(mostly stuff specified by PEP 302). There are two ABCs, PyLoader and
PyPycLoader, which help with implementing source and source/bytecode loaders by
implementing load_module in terms of other methods. This removes a lot of
gritty details loaders typically have to worry about.
The main io module now uses the C implementation. The Python one still exists
in Lib/_pyio.py for ease of testing new features and usefulness to other
implementers.
The rewrite was done by Antoine Pitrou and Amaury Forgeot d'Arc. I was slightly
helpful at the end. :)
Following are the log messages from the io-c branch:
Merged revisions 68683-68685,68687-68689,68693,68704,68741-68743,68745,68747,68752-68754,68756,68758,68812,68816-68817,68820-68822,68824-68825,68828,68876-68877,69037,69044,69104,69115,69194,69626-69629,69636,69638,69641-69642,69644-69654,69656-69661,69671,69677,69812-69815,69817,69827-69830,69839,69841-69845,69848,69850,69852,69854,69860,69865-69866,69868,69872-69873,69885,69888,69891-69893,69911,69913-69916,69963,70033,70035,70038,70041-70048,70067-70070,70075,70112,70133,70135,70140 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/io-c
........
r68683 | antoine.pitrou | 2009-01-17 17:13:48 -0600 (Sat, 17 Jan 2009) | 3 lines
Merge in changes from the io-c sandbox. Tests will follow in separate commits.
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r68684 | antoine.pitrou | 2009-01-17 17:17:26 -0600 (Sat, 17 Jan 2009) | 3 lines
Fixes and additions to test_io.py
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r68685 | antoine.pitrou | 2009-01-17 17:22:04 -0600 (Sat, 17 Jan 2009) | 1 line
Fix test_fileio
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r68687 | antoine.pitrou | 2009-01-17 17:35:11 -0600 (Sat, 17 Jan 2009) | 3 lines
Add dependency to _iomodule.h for the various C sources
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r68688 | antoine.pitrou | 2009-01-17 17:38:18 -0600 (Sat, 17 Jan 2009) | 3 lines
These precautions are not needed anymore!
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r68689 | antoine.pitrou | 2009-01-17 17:41:48 -0600 (Sat, 17 Jan 2009) | 3 lines
Fix another test
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r68693 | antoine.pitrou | 2009-01-17 17:49:58 -0600 (Sat, 17 Jan 2009) | 3 lines
Fix test_uu (which was using private attributes of TextIOWrapper)
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r68704 | antoine.pitrou | 2009-01-17 18:45:29 -0600 (Sat, 17 Jan 2009) | 3 lines
Most io sources are Py_ssize_t-clean (I don't know about bytesio and stringio)
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r68741 | antoine.pitrou | 2009-01-18 15:20:30 -0600 (Sun, 18 Jan 2009) | 3 lines
Check return type in TextIOWrapper.__next__
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r68742 | antoine.pitrou | 2009-01-18 15:28:48 -0600 (Sun, 18 Jan 2009) | 4 lines
Make binary buffered readline and iteration much faster
(8x as fast as the IOBase generic implementation)
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r68743 | antoine.pitrou | 2009-01-18 15:47:47 -0600 (Sun, 18 Jan 2009) | 3 lines
Reinsert test_io_after_close (was removed by mistake)
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r68745 | antoine.pitrou | 2009-01-18 16:16:06 -0600 (Sun, 18 Jan 2009) | 3 lines
Add read, read1 and write methods to BufferedIOBase
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r68747 | antoine.pitrou | 2009-01-18 16:35:58 -0600 (Sun, 18 Jan 2009) | 3 lines
Kill test failure
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r68752 | amaury.forgeotdarc | 2009-01-18 17:05:43 -0600 (Sun, 18 Jan 2009) | 3 lines
Fix a segfault when e.g a BufferedReader is created with a FileIO in
read mode.
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r68753 | antoine.pitrou | 2009-01-18 17:13:09 -0600 (Sun, 18 Jan 2009) | 3 lines
Add truncate() to text IO objects
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r68754 | antoine.pitrou | 2009-01-18 17:51:08 -0600 (Sun, 18 Jan 2009) | 3 lines
Remove IOBase.__del__ and replace it with custom code with tp_dealloc
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r68756 | antoine.pitrou | 2009-01-18 18:10:16 -0600 (Sun, 18 Jan 2009) | 3 lines
Remove irrelevant comment.
