"update version string during build"
#=========================================================
# imports
#=========================================================
from __future__ import with_statement
#core
import os
import re
import time
from distutils.dist import Distribution
#pkg
#local
__all__ = [
    "stamp_source",
    "stamp_distutils_output",
]
#=========================================================
# helpers
#=========================================================
def get_command_class(opts, name):
    return opts['cmdclass'].get(name) or Distribution().get_command_class(name)

def stamp_source(base_dir, version, dry_run=False):
    "update version string in passlib dist"
    path = os.path.join(base_dir, "passlib", "__init__.py")
    with open(path) as fh:
        input = fh.read()
    output = re.sub('(?m)^__version__\s*=.*$',
                    '__version__ = ' + repr(version),
                    input)
    assert output != input, "failed to match"
    if not dry_run:
        os.unlink(path) # sdist likes to use hardlinks
        with open(path, "w") as fh:
            fh.write(output)
   
def stamp_distutils_output(opts, version):
   
    # subclass buildpy to update version string in source
    _build_py = get_command_class(opts, "build_py")
    class build_py(_build_py):
        def build_packages(self):
            _build_py.build_packages(self)
            stamp_source(self.build_lib, version, self.dry_run)            
    opts['cmdclass']['build_py'] = build_py
    
    # subclass sdist to do same thing
    _sdist = get_command_class(opts, "sdist")
    class sdist(_sdist):        
        def make_release_tree(self, base_dir, files):
            _sdist.make_release_tree(self, base_dir, files)
            stamp_source(base_dir, version, self.dry_run)
    opts['cmdclass']['sdist'] = sdist
    
#=========================================================
# eof
#=========================================================