setuptools includes Jython trunk support as of version 0.6c8!

Setuptools trunk and its 0.6 branch have had a couple of changes (discussed 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 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:

  • 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 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.

  • 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 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