#!/usr/bin/env python

# Copyright (c) 2001-2004, MetaSlash Inc.  All rights reserved.
# Portions Copyright (c) 2005, Google, Inc.  All rights reserved.

"""
Check python source code files for possible errors and print warnings

Contact Info:
  http://pychecker.sourceforge.net/
  pychecker-list@lists.sourceforge.net
"""

import string
import types
import sys
import imp
import os
import glob
import traceback
import re

# see __init__.py for meaning, this must match the version there
LOCAL_MAIN_VERSION = 3


def setupNamespace(path) :
    # remove pychecker if it's the first component, it needs to be last
    if sys.path[0][-9:] == 'pychecker' :
        del sys.path[0]

    # make sure pychecker is last in path, so we can import
    checker_path = os.path.dirname(os.path.dirname(path))
    if checker_path not in sys.path :
        sys.path.append(checker_path)


def setupSysPathForDevelopment():
    import pychecker
    this_module = sys.modules[__name__]
    this_path = os.path.normpath(os.path.dirname(this_module.__file__))
    pkg_path = os.path.normpath(os.path.dirname(pychecker.__file__))
    if pkg_path != this_path:
        # pychecker was probably found in site-packages, insert this
        # directory before the other one so we can do development and run
        # our local version and not the version from site-packages.
        pkg_dir = os.path.dirname(pkg_path)
        i = 0
        for p in sys.path:
            if os.path.normpath(p) == pkg_dir:
                sys.path.insert(i-1, os.path.dirname(this_path))
                break
            i = i + 1
    del sys.modules['pychecker']


if __name__ == '__main__' :
    setupNamespace(sys.argv[0])
    setupSysPathForDevelopment()

from pychecker import utils
from pychecker import printer
from pychecker import warn
from pychecker import OP
from pychecker import Config
from pychecker import function
from pychecker import msgs
from pychecker import pcmodules
from pychecker.Warning import Warning

_cfg = None

# Constants
_DEFAULT_MODULE_TOKENS = ('__builtins__', '__doc__', '__file__', '__name__',
                          '__path__')
_DEFAULT_CLASS_TOKENS = ('__doc__', '__name__', '__module__')

# When using introspection on objects from some C extension modules,
# the interpreter will crash.  Since pychecker exercises these bugs we
# need to blacklist the objects and ignore them.  For more info on how
# to determine what object is causing the crash, search for this
# comment below (ie, it is also several hundred lines down):
#
#     README if interpreter is crashing:

# FIXME: the values should indicate the versions of these modules
# that are broken.  We shouldn't ignore good modules.

_EVIL_C_OBJECTS = {
    'matplotlib.axes.BinOpType': None,  # broken on versions <= 0.83.2

    # broken on versions at least 2.5.5 up to 2.6
    'wx.TheClipboard': None,
    'wx._core.TheClipboard': None,
    'wx._misc.TheClipboard': None,
  }

_VERSION_MISMATCH_ERROR = '''
There seem to be two versions of PyChecker being used.
One is probably in python/site-packages, the other in a local directory.
If you want to run the local version, you must remove the version
from site-packages.  Or you can install the current version
by doing python setup.py install.
'''

def cfg() :
    return utils.cfg()

def _flattenList(list) :
    "Returns a list which contains no lists"

    new_list = []
    for element in list :
        if type(element) == types.ListType :
            new_list.extend(_flattenList(element))
        else :
            new_list.append(element)

    return new_list

def getModules(arg_list) :
    """
    arg_list is a list of arguments to pychecker; arguments can represent
    a module name, a filename, or a wildcard file specification.

    Returns a list of (module name, dirPath) that can be imported, where
    dirPath is the on-disk path to the module name for that argument.

    dirPath can be None (in case the given argument is an actual module).
    """

    new_arguments = []
    for arg in arg_list :
        # is this a wildcard filespec? (necessary for windows)
        if '*' in arg or '?' in arg or '[' in arg :
            arg = glob.glob(arg)
        new_arguments.append(arg)

