#!/usr/bin/env python

"""List all those Python files that require a coding directive

Usage: nocoding.py dir1 [dir2...]

"""

__author__ = "Oleg Broytmann, Georg Brandl"

import sys, os, re, getopt

# our pysource module finds Python source files

try:

    import pysource

except:

    # emulate the module with a simple os.walk

    class pysource:

        has_python_ext = looks_like_python = can_be_compiled = None

        def walk_python_files(self, paths, *args, **kwargs):

            for path in paths:

                if os.path.isfile(path):

                    yield path.endswith(".py")

                elif os.path.isdir(path):

                    for root, dirs, files in os.walk(path):

                        for filename in files:

                            if filename.endswith(".py"):

                                yield os.path.join(root, filename)

    pysource = pysource()

    print >>sys.stderr, ("The pysource module is not available; "

                         "no sophisticated Python source file search will be done.")

decl_re = re.compile(r"coding[=:]\s*([-\w.]+)")

def get_declaration(line):

    match = decl_re.search(line)

    if match:

        return match.group(1)

    return ''

def has_correct_encoding(text, codec):

    try:

        unicode(text, codec)

    except UnicodeDecodeError:

        return False

    else:

        return True

def needs_declaration(fullpath):

    try:

        infile = open(fullpath, 'rU')

    except IOError: # Oops, the file was removed - ignore it

        return None

    line1 = infile.readline()

    line2 = infile.readline()

    if get_declaration(line1) or get_declaration(line2):

        # the file does have an encoding declaration, so trust it

        infile.close()

        return False

    # check the whole file for non-ASCII characters

    rest = infile.read()

    infile.close()

    if has_correct_encoding(line1+line2+rest, "ascii"):

        return False

    return True

usage = """Usage: %s [-cd] paths...

    -c: recognize Python source files trying to compile them

    -d: debug output""" % sys.argv[0]

try:

    opts, args = getopt.getopt(sys.argv[1:], 'cd')

except getopt.error, msg:

    print >>sys.stderr, msg

    print >>sys.stderr, usage

    sys.exit(1)

is_python = pysource.looks_like_python

debug = False

for o, a in opts:

    if o == '-c':

        is_python = pysource.can_be_compiled

    elif o == '-d':

        debug = True

if not args:

    print >>sys.stderr, usage

    sys.exit(1)

for fullpath in pysource.walk_python_files(args, is_python):

    if debug:

        print "Testing for coding: %s" % fullpath

    result = needs_declaration(fullpath)

    if result:

        print fullpath