mercurial/packagescan.py

clone: simplifying dest repo creation

since creating a repo raises an exception if the repo already
exists, there's no need to try to create one.
add some test for repo creation when the destination exists

# packagescan.py - Helper module for identifing used modules.
# Used for the py2exe distutil.
# This module must be the first mercurial module imported in setup.py
#
# Copyright 2005, 2006 Volker Kleinfeld <[e-mail]>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
import glob
import os
import sys
import ihooks
import types
import string

# Install this module as fake demandload module
sys.modules['mercurial.demandload'] = sys.modules[__name__]

# Requiredmodules contains the modules imported by demandload.
# Please note that demandload can be invoked before the
# mercurial.packagescan.scan method is invoked in case a mercurial
# module is imported.
requiredmodules = {}
def demandload(scope, modules):
    """ fake demandload function that collects the required modules
        foo            import foo
        foo bar        import foo, bar
        foo.bar        import foo.bar
        foo@bar        import foo as bar
        foo:bar        from foo import bar
        foo:bar,quux   from foo import bar, quux
        foo.bar:quux   from foo.bar import quux"""

    for m in modules.split():
        mod = None
        try:
            module, fromlist = m.split(':')
            fromlist = fromlist.split(',')
        except:
            module = m
            fromlist = []
        as_ = None
        if '@' in module:
            module, as_ = module.split('@')
        mod = __import__(module, scope, scope, fromlist)
        if fromlist == []:
            # mod is only the top package, but we need all packages
            comp = module.split('.')
            i = 1
            mn = comp[0]
            while True:
                # mn and mod.__name__ might not be the same
                if not as_:
                    as_ = mn
                scope[as_] = mod
                requiredmodules[mod.__name__] = 1
                if len(comp) == i: break
                mod = getattr(mod,comp[i])
                mn = string.join(comp[:i+1],'.')
                i += 1
        else:
            # mod is the last package in the component list
            requiredmodules[mod.__name__] = 1
            for f in fromlist:
                scope[f] = getattr(mod,f)
                if type(scope[f]) == types.ModuleType:
                    requiredmodules[scope[f].__name__] = 1

class SkipPackage(Exception):
    def __init__(self, reason):
        self.reason = reason

scan_in_progress = False

def scan(libpath,packagename):
    """ helper for finding all required modules of package <packagename> """
    global scan_in_progress
    scan_in_progress = True
    # Use the package in the build directory
    libpath = os.path.abspath(libpath)
    sys.path.insert(0,libpath)
    packdir = os.path.join(libpath,packagename.replace('.', '/'))
    # A normal import would not find the package in
    # the build directory. ihook is used to force the import.
    # After the package is imported the import scope for
    # the following imports is settled.
    p = importfrom(packdir)
    globals()[packagename] = p
    sys.modules[packagename] = p
    # Fetch the python modules in the package
    cwd = os.getcwd()
    os.chdir(packdir)
    pymodulefiles = glob.glob('*.py')
    extmodulefiles = glob.glob('*.pyd')
    os.chdir(cwd)
    # Import all python modules and by that run the fake demandload
    for m in pymodulefiles:
        if m == '__init__.py': continue
        tmp = {}
        mname,ext = os.path.splitext(m)
        fullname = packagename+'.'+mname
        try:
            __import__(fullname,tmp,tmp)
        except SkipPackage, inst:
            print >> sys.stderr, 'skipping %s: %s' % (fullname, inst.reason)
            continue
        requiredmodules[fullname] = 1
    # Import all extension modules and by that run the fake demandload
    for m in extmodulefiles:
        tmp = {}
        mname,ext = os.path.splitext(m)
        fullname = packagename+'.'+mname
        __import__(fullname,tmp,tmp)
        requiredmodules[fullname] = 1

def getmodules():
    return requiredmodules.keys()

def importfrom(filename):
    """
    import module/package from a named file and returns the module.
    It does not check on sys.modules or includes the module in the scope.
    """
    loader = ihooks.BasicModuleLoader()
    path, file = os.path.split(filename)
    name, ext  = os.path.splitext(file)
    m = loader.find_module_in_dir(name, path)
    if not m:
        raise ImportError, name
    m = loader.load_module(name, m)
    return m