    PY_SUFFIXES = ['.py']
    PY_SUFFIX_LENS = [3]
    if _cfg.quixote:
        PY_SUFFIXES.append('.ptl')
        PY_SUFFIX_LENS.append(4)
        
    modules = []
    for arg in _flattenList(new_arguments) :
        # if arg is an actual module, return None for the directory
        arg_dir = None
        # is it a .py file?
        for suf, suflen in zip(PY_SUFFIXES, PY_SUFFIX_LENS):
            if len(arg) > suflen and arg[-suflen:] == suf:
                arg_dir = os.path.dirname(arg)
                if arg_dir and not os.path.exists(arg) :
                    print 'File or pathname element does not exist: "%s"' % arg
                    continue

                module_name = os.path.basename(arg)[:-suflen]

                arg = module_name
        modules.append((arg, arg_dir))

    return modules

def _q_file(f):
    # crude hack!!!
    # imp.load_module requires a real file object, so we can't just
    # fiddle def lines and yield them
    import tempfile
    fd, newfname = tempfile.mkstemp(suffix=".py", text=True)
    newf = os.fdopen(fd, 'r+')
    os.unlink(newfname)
    for line in f:
        mat = re.match(r'(\s*def\s+\w+\s*)\[(html|plain)\](.*)', line)
        if mat is None:
            newf.write(line)
        else:
            newf.write(mat.group(1)+mat.group(3)+'\n')
    newf.seek(0)
    return newf

def _q_find_module(p, path):
    if not _cfg.quixote:
        return imp.find_module(p, path)
    else:
        for direc in path:
            try:
                return imp.find_module(p, [direc])
            except ImportError:
                f = os.path.join(direc, p+".ptl")
                if os.path.exists(f):
                    return _q_file(file(f)), f, ('.ptl', 'U', 1)

def _findModule(name, moduleDir=None) :
    """Returns the result of an imp.find_module(), ie, (file, filename, smt)
       name can be a module or a package name.  It is *not* a filename."""

    path = sys.path[:]
    if moduleDir:
        path.insert(0, moduleDir)

    packages = string.split(name, '.')
    for p in packages :
        # smt = (suffix, mode, type)
        file, filename, smt = _q_find_module(p, path)
        if smt[-1] == imp.PKG_DIRECTORY :
            try :
                # package found - read path info from init file
                m = imp.load_module(p, file, filename, smt)
            finally :
                if file is not None :
                    file.close()

            # importing xml plays a trick, which replaces itself with _xmlplus
            # both have subdirs w/same name, but different modules in them
            # we need to choose the real (replaced) version
            if m.__name__ != p :
                try :
                    file, filename, smt = _q_find_module(m.__name__, path)
                    m = imp.load_module(p, file, filename, smt)
                finally :
                    if file is not None :
                        file.close()

            new_path = m.__path__
            if type(new_path) == types.ListType :
                new_path = filename
            if new_path not in path :
                path.insert(1, new_path)
        elif smt[-1] != imp.PY_COMPILED:
            if p is not packages[-1] :
                if file is not None :
                    file.close()
                raise ImportError, "No module named %s" % packages[-1]
            return file, filename, smt

    # in case we have been given a package to check
    return file, filename, smt


class Variable :
    "Class to hold all information about a variable"

    def __init__(self, name, type):
        self.name = name
        self.type = type
        self.value = None

    def __str__(self) :
        return self.name

    __repr__ = utils.std_repr


def _filterDir(object, ignoreList) :
    "Return a list of tokens (attributes) in a class, except for ignoreList"

    tokens = dir(object)
    for token in ignoreList :
        if token in tokens :
            tokens.remove(token)
    return tokens

def _getClassTokens(c) :
    return _filterDir(c, _DEFAULT_CLASS_TOKENS)


class Class :
    "Class to hold all information about a class"

    def __init__(self, name, pcmodule) :
        """
        @type pcmodule: PyCheckerModule
        """
        self.name = name
        module = pcmodule.module
        self.classObject = getattr(module, name)

        modname = getattr(self.classObject, '__module__', None)
        if modname is None:
            # hm, some ExtensionClasses don't have a __module__ attribute
            # so try parsing the type output
            typerepr = repr(type(self.classObject))
            mo = re.match("^<type ['\"](.+)['\"]>$", typerepr)
            if mo:
                modname = ".".join(mo.group(1).split(".")[:-1])

        # TODO(nnorwitz): this check for __name__ might not be necessary
        # any more.  Previously we checked objects as if they were classes.
        # This problem is fixed by not adding objects as if they are classes.

