python类__version__()的实例源码

def has_environment_marker_support():
    #type: () -> bool
    """
    Tests that setuptools has support for PEP-426 environment marker support.
    The first known release to support it is 0.7 (and the earliest on PyPI seems to be 0.7.2
    so we're using that), see: http://pythonhosted.org/setuptools/history.html#id142
    References:
    * https://wheel.readthedocs.io/en/latest/index.html#defining-conditional-dependencies
    * https://www.python.org/dev/peps/pep-0426/#environment-markers
    Method extended from pytest. Credit goes to developers there.
    """
    try:
        from pkg_resources import parse_version
        return parse_version(setuptools.__version__) >= parse_version('0.7.2')
    except Exception as exc:
        sys.stderr.write("Could not test setuptool's version: %s\n" % exc)
        return False

def has_environment_marker_support():
    """
    Tests that setuptools has support for PEP-426 environment marker support.

    The first known release to support it is 0.7 (and the earliest on PyPI seems to be 0.7.2
    so we're using that), see: http://pythonhosted.org/setuptools/history.html#id142

    References:

    * https://wheel.readthedocs.org/en/latest/index.html#defining-conditional-dependencies
    * https://www.python.org/dev/peps/pep-0426/#environment-markers
    """
    import pkg_resources
    try:
        v = pkg_resources.parse_version(setuptools.__version__)
        return v >= pkg_resources.parse_version('0.7.2')
    except Exception as exc:
        sys.stderr.write("Could not test setuptool's version: %s\n" % exc)
        return False

def has_environment_marker_support():
    """
    Tests that setuptools has support for PEP-426 environment marker support.

    The first known release to support it is 0.7 (and the earliest on PyPI seems to be 0.7.2
    so we're using that), see: http://pythonhosted.org/setuptools/history.html#id142

    References:

    * https://wheel.readthedocs.org/en/latest/index.html#defining-conditional-dependencies
    * https://www.python.org/dev/peps/pep-0426/#environment-markers
    """
    try:
        return pkg_resources.parse_version(setuptools.__version__) >= pkg_resources.parse_version('0.7.2')
    except Exception as exc:
        sys.stderr.write("Could not test setuptool's version: %s\n" % exc)
        return False

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            sys.stderr.write(
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script.\n"
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print("Setuptools version",version,"or greater has been installed.")
            print('(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)')

def have_environment_marker_support():
    """
    Check whether setuptools has support for PEP-426 environment marker support.

    Based on the ``setup.py`` script of the ``pytest`` package:
    https://bitbucket.org/pytest-dev/pytest/src/default/setup.py
    """
    try:
        from pkg_resources import parse_version
        from setuptools import __version__
        return parse_version(__version__) >= parse_version('0.7.2')
    except Exception:
        return False

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0, egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
                "You have an obsolete version of setuptools installed."
                " Please remove it from your system entirely before rerunning"
                " this script.")
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0)  # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print ("Setuptools version", version,
                   "or greater has been installed.")
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def dependencies():
    """Generate the list of dependencies we care about."""
    return [{'dependency': 'setuptools', 'version': setuptools.__version__}]

def get_version():
    p = os.path.join(os.path.dirname(
                     os.path.abspath(__file__)), "_pytest", "__init__.py")
    with open(p) as f:
        for line in f.readlines():
            if "__version__" in line:
                return line.strip().split("=")[-1].strip(" '")
    raise ValueError("could not read version")

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def use_setuptools(
    version=DEFAULT_VERSION, download_base=DEFAULT_URL, to_dir=os.curdir,
    download_delay=15
):
    """Automatically find/download setuptools and make it available on sys.path

    `version` should be a valid setuptools version number that is available
    as an egg for download under the `download_base` URL (which should end with
    a '/').  `to_dir` is the directory where setuptools will be downloaded, if
    it is not already available.  If `download_delay` is specified, it should
    be the number of seconds that will be paused before initiating a download,
    should one be required.  If an older version of setuptools is installed,
    this routine will print a message to ``sys.stderr`` and raise SystemExit in
    an attempt to abort the calling script.
    """
    try:
        import setuptools
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)
    except ImportError:
        egg = download_setuptools(version, download_base, to_dir, download_delay)
        sys.path.insert(0, egg)
        import setuptools; setuptools.bootstrap_install_from = egg

    import pkg_resources
    try:
        pkg_resources.require("setuptools>="+version)

    except pkg_resources.VersionConflict, e:
        # XXX could we install in a subprocess here?
        print >>sys.stderr, (
            "The required version of setuptools (>=%s) is not available, and\n"
            "can't be installed while this script is running. Please install\n"
            " a more recent version first.\n\n(Currently using %r)"
        ) % (version, e.args[0])
        sys.exit(2)

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""

    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            # tell the user to uninstall obsolete version
            use_setuptools(version)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'

def main(argv, version=DEFAULT_VERSION):
    """Install or upgrade setuptools and EasyInstall"""
    try:
        import setuptools
    except ImportError:
        egg = None
        try:
            egg = download_setuptools(version, delay=0)
            sys.path.insert(0,egg)
            from setuptools.command.easy_install import main
            return main(list(argv)+[egg])   # we're done here
        finally:
            if egg and os.path.exists(egg):
                os.unlink(egg)
    else:
        if setuptools.__version__ == '0.0.1':
            print >>sys.stderr, (
            "You have an obsolete version of setuptools installed.  Please\n"
            "remove it from your system entirely before rerunning this script."
            )
            sys.exit(2)

    req = "setuptools>="+version
    import pkg_resources
    try:
        pkg_resources.require(req)
    except pkg_resources.VersionConflict:
        try:
            from setuptools.command.easy_install import main
        except ImportError:
            from easy_install import main
        main(list(argv)+[download_setuptools(delay=0)])
        sys.exit(0) # try to force an exit
    else:
        if argv:
            from setuptools.command.easy_install import main
            main(argv)
        else:
            print "Setuptools version",version,"or greater has been installed."
            print '(Run "ez_setup.py -U setuptools" to reinstall or upgrade.)'