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r68758 | antoine.pitrou | 2009-01-18 18:36:16 -0600 (Sun, 18 Jan 2009) | 3 lines
in importlib:_fileio._FileIO -> _io.FileIO
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r68812 | antoine.pitrou | 2009-01-20 14:15:51 -0600 (Tue, 20 Jan 2009) | 3 lines
Add garbage collection support to FileIO objects
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r68816 | antoine.pitrou | 2009-01-20 14:56:28 -0600 (Tue, 20 Jan 2009) | 3 lines
Add GC support to Buffered and Text IO objects
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r68817 | antoine.pitrou | 2009-01-20 15:19:45 -0600 (Tue, 20 Jan 2009) | 3 lines
Add some file headers
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r68820 | antoine.pitrou | 2009-01-20 15:29:59 -0600 (Tue, 20 Jan 2009) | 3 lines
Add class TextIOBase
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r68821 | antoine.pitrou | 2009-01-20 15:36:16 -0600 (Tue, 20 Jan 2009) | 3 lines
Add properties to TextIOBase
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r68822 | antoine.pitrou | 2009-01-20 15:41:19 -0600 (Tue, 20 Jan 2009) | 3 lines
Disable the pure Python TextIOBase class, and inject C the implementation instead
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r68824 | antoine.pitrou | 2009-01-20 16:36:28 -0600 (Tue, 20 Jan 2009) | 3 lines
Fix two leaks
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r68825 | antoine.pitrou | 2009-01-20 16:38:29 -0600 (Tue, 20 Jan 2009) | 3 lines
FileIO.name is just a plain attribute, we can set it directly
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r68828 | antoine.pitrou | 2009-01-20 17:06:33 -0600 (Tue, 20 Jan 2009) | 3 lines
Speed up closed checks on text IO objects. Good for a 25% speedup on small ops.
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r68876 | antoine.pitrou | 2009-01-23 17:01:25 -0600 (Fri, 23 Jan 2009) | 3 lines
Two typos
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r68877 | antoine.pitrou | 2009-01-23 18:13:20 -0600 (Fri, 23 Jan 2009) | 3 lines
Remove two unused functions
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r69037 | amaury.forgeotdarc | 2009-01-27 17:10:25 -0600 (Tue, 27 Jan 2009) | 2 lines
Update the win32 project files
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r69044 | antoine.pitrou | 2009-01-27 18:51:07 -0600 (Tue, 27 Jan 2009) | 3 lines
Improve heuristic in IncrementalNewlineDecoder + some micro-optimizations
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r69104 | antoine.pitrou | 2009-01-29 15:23:42 -0600 (Thu, 29 Jan 2009) | 3 lines
Fix some crashers found by Victor
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r69115 | hirokazu.yamamoto | 2009-01-29 20:36:28 -0600 (Thu, 29 Jan 2009) | 1 line
Updated VC6 project file.
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r69194 | antoine.pitrou | 2009-02-01 16:57:18 -0600 (Sun, 01 Feb 2009) | 3 lines
Fix downcasting warnings in 32-bit mode with 64-bit offsets (Windows)
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r69626 | benjamin.peterson | 2009-02-14 17:33:34 -0600 (Sat, 14 Feb 2009) | 1 line
only catch AttributeError and UnsupportedOperation
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r69627 | benjamin.peterson | 2009-02-14 21:35:28 -0600 (Sat, 14 Feb 2009) | 1 line
give the IO module its own state and store the os and locale modules in it
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r69628 | benjamin.peterson | 2009-02-14 22:08:32 -0600 (Sat, 14 Feb 2009) | 1 line
put interned strings in the module state structure
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r69629 | benjamin.peterson | 2009-02-14 22:15:29 -0600 (Sat, 14 Feb 2009) | 1 line
put UnsupportedOperation in the module state
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r69636 | benjamin.peterson | 2009-02-15 08:31:42 -0600 (Sun, 15 Feb 2009) | 1 line
dealloc unsupported_operation
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r69638 | benjamin.peterson | 2009-02-15 09:24:45 -0600 (Sun, 15 Feb 2009) | 1 line
actually test the C implementation
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r69641 | benjamin.peterson | 2009-02-15 10:12:37 -0600 (Sun, 15 Feb 2009) | 5 lines
make interned strings globals again ;(
putting them in the module state was asking for trouble when the module
was dealloced before the classes in it were
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r69642 | benjamin.peterson | 2009-02-15 10:19:45 -0600 (Sun, 15 Feb 2009) | 1 line
actually test the python implementations
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r69644 | antoine.pitrou | 2009-02-15 11:59:30 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix memory leak in destructor when a Python class inherits from IOBase (or an IOBase-derived type)