        # zope.interface for example has Provides and Declaration that
        # look a lot like class objects but do not have __name__
        if not hasattr(self.classObject, '__name__'):
            if modname not in cfg().blacklist:
                sys.stderr.write("warning: no __name__ attribute "
                                 "for class %s (module name: %s)\n"
                                 % (self.classObject, modname))
            self.classObject.__name__ = name
        # later pychecker code uses this
        self.classObject__name__ = self.classObject.__name__

        self.module = sys.modules.get(modname)
        # if the pcmodule has moduleDir, it means we processed it before,
        # and deleted it from sys.modules
        if not self.module and not pcmodule.moduleDir:
            self.module = module
            if modname not in cfg().blacklist:
                sys.stderr.write("warning: couldn't find real module "
                                 "for class %s (module name: %s)\n"
                                 % (self.classObject, modname))
        self.ignoreAttrs = 0
        self.methods = {}
        self.members = { '__class__': types.ClassType,
                         '__doc__': types.StringType,
                         '__dict__': types.DictType, }
        self.memberRefs = {}
        self.statics = {}
        self.lineNums = {}

    def __str__(self) :
        return self.name

    __repr__ = utils.std_repr

    def getFirstLine(self) :
        "Return first line we can find in THIS class, not any base classes"

        lineNums = []
        classDir = dir(self.classObject)
        for m in self.methods.values() :
            if m != None and m.function.func_code.co_name in classDir:
                lineNums.append(m.function.func_code.co_firstlineno)
        if lineNums :
            return min(lineNums)
        return 0

    def allBaseClasses(self, c = None) :
        "Return a list of all base classes for this class and it's subclasses"

        baseClasses = []
        if c == None :
            c = self.classObject
        for base in getattr(c, '__bases__', None) or ():
            baseClasses = baseClasses + [ base ] + self.allBaseClasses(base)
        return baseClasses

    def __getMethodName(self, func_name, className = None) :
        if func_name[0:2] == '__' and func_name[-2:] != '__' :
            if className == None :
                className = self.name
            if className[0] != '_' :
                className = '_' + className
            func_name = className + func_name
        return func_name

    def addMethod(self, method, methodName = None) :
        if type(method) == types.StringType :
            self.methods[method] = None
        else :
            assert methodName is not None, "must supply methodName"
            self.methods[methodName] = function.Function(method, 1)
                
    def addMethods(self, classObject) :
        for classToken in _getClassTokens(classObject) :
            token = getattr(classObject, classToken, None)
            if token is None:
                continue

            # Looks like a method.  Need to code it this way to
            # accommodate ExtensionClass and Python 2.2.  Yecchh.
            if (hasattr(token, "func_code") and
                hasattr(token.func_code, "co_argcount")): 
                self.addMethod(token, token.__name__)

            elif hasattr(token, '__get__') and \
                 not hasattr(token, '__set__') and \
                 type(token) is not types.ClassType :
                self.addMethod(getattr(token, '__name__', classToken))
            else :
                self.members[classToken] = type(token)
                self.memberRefs[classToken] = None

        self.cleanupMemberRefs()
        # add standard methods
        for methodName in ('__class__',) :
            self.addMethod(methodName, self.classObject__name__)

    def addMembers(self, classObject) :
        if not cfg().onlyCheckInitForMembers :
            for classToken in _getClassTokens(classObject) :
                method = getattr(classObject, classToken, None)
                if type(method) == types.MethodType :
                    self.addMembersFromMethod(method.im_func)
        else:
            try:
                self.addMembersFromMethod(classObject.__init__.im_func)
            except AttributeError:
                pass

    def addMembersFromMethod(self, method) :
        if not hasattr(method, 'func_code') :
            return

        func_code, code, i, maxCode, extended_arg = OP.initFuncCode(method)
        stack = []
        while i < maxCode :
            op, oparg, i, extended_arg = OP.getInfo(code, i, extended_arg)
            if op >= OP.HAVE_ARGUMENT :
                operand = OP.getOperand(op, func_code, oparg)
                if OP.LOAD_CONST(op) or OP.LOAD_FAST(op) or OP.LOAD_GLOBAL(op):
                    stack.append(operand)
                elif OP.LOAD_DEREF(op):
                    try:
                        operand = func_code.co_cellvars[oparg]
                    except IndexError:
                        index = oparg - len(func_code.co_cellvars)
                        operand = func_code.co_freevars[index]
                    stack.append(operand)
                elif OP.STORE_ATTR(op) :
                    if len(stack) > 0 :
                        if stack[-1] == cfg().methodArgName:
                            value = None
                            if len(stack) > 1 :
                                value = type(stack[-2])
                            self.members[operand] = value
                            self.memberRefs[operand] = None
                        stack = []

