-150:] + self.TEXT)
+
def testSeekBackwardsFromEnd(self):
# "Test BZ2File.seek(-150, 2)"
self.createTempFile()
@@ -240,6 +325,13 @@
bz2f.seek(-150, 2)
self.assertEqual(bz2f.read(), self.TEXT[len(self.TEXT)-150:])
+ def testSeekBackwardsFromEndMultiStream(self):
+ # "Test BZ2File.seek(-1000, 2) across stream boundaries"
+ self.createTempFile(streams=2)
+ with BZ2File(self.filename) as bz2f:
+ bz2f.seek(-1000, 2)
+ self.assertEqual(bz2f.read(), (self.TEXT * 2)[-1000:])
+
def testSeekPostEnd(self):
# "Test BZ2File.seek(150000)"
self.createTempFile()
@@ -248,6 +340,14 @@
self.assertEqual(bz2f.tell(), len(self.TEXT))
self.assertEqual(bz2f.read(), b"")
+ def testSeekPostEndMultiStream(self):
+ # "Test BZ2File.seek(150000)"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ bz2f.seek(150000)
+ self.assertEqual(bz2f.tell(), len(self.TEXT) * 5)
+ self.assertEqual(bz2f.read(), b"")
+
def testSeekPostEndTwice(self):
# "Test BZ2File.seek(150000) twice"
self.createTempFile()
@@ -257,6 +357,15 @@
self.assertEqual(bz2f.tell(), len(self.TEXT))
self.assertEqual(bz2f.read(), b"")
+ def testSeekPostEndTwiceMultiStream(self):
+ # "Test BZ2File.seek(150000) twice with a multi stream archive"
+ self.createTempFile(streams=5)
+ with BZ2File(self.filename) as bz2f:
+ bz2f.seek(150000)
+ bz2f.seek(150000)
+ self.assertEqual(bz2f.tell(), len(self.TEXT) * 5)
+ self.assertEqual(bz2f.read(), b"")
+
def testSeekPreStart(self):
# "Test BZ2File.seek(-150, 0)"
self.createTempFile()
@@ -265,6 +374,14 @@
self.assertEqual(bz2f.tell(), 0)
self.assertEqual(bz2f.read(), self.TEXT)
+ def testSeekPreStartMultiStream(self):
+ # "Test BZ2File.seek(-150, 0) with a multi stream archive"
+ self.createTempFile(streams=2)
+ with BZ2File(self.filename) as bz2f:
+ bz2f.seek(-150)
+ self.assertEqual(bz2f.tell(), 0)
+ self.assertEqual(bz2f.read(), self.TEXT * 2)
+
def testFileno(self):
# "Test BZ2File.fileno()"
self.createTempFile()
@@ -510,6 +627,11 @@
# "Test decompress() function with incomplete data"
self.assertRaises(ValueError, bz2.decompress, self.DATA[:-10])
+ def testDecompressMultiStream(self):
+ # "Test decompress() function for data with multiple streams"
+ text = bz2.decompress(self.DATA * 5)
+ self.assertEqual(text, self.TEXT * 5)
+
def test_main():
support.run_unittest(
BZ2FileTest,
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -161,6 +161,9 @@
Library
-------
+- Issue #1625: BZ2File and bz2.decompress() now support multi-stream files.
+ Initial patch by Nir Aides.
+
- Issue #8796: codecs.open() calls the builtin open() function instead of using
StreamReaderWriter. Deprecate StreamReader, StreamWriter, StreamReaderWriter,
StreamRecoder and EncodedFile() of the codec module. Use the builtin open()
--
Repository URL: http://hg.python.org/cpython
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