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r69645 | antoine.pitrou | 2009-02-15 12:23:26 -0600 (Sun, 15 Feb 2009) | 3 lines
Add a warning about the embarassing state of IOBase finalization
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r69646 | antoine.pitrou | 2009-02-15 13:14:42 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix opening of 8-bit filenames with FileIO
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r69647 | antoine.pitrou | 2009-02-15 13:20:22 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix leak in FileIO constructor
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r69648 | antoine.pitrou | 2009-02-15 13:58:16 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix some refleaks
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r69649 | antoine.pitrou | 2009-02-15 14:05:13 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix a leak in IOBase.writelines
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r69650 | antoine.pitrou | 2009-02-15 14:11:56 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix memory leak in BufferedWriter.truncate
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r69651 | antoine.pitrou | 2009-02-15 14:25:34 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix a leak in TextIOWrapper.seek
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r69652 | antoine.pitrou | 2009-02-15 14:26:28 -0600 (Sun, 15 Feb 2009) | 3 lines
Unify implementations of truncate for buffered objects
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r69653 | antoine.pitrou | 2009-02-15 15:15:15 -0600 (Sun, 15 Feb 2009) | 3 lines
Fix more leaks in TextIOWrapper
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r69654 | antoine.pitrou | 2009-02-15 15:21:57 -0600 (Sun, 15 Feb 2009) | 3 lines
Smaller chunk size for a faster test
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r69656 | benjamin.peterson | 2009-02-15 17:29:48 -0600 (Sun, 15 Feb 2009) | 1 line
braces make this much clearer
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r69657 | benjamin.peterson | 2009-02-15 17:46:07 -0600 (Sun, 15 Feb 2009) | 1 line
use the correct macro
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r69658 | antoine.pitrou | 2009-02-15 19:38:59 -0600 (Sun, 15 Feb 2009) | 5 lines
Fix crash in test_urllib2_localnet in debug mode. It was due to an HTTPResponse
object being revived when calling its close() method in IOBase's tp_dealloc.
_PyIOBase_finalize() starts looking scary...
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r69659 | benjamin.peterson | 2009-02-15 20:55:48 -0600 (Sun, 15 Feb 2009) | 1 line
fix segfault on initialization failing
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r69660 | benjamin.peterson | 2009-02-15 21:09:31 -0600 (Sun, 15 Feb 2009) | 1 line
apparently locale.getprefferedencoding() can raise a ImportError, too
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r69661 | benjamin.peterson | 2009-02-15 21:54:15 -0600 (Sun, 15 Feb 2009) | 1 line
it's amazing this worked at all; I was using the wrong structs!
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r69671 | benjamin.peterson | 2009-02-16 08:38:27 -0600 (Mon, 16 Feb 2009) | 1 line
add garbage collection support to bytesio
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r69677 | benjamin.peterson | 2009-02-16 10:31:03 -0600 (Mon, 16 Feb 2009) | 5 lines
reduce ImportError catching code duplication
I'm not sure this makes the code clearer with its new gotos, but
at least I added a big fat comment
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r69812 | antoine.pitrou | 2009-02-20 13:50:16 -0600 (Fri, 20 Feb 2009) | 3 lines
_StringIO now belongs to the _io modules, rather to its own _stringio module
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r69813 | antoine.pitrou | 2009-02-20 13:58:22 -0600 (Fri, 20 Feb 2009) | 3 lines
Add a test for StringIO properties
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r69814 | antoine.pitrou | 2009-02-20 14:06:03 -0600 (Fri, 20 Feb 2009) | 3 lines
Reimplement a few trivial StringIO functions and properties in C
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r69815 | antoine.pitrou | 2009-02-20 14:13:11 -0600 (Fri, 20 Feb 2009) | 3 lines
Add the line_buffering property to TextIOWrapper, and test for it
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r69817 | antoine.pitrou | 2009-02-20 14:45:50 -0600 (Fri, 20 Feb 2009) | 4 lines
Allow IncrementalNewlineDecoder to take unicode objects as decoding input if the decoder parameter is None
This will help rewriting StringIO to C
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r69827 | antoine.pitrou | 2009-02-20 19:00:30 -0600 (Fri, 20 Feb 2009) | 3 lines
Rewrite most of StringIO in C. Some almost empty stubs remain to be converted.