        self.cleanupMemberRefs()

    def cleanupMemberRefs(self) :
        try :
            del self.memberRefs[Config.CHECKER_VAR]
        except KeyError :
            pass

    def abstractMethod(self, m):
        """Return 1 if method is abstract, None if not
           An abstract method always raises an exception.
        """
        if not self.methods.get(m, None):
            return None
        func_code, bytes, i, maxCode, extended_arg = \
                   OP.initFuncCode(self.methods[m].function)
        # abstract if the first opcode is RAISE_VARARGS and it raises
        # NotImplementedError
        arg = ""
        while i < maxCode:
            op, oparg, i, extended_arg = OP.getInfo(bytes, i, extended_arg)
            if OP.LOAD_GLOBAL(op):
                arg = func_code.co_names[oparg]
            elif OP.RAISE_VARARGS(op):
                # if we saw NotImplementedError sometime before the raise
                # assume it's related to this raise stmt
                return arg == "NotImplementedError"
            if OP.conditional(op):
                break
        return None

    def isAbstract(self):
        """Return the method names that make a class abstract.
           An abstract class has at least one abstract method."""
        result = []
        for m in self.methods.keys():
            if self.abstractMethod(m):
                result.append(m)
        return result

def _getLineInFile(moduleName, moduleDir, linenum):
    line = ''
    file, filename, smt = _findModule(moduleName, moduleDir)
    if file is None:
        return ''
    try:
        lines = file.readlines()
        line = string.rstrip(lines[linenum - 1])
    except (IOError, IndexError):
        pass
    file.close()
    return line

def importError(moduleName, moduleDir=None):
    exc_type, exc_value, tb = sys.exc_info()

    # First, try to get a nice-looking name for this exception type.
    exc_name = getattr(exc_type, '__name__', None)
    if not exc_name:
        # either it's a string exception or a user-defined exception class
        # show string or fully-qualified class name
        exc_name = utils.safestr(exc_type)
        
    # Print a traceback, unless this is an ImportError.  ImportError is
    # presumably the most common import-time exception, so this saves
    # the clutter of a traceback most of the time.  Also, the locus of
    # the error is usually irrelevant for ImportError, so the lack of
    # traceback shouldn't be a problem.
    if exc_type is SyntaxError:
        # SyntaxErrors are special, we want to control how we format
        # the output and make it consistent for all versions of Python
        e = exc_value
        msg = '%s (%s, line %d)' % (e.msg, e.filename, e.lineno)
        line = _getLineInFile(moduleName, moduleDir, e.lineno)
        offset = e.offset
        if type(offset) is not types.IntType:
            offset = 0
        exc_value = '%s\n    %s\n   %s^' % (msg, line, ' ' * offset)
    elif exc_type is not ImportError:
        sys.stderr.write("  Caught exception importing module %s:\n" %
                         moduleName)

        try:
            tbinfo = traceback.extract_tb(tb)
        except:
            tbinfo = []
            sys.stderr.write("      Unable to format traceback\n")
        for filename, line, func, text in tbinfo[1:]:
            sys.stderr.write("    File \"%s\", line %d" % (filename, line))
            if func != "?":
                sys.stderr.write(", in %s()" % func)
            sys.stderr.write("\n")
            if text:
                sys.stderr.write("      %s\n" % text)

    # And finally print the exception type and value.
    # Careful formatting exc_value -- can fail for some user exceptions
    sys.stderr.write("  %s: " % exc_name)
    try:
        sys.stderr.write(utils.safestr(exc_value) + '\n')
    except:
        sys.stderr.write('**error formatting exception value**\n')


def _getPyFile(filename):
    """Return the file and '.py' filename from a filename which could
    end with .py, .pyc, or .pyo"""

    if filename[-1] in 'oc' and filename[-4:-1] == '.py':
        return filename[:-1]
    return filename

class PyCheckerModule :
    "Class to hold all information for a module"

    def __init__(self, moduleName, check = 1, moduleDir=None) :
        """
        @param moduleDir: if specified, the directory where the module can
                          be loaded from; allows discerning between modules
                          with the same name in a different directory

