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=== setuptools includes Jython trunk support as of version 0.6c8! ===

Setuptools trunk and its 0.6 branch have had [[http://svn.python.org/view?rev=60062&view=rev|a couple of changes]] (discussed [[http://mail.python.org/pipermail/distutils-sig/2008-January/008617.html|here on distutils-sig]]) made to fix incompatibilities with Jython.

Even as of these changes, there are a couple improvements that can be made to running setuptools on Jython:

 * Most importantly, the lack of os.chmod. chmod can be implemented with JNA. setuptools simply avoids chmod if it does not exist as of '''''[[http://svn.python.org/view?rev=60062&view=rev|r60062]])'''''

 * setuptools' use of marshal: setuptools uses marshal.load in two places -- to get a code object from a .pyc file, so it can scan the code object's co_names and co_consts (basically to read a module's variables without importing it). This isn't portable: Jython's compiled .pys (actually Java .class files) can't be read via marshal, nor do Jython's code objects support co_names and co_consts

  the two places this is used:

  1. when a package doesn't mark itself as zip_safe, setuptools will scan it for special variable names (like '__file__') to determine zip_safetyness. '''''(setuptools defaults to zip_safe=False for archives that don't set it as of [[http://svn.python.org/view?rev=60062&view=rev|r60062]])'''''

  We could get around the lack of marshal compatibility here by using the tokenize module to read the source code. This wouldn't work in the rare case of a byte-code only egg.
  2. setuptools.depend.get_module_constant: a generic way to grab the value of a module variable. currently only used by Require.get_version '''''setuptools.depend is experimental, unsupported functionality that we don't need to worry about'''''
 * We should consider making the -E command line argument disable the registry

The Jython changes made for setuptools:

 * PEP 302 style zipimport module '''''Added in r3463'''''
 * number of misc. Jython bug fixes '''''most already committed'''''

 * file descriptor support for tempfile.mkstemp, os.open and tarfile '''''Added in r3711'''''
 * tempfile.mkstemp '''''Added in r3712'''''

 * os.chdir (also needed for distutils) '''''Added in r3844'''''
 * tarfile module '''''Added in r3850'''''

 * a valid sys.executable. required by setuptools and distutils for spawning subprocesses. '''''Added in r3867, enabled via -Dpython.executable (see http://article.gmane.org/gmane.comp.lang.jython.devel/4068 )'''''

 * a site-packages dir (jython needs to include it on sys.path by default). required by setuptools and distutils '''''Added in r3886'''''

 * distutils: requires [[http://hg.underboss.org/jython-pjenvey/rev/1026fe32c01c|a number of small patches]]:
  * a valid sys.executable '''''Added in r3867'''''

  * getpass module '''''Added in r3876'''''

  * distutils metadata for the os.name == 'java' (like path names, default bdist type, etc)
  * a jython spawn-like function: "error: don't know how to spawn programs on platform 'java'". os.system works as a replacement

  * compile .py files to $py.class instead of .pyc '''''distutils and these last 3 modifications were added in r3888'''''

 * imp.acquire/release_lock (and the accompanying lock_held which we don't actually need). Exposes the import machinery's lock via the imp module '''''Added in r3894'''''

 * setuptools runs a test to ensure .pth files work by running "sys.executable -E -c pass". -E is ignore environment on CPython, but is different on Jython (takes an argument):
  -E codec : Use a different codec the reading from the console. '''''-E codec renamed to -C codec in r4013. -E is now a noop (but valid) command line arg'''''

 * os.lstat. setuptools cut and pasted shutil's rmtree from CPython 2.4, which uses lstat to check for a directory vs a symlink to a directory. We now support an os.stat that fills in st_mode's directory bit, but can we support lstat? (We definitely can with JNA)? Can setuptools avoid lstat completely (requiring a patch)? I don't think Java can safely determine a sym link yet. Java 1.7's JSR 203 (nio part 2) should address this as well as chmod, but we obviously need a solution for Java 1.5 '''''Turned out we can implement a simple lstat in pure Java, added in r4014'''''

 * for Jython on Windows: distutils.filelist.translate_pattern required ntpath to work correctly, and setuptools required chdir to not canonicalize the pathname via java.io.File '''''both issues fixed with usage of ntpath, in r4171'''''