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r69828 | antoine.pitrou | 2009-02-20 19:09:25 -0600 (Fri, 20 Feb 2009) | 3 lines
Plug a leak, and remove an unused string
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r69829 | benjamin.peterson | 2009-02-20 20:02:28 -0600 (Fri, 20 Feb 2009) | 1 line
this assertions makes more sense here
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r69830 | benjamin.peterson | 2009-02-20 20:03:04 -0600 (Fri, 20 Feb 2009) | 1 line
PyModule_AddObject can fail; simplify this code with a macro
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r69839 | antoine.pitrou | 2009-02-21 12:54:01 -0600 (Sat, 21 Feb 2009) | 3 lines
StringIO is now written entirely in C (and blazingly fast)
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r69841 | benjamin.peterson | 2009-02-21 14:05:40 -0600 (Sat, 21 Feb 2009) | 1 line
split the Python implementation of io into another module and rewrite the tests to test both implementations
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r69842 | benjamin.peterson | 2009-02-21 14:10:00 -0600 (Sat, 21 Feb 2009) | 1 line
closed is not a function
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r69843 | benjamin.peterson | 2009-02-21 14:13:04 -0600 (Sat, 21 Feb 2009) | 1 line
fix __all__ test
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r69844 | benjamin.peterson | 2009-02-21 14:21:24 -0600 (Sat, 21 Feb 2009) | 1 line
fix the rest of the Misc tests
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r69845 | benjamin.peterson | 2009-02-21 14:26:59 -0600 (Sat, 21 Feb 2009) | 1 line
RawIOBase is better for FileIO
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r69848 | benjamin.peterson | 2009-02-21 15:33:53 -0600 (Sat, 21 Feb 2009) | 1 line
fix some more tests broken by bag argument validation
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r69850 | benjamin.peterson | 2009-02-21 16:16:42 -0600 (Sat, 21 Feb 2009) | 1 line
make the python IncrementalNewineDecoder support a None decoder
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r69852 | benjamin.peterson | 2009-02-21 16:36:09 -0600 (Sat, 21 Feb 2009) | 1 line
fix a BlockingIOError.characters_written bug
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r69854 | benjamin.peterson | 2009-02-21 16:49:02 -0600 (Sat, 21 Feb 2009) | 1 line
check whence
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r69860 | benjamin.peterson | 2009-02-21 17:42:50 -0600 (Sat, 21 Feb 2009) | 1 line
fix some of these Misbehaving io tests
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r69865 | benjamin.peterson | 2009-02-21 18:59:52 -0600 (Sat, 21 Feb 2009) | 1 line
don't use super here()
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r69866 | benjamin.peterson | 2009-02-21 19:05:28 -0600 (Sat, 21 Feb 2009) | 1 line
use implementation specific classes
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r69868 | benjamin.peterson | 2009-02-21 22:12:05 -0600 (Sat, 21 Feb 2009) | 1 line
use a more DRY friendly approach to injecting module contents into test classes
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r69872 | antoine.pitrou | 2009-02-22 13:39:45 -0600 (Sun, 22 Feb 2009) | 3 lines
Sanitize destructor behaviour of IOBase. Now Python-defined attributes can be accessed from close().
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r69873 | antoine.pitrou | 2009-02-22 13:50:14 -0600 (Sun, 22 Feb 2009) | 4 lines
Only set the internal fd after it has been checked to be valid
(otherwise, the destructor will attempt to close it)
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r69885 | benjamin.peterson | 2009-02-22 15:30:14 -0600 (Sun, 22 Feb 2009) | 1 line
convert some other tests to use both io implementations
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r69888 | antoine.pitrou | 2009-02-22 17:03:16 -0600 (Sun, 22 Feb 2009) | 3 lines
Silence all exceptions when finalizing
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r69891 | benjamin.peterson | 2009-02-22 17:27:24 -0600 (Sun, 22 Feb 2009) | 1 line
convert another test to test both io implementations
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r69892 | benjamin.peterson | 2009-02-22 17:32:15 -0600 (Sun, 22 Feb 2009) | 1 line
help poor people like me to find their io tests (did I miss any?)