        """
        self.moduleName = moduleName
        self.moduleDir = moduleDir
        self.variables = {}
        self.functions = {}
        self.classes = {}
        self.modules = {}
        self.moduleLineNums = {}
        self.attributes = [ '__dict__' ]
        self.main_code = None
        self.module = None
        self.check = check
        # key on a combination of moduleName and moduleDir so we have separate
        # entries for modules with the same name but in different directories
        pcmodules.addPCModule(self)

    def __str__(self) :
        return self.moduleName

    __repr__ = utils.std_repr

    def addVariable(self, var, varType) :
        self.variables[var] = Variable(var, varType)

    def addFunction(self, func) :
        self.functions[func.__name__] = function.Function(func)

    def __addAttributes(self, c, classObject) :
        for base in getattr(classObject, '__bases__', None) or ():
            self.__addAttributes(c, base)
        c.addMethods(classObject)
        c.addMembers(classObject)

    def addClass(self, name) :
        self.classes[name] = c = Class(name, self)
        try:
            objName = utils.safestr(c.classObject)
        except TypeError:
            # this can happen if there is a goofy __getattr__
            c.ignoreAttrs = 1
        else:
            packages = string.split(objName, '.')
            c.ignoreAttrs = packages[0] in cfg().blacklist
        if not c.ignoreAttrs :
            self.__addAttributes(c, c.classObject)

    def addModule(self, name, moduleDir=None) :
        module = pcmodules.getPCModule(name, moduleDir)
        if module is None :
            self.modules[name] = module = PyCheckerModule(name, 0)
            if imp.is_builtin(name) == 0:
                module.load()
            else :
                globalModule = globals().get(name)
                if globalModule :
                    module.attributes.extend(dir(globalModule))
        else :
            self.modules[name] = module

    def filename(self) :
        try :
            filename = self.module.__file__
        except AttributeError :
            filename = self.moduleName
            # FIXME: this would be nice to have, but changes output of
            # NOT PROCESSED UNABLE TO IMPORT like in test8
            #if self.moduleDir:
            #    filename = self.moduleDir + ': ' + filename

        return _getPyFile(filename)

    def load(self):
        try :
            # there's no need to reload modules we already have if no moduleDir
            # is specified for this module
            if not self.moduleDir:
                module = sys.modules.get(self.moduleName)
                if module :
                    if not pcmodules.getPCModule(self.moduleName).module :
                        return self._initModule(module)
                    return 1

            return self._initModule(self.setupMainCode())
        except (SystemExit, KeyboardInterrupt) :
            exc_type, exc_value, exc_tb = sys.exc_info()
            raise exc_type, exc_value
        except :
            importError(self.moduleName, self.moduleDir)
            return cfg().ignoreImportErrors

    def initModule(self, module) :
        if not self.module:
            filename = _getPyFile(module.__file__)
            if string.lower(filename[-3:]) == '.py':
                try:
                    file = open(filename)
                except IOError:
                    pass
                else:
                    self._setupMainCode(file, filename, module)
            return self._initModule(module)
        return 1

    def _initModule(self, module):
        self.module = module
        self.attributes = dir(self.module)

        pychecker_attr = getattr(module, Config.CHECKER_VAR, None)
        if pychecker_attr is not None :
            utils.pushConfig()
            utils.updateCheckerArgs(pychecker_attr, 'suppressions', 0, [])

        for tokenName in _filterDir(self.module, _DEFAULT_MODULE_TOKENS) :
            if _EVIL_C_OBJECTS.has_key('%s.%s' % (self.moduleName, tokenName)):
                continue