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r69893 | benjamin.peterson | 2009-02-22 17:37:56 -0600 (Sun, 22 Feb 2009) | 1 line
put a big note in the test telling people to write tests for both implementations now
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r69911 | antoine.pitrou | 2009-02-23 13:57:18 -0600 (Mon, 23 Feb 2009) | 3 lines
expose DEFAULT_BUFFER_SIZE again (fixes a bunch of test failures)
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r69913 | antoine.pitrou | 2009-02-23 14:10:30 -0600 (Mon, 23 Feb 2009) | 4 lines
Do the cyclic garbage collection tests only on the C version.
The Python version is helpless as it uses __del__.
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r69914 | antoine.pitrou | 2009-02-23 14:21:41 -0600 (Mon, 23 Feb 2009) | 3 lines
Adapt test_largefile to test both implementations
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r69915 | antoine.pitrou | 2009-02-23 14:25:14 -0600 (Mon, 23 Feb 2009) | 3 lines
One small failure
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r69916 | antoine.pitrou | 2009-02-23 14:28:33 -0600 (Mon, 23 Feb 2009) | 3 lines
Add a comment, at BP's request
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r69963 | antoine.pitrou | 2009-02-25 09:42:59 -0600 (Wed, 25 Feb 2009) | 3 lines
Add a test of ABC inheritance
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r70033 | antoine.pitrou | 2009-02-27 15:49:50 -0600 (Fri, 27 Feb 2009) | 3 lines
The base classes now are ABCs.
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r70035 | benjamin.peterson | 2009-02-27 15:57:41 -0600 (Fri, 27 Feb 2009) | 1 line
good house keeping
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r70038 | antoine.pitrou | 2009-02-27 17:05:23 -0600 (Fri, 27 Feb 2009) | 4 lines
Make the buffer allocation overflow tests specific to the C implementation, since the Python implementation resizes its buffers when needed rather than allocating them up front.
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r70041 | benjamin.peterson | 2009-02-27 18:26:12 -0600 (Fri, 27 Feb 2009) | 1 line
kill java naming for sanity
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r70042 | benjamin.peterson | 2009-02-27 18:28:53 -0600 (Fri, 27 Feb 2009) | 2 lines
timingTest is superseded by iobench
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r70043 | antoine.pitrou | 2009-02-27 19:13:50 -0600 (Fri, 27 Feb 2009) | 3 lines
Remove the last traces of java naming in test_io
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r70044 | antoine.pitrou | 2009-02-27 19:18:34 -0600 (Fri, 27 Feb 2009) | 3 lines
Better resource cleanup
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r70045 | antoine.pitrou | 2009-02-27 19:29:00 -0600 (Fri, 27 Feb 2009) | 3 lines
Remove dubious uses of super(), and fix one test
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r70046 | antoine.pitrou | 2009-02-27 19:31:00 -0600 (Fri, 27 Feb 2009) | 3 lines
Bump up CHUNK_SIZE (no need to make the Python version look slower than it is)
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r70047 | benjamin.peterson | 2009-02-27 20:03:26 -0600 (Fri, 27 Feb 2009) | 1 line
fix typo
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r70048 | benjamin.peterson | 2009-02-27 21:35:11 -0600 (Fri, 27 Feb 2009) | 1 line
move code to a better place
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r70067 | benjamin.peterson | 2009-02-28 10:43:20 -0600 (Sat, 28 Feb 2009) | 4 lines
1. make sure to undo buffered read aheads in BufferedRandom.seek()
2. refill the buffer if have <= 0
3. fix the last failing test_io test!
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r70068 | benjamin.peterson | 2009-02-28 10:57:50 -0600 (Sat, 28 Feb 2009) | 1 line
define read1() on the python implementation's BufferedIOBase
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r70069 | benjamin.peterson | 2009-02-28 11:01:17 -0600 (Sat, 28 Feb 2009) | 1 line
document read1() in BufferedIOBase
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r70070 | benjamin.peterson | 2009-02-28 11:06:42 -0600 (Sat, 28 Feb 2009) | 1 line
give credit where credit is due
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r70075 | antoine.pitrou | 2009-02-28 13:34:59 -0600 (Sat, 28 Feb 2009) | 3 lines
Amaury's name
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r70112 | antoine.pitrou | 2009-03-02 17:11:55 -0600 (Mon, 02 Mar 2009) | 4 lines
Looks like this is necessary in order to build cleanly under Windows
(someone correct this if it's wrong, I'm no Windows user)
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r70133 | benjamin.peterson | 2009-03-03 15:23:32 -0600 (Tue, 03 Mar 2009) | 1 line
fix test_newline_property on _pyio.StringIO
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r70135 | benjamin.peterson | 2009-03-03 15:47:30 -0600 (Tue, 03 Mar 2009) | 1 line
fix typos and inconsistencies. thanks to Daniel Diniz
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r70140 | benjamin.peterson | 2009-03-03 16:21:10 -0600 (Tue, 03 Mar 2009) | 1 line
add the test from #5266
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svn+ssh://pythondev@svn.python.org/python/trunk
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r70090 | gregory.p.smith | 2009-03-01 21:13:57 -0800 (Sun, 01 Mar 2009) | 3 lines
Adds an optional flags argument to re.split, re.sub and re.subn to be
consistent with the other re module functions.
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svn+ssh://pythondev@svn.python.org/python/trunk
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r70007 | tarek.ziade | 2009-02-27 03:14:35 +0100 (Fri, 27 Feb 2009) | 1 line
more info on long_description
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svn+ssh://pythondev@svn.python.org/python/trunk
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r69803 | georg.brandl | 2009-02-20 01:48:21 -0600 (Fri, 20 Feb 2009) | 1 line
#5327: fix a broken link by joining it.
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r69804 | georg.brandl | 2009-02-20 02:22:21 -0600 (Fri, 20 Feb 2009) | 1 line
At least separate imports from other statements.
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r69805 | georg.brandl | 2009-02-20 02:45:47 -0600 (Fri, 20 Feb 2009) | 2 lines
Fix punctuation.
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r69840 | georg.brandl | 2009-02-21 13:09:40 -0600 (Sat, 21 Feb 2009) | 1 line
#5338, #5339: two types in the API manual.
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r69901 | georg.brandl | 2009-02-23 05:24:46 -0600 (Mon, 23 Feb 2009) | 2 lines
#5349: C++ pure virtuals can also have an implementation.
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r69905 | georg.brandl | 2009-02-23 09:51:27 -0600 (Mon, 23 Feb 2009) | 2 lines
#5352: str.count() counts non-overlapping instances.
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r69907 | georg.brandl | 2009-02-23 12:33:48 -0600 (Mon, 23 Feb 2009) | 1 line
Fix grammar.
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r69924 | benjamin.peterson | 2009-02-23 20:45:35 -0600 (Mon, 23 Feb 2009) | 1 line
update README on running tests
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r69927 | neil.schemenauer | 2009-02-23 22:23:25 -0600 (Mon, 23 Feb 2009) | 1 line
Fix call to os.waitpid, it does not take keyword args.
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r69987 | benjamin.peterson | 2009-02-25 18:30:11 -0600 (Wed, 25 Feb 2009) | 1 line
fix str.format()'s first arg #5371
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This patch by Antoine Pitrou optimizes the bytecode for conditional branches by
merging the following "POP_TOP" instruction into the conditional jump. For
example, the list comprehension "[x for x in l if not x]" produced the
following bytecode:
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 23 (to 32)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
15 JUMP_IF_TRUE 10 (to 28)
18 POP_TOP
19 LOAD_FAST 1 (x)
22 LIST_APPEND 2
25 JUMP_ABSOLUTE 6
>> 28 POP_TOP
29 JUMP_ABSOLUTE 6
>> 32 RETURN_VALUE
but after the patch it produces the following bytecode:
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 18 (to 27)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
15 POP_JUMP_IF_TRUE 6
18 LOAD_FAST 1 (x)
21 LIST_APPEND 2
24 JUMP_ABSOLUTE 6
>> 27 RETURN_VALUE
Notice that not only the code is shorter, but the conditional jump
(POP_JUMP_IF_TRUE) jumps right to the start of the loop instead of going through
the JUMP_ABSOLUTE at the end. "continue" statements are helped
similarly.
Furthermore, the old jump opcodes (JUMP_IF_FALSE, JUMP_IF_TRUE) have been
replaced by two new opcodes:
- JUMP_IF_TRUE_OR_POP, which jumps if true and pops otherwise
- JUMP_IF_FALSE_OR_POP, which jumps if false and pops otherwise
Brett Cannon
Georg Brandl
Raymond Hettinger
Benjamin Peterson
Hirokazu Yamamoto
Gregory P. Smith
Tarek Ziadé
Jeffrey Yasskin