            # README if interpreter is crashing:
            # Change 0 to 1 if the interpretter is crashing and re-run.
            # Follow the instructions from the last line printed.
            if _cfg.findEvil:
                print "Add the following line to _EVIL_C_OBJECTS or the string to evil in a config file:\n" \
                      "    '%s.%s': None, " % (self.moduleName, tokenName)

            token = getattr(self.module, tokenName)
            if isinstance(token, types.ModuleType) :
                # get the real module name, tokenName could be an alias
                self.addModule(token.__name__)
            elif isinstance(token, types.FunctionType) :
                self.addFunction(token)
            elif isinstance(token, types.ClassType) or \
                 hasattr(token, '__bases__') and \
                 issubclass(type(token), type):
                self.addClass(tokenName)
            else :
                self.addVariable(tokenName, type(token))

        if pychecker_attr is not None :
            utils.popConfig()
        return 1

    def setupMainCode(self) :
        file, filename, smt = _findModule(self.moduleName, self.moduleDir)
        # FIXME: if the smt[-1] == imp.PKG_DIRECTORY : load __all__
        # HACK: to make sibling imports work, we add self.moduleDir to sys.path
        # temporarily, and remove it later
        if self.moduleDir:
            oldsyspath = sys.path[:]
            sys.path.insert(0, self.moduleDir)
        module = imp.load_module(self.moduleName, file, filename, smt)
        if self.moduleDir:
            sys.path = oldsyspath
            # to make sure that subsequent modules with the same moduleName
            # do not persist, and get their namespace clobbered, delete it
            del sys.modules[self.moduleName]

        self._setupMainCode(file, filename, module)
        return module

    def _setupMainCode(self, file, filename, module):
        try :
            self.main_code = function.create_from_file(file, filename, module)
        finally :
            if file != None :
                file.close()


def getAllModules() :
    "Returns a list of all modules that should be checked."
    modules = []
    for module in pcmodules.getPCModules():
        if module.check :
            modules.append(module)
    return modules

_BUILTIN_MODULE_ATTRS = { 'sys': [ 'ps1', 'ps2', 'tracebacklimit', 
                                   'exc_type', 'exc_value', 'exc_traceback',
                                   'last_type', 'last_value', 'last_traceback',
                                 ],
                        }

def fixupBuiltinModules(needs_init=0):
    for moduleName in sys.builtin_module_names :
        # Skip sys since it will reset sys.stdout in IDLE and cause
        # stdout to go to the real console rather than the IDLE console.
        # FIXME: this breaks test42
        # if moduleName == 'sys':
        #     continue

        if needs_init:
            _ = PyCheckerModule(moduleName, 0)
        # builtin modules don't have a moduleDir
        module = pcmodules.getPCModule(moduleName)
        if module is not None :
            try :
                m = imp.init_builtin(moduleName)
            except ImportError :
                pass
            else :
                extra_attrs = _BUILTIN_MODULE_ATTRS.get(moduleName, [])
                module.attributes = [ '__dict__' ] + dir(m) + extra_attrs


def _printWarnings(warnings, stream=None):
    if stream is None:
        stream = sys.stdout
    
    warnings.sort()
    lastWarning = None
    for warning in warnings :
        if lastWarning is not None:
            # ignore duplicate warnings
            if cmp(lastWarning, warning) == 0:
                continue
            # print blank line between files
            if lastWarning.file != warning.file:
                stream.write("\n")

        lastWarning = warning
        warning.output(stream)


class NullModule:
    def __getattr__(self, unused_attr):
        return None

def install_ignore__import__():

    _orig__import__ = None

    def __import__(name, globals=None, locals=None, fromlist=None):
        if globals is None:
            globals = {}
        if locals is None:
            locals = {}
        if fromlist is None:
            fromlist = ()

        try:
            pymodule = _orig__import__(name, globals, locals, fromlist)
        except ImportError:
            pymodule = NullModule()
            if not _cfg.quiet:
                modname = '.'.join((name,) + fromlist)
                sys.stderr.write("Can't import module: %s, ignoring.\n" % modname)
        return pymodule

    # keep the orig __import__ around so we can call it
    import __builtin__
    _orig__import__ = __builtin__.__import__
    __builtin__.__import__ = __import__

def processFiles(files, cfg = None, pre_process_cb = None) :
    # insert this here, so we find files in the local dir before std library
    if sys.path[0] != '' :
        sys.path.insert(0, '')

    # ensure we have a config object, it's necessary
    global _cfg
    if cfg is not None :
        _cfg = cfg
    elif _cfg is None :
        _cfg = Config.Config()

    if _cfg.ignoreImportErrors:
        install_ignore__import__()

    warnings = []
    utils.initConfig(_cfg)
    for file, (moduleName, moduleDir) in zip(files, getModules(files)) :
        if callable(pre_process_cb) :
            pre_process_cb("module %s (%s)" % (moduleName, file))
        oldsyspath = sys.path[:]
        sys.path.insert(0, moduleDir)
        module = PyCheckerModule(moduleName, moduleDir=moduleDir)
        if not module.load() :
            w = Warning(module.filename(), 1,
                        msgs.Internal("NOT PROCESSED UNABLE TO IMPORT"))
            warnings.append(w)
        sys.path = oldsyspath
    utils.popConfig()
    return warnings


def getWarnings(files, cfg = None, suppressions = None):
    warnings = processFiles(files, cfg)
    fixupBuiltinModules()
    return warnings + warn.find(getAllModules(), _cfg, suppressions)


def _print_processing(name) :
    if not _cfg.quiet :
        sys.stderr.write("Processing %s...\n" % name)


def main(argv) :
    __pychecker__ = 'no-miximport'
    import pychecker
    if LOCAL_MAIN_VERSION != pychecker.MAIN_MODULE_VERSION :
        sys.stderr.write(_VERSION_MISMATCH_ERROR)
        sys.exit(100)

    # remove empty arguments
    argv = filter(None, argv)
        
    # if the first arg starts with an @, read options from the file
    # after the @ (this is mostly for windows)
    if len(argv) >= 2 and argv[1][0] == '@':
        # read data from the file
        command_file = argv[1][1:]
        try:
            f = open(command_file, 'r')
            command_line = f.read()
            f.close()
        except IOError, err:
            sys.stderr.write("Unable to read commands from file: %s\n  %s\n" % \
                             (command_file, err))
            sys.exit(101)

        # convert to an argv list, keeping argv[0] and the files to process
        argv = argv[:1] + string.split(command_line) + argv[2:]
 
    global _cfg
    _cfg, files, suppressions = Config.setupFromArgs(argv[1:])
    if not files :
        return 0

    # Now that we've got the args, update the list of evil C objects
    for evil_doer in _cfg.evil:
        _EVIL_C_OBJECTS[evil_doer] = None

    # insert this here, so we find files in the local dir before std library
    sys.path.insert(0, '')

    importWarnings = processFiles(files, _cfg, _print_processing)
    fixupBuiltinModules()
    if _cfg.printParse :
        for module in getAllModules() :
            printer.module(module)

    warnings = warn.find(getAllModules(), _cfg, suppressions)
    if not _cfg.quiet :
        print "\nWarnings...\n"
    if warnings or importWarnings :
        _printWarnings(importWarnings + warnings)
        return 1

    if not _cfg.quiet :
        print "None"
    return 0


if __name__ == '__main__' :
    try :
        sys.exit(main(sys.argv))
    except Config.UsageError :
        sys.exit(127)

else :
    _orig__import__ = None
    _suppressions = None
    _warnings_cache = {}

    def _get_unique_warnings(warnings):
        for i in range(len(warnings)-1, -1, -1):
            w = warnings[i].format()
            if _warnings_cache.has_key(w):
                del warnings[i]
            else:
                _warnings_cache[w] = 1
        return warnings

    def __import__(name, globals=None, locals=None, fromlist=None):
        if globals is None:
            globals = {}
        if locals is None:
            locals = {}
        if fromlist is None:
            fromlist = []

        check = not sys.modules.has_key(name) and name[:10] != 'pychecker.'
        pymodule = _orig__import__(name, globals, locals, fromlist)
        if check :
            try :
                # FIXME: can we find a good moduleDir ?
                module = PyCheckerModule(pymodule.__name__)
                if module.initModule(pymodule):
                    warnings = warn.find([module], _cfg, _suppressions)
                    _printWarnings(_get_unique_warnings(warnings))
                else :
                    print 'Unable to load module', pymodule.__name__
            except Exception:
                name = getattr(pymodule, '__name__', utils.safestr(pymodule))
                # FIXME: can we use it here ?
                importError(name)

        return pymodule

    def _init() :
        global _cfg, _suppressions, _orig__import__

        args = string.split(os.environ.get('PYCHECKER', ''))
        _cfg, files, _suppressions = Config.setupFromArgs(args)
        utils.initConfig(_cfg)
        fixupBuiltinModules(1)

        # keep the orig __import__ around so we can call it
        import __builtin__
        _orig__import__ = __builtin__.__import__
        __builtin__.__import__ = __import__

    if not os.environ.get('PYCHECKER_DISABLED') :
        _init()