UtilitiesPython2/Py2SyntaxChecker.py

# -*- coding: utf-8 -*-

# Copyright (c) 2011 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing the syntax check for Python 2.
"""

import sys
import re
import traceback
from codecs import BOM_UTF8, BOM_UTF16, BOM_UTF32

coding_regexps = [
    (2, re.compile(r'''coding[:=]\s*([-\w_.]+)''')), 
    (1, re.compile(r'''<\?xml.*\bencoding\s*=\s*['"]([-\w_.]+)['"]\?>''')), 
]

def get_coding(text):
    """
    Function to get the coding of a text.
    
    @param text text to inspect (string)
    @return coding string
    """
    lines = text.splitlines()
    for coding in coding_regexps:
        coding_re = coding[1]
        head = lines[:coding[0]]
        for l in head:
            m = coding_re.search(l)
            if m:
                return m.group(1).lower()
    return None

def decode(text):
    """
    Function to decode a text.
    
    @param text text to decode (string)
    @return decoded text and encoding
    """
    try:
        if text.startswith(BOM_UTF8):
            # UTF-8 with BOM
            return unicode(text[len(BOM_UTF8):], 'utf-8'), 'utf-8-bom'
        elif text.startswith(BOM_UTF16):
            # UTF-16 with BOM
            return unicode(text[len(BOM_UTF16):], 'utf-16'), 'utf-16'
        elif text.startswith(BOM_UTF32):
            # UTF-32 with BOM
            return unicode(text[len(BOM_UTF32):], 'utf-32'), 'utf-32'
        coding = get_coding(text)
        if coding:
            return unicode(text, coding), coding
    except (UnicodeError, LookupError):
        pass
    
    # Assume UTF-8
    try:
        return unicode(text, 'utf-8'), 'utf-8-guessed'
    except (UnicodeError, LookupError):
        pass
    
    # Assume Latin-1 (behaviour before 3.7.1)
    return unicode(text, "latin-1"), 'latin-1-guessed'

def compile(file):
    """
    Function to compile one Python source file to Python bytecode.
    
    @param file source filename (string)
    @return A tuple indicating status (1 = an error was found), the
        filename, the linenumber, the code string and the error message
        (boolean, string, string, string, string). The values are only
        valid, if the status equals 1.
    """
    import __builtin__
    try:
        f = open(file)
        codestring, encoding = decode(f.read())
        f.close()
    except IOError, msg:
        return (1, file, "1", "", "I/O Error: %s" % unicode(msg))

    if type(codestring) == type(u""):
        codestring = codestring.encode('utf-8')
    codestring = codestring.replace("\r\n","\n")
    codestring = codestring.replace("\r","\n")

    if codestring and codestring[-1] != '\n':
        codestring = codestring + '\n'
    
    try:
        if type(file) == type(u""):
            file = file.encode('utf-8')
        
        if file.endswith('.ptl'):
            try:
                import quixote.ptl_compile
            except ImportError:
                return (0, None, None, None, None)
            template = quixote.ptl_compile.Template(codestring, file)
            template.compile()
            codeobject = template.code
        else:
            codeobject = __builtin__.compile(codestring, file, 'exec')
    except SyntaxError, detail:
        lines = traceback.format_exception_only(SyntaxError, detail)
        match = re.match('\s*File "(.+)", line (\d+)', 
            lines[0].replace('<string>', '%s' % file))
        if match is not None:
            fn, line = match.group(1, 2)
            if lines[1].startswith('SyntaxError:'):
                code = ""
                error = re.match('SyntaxError: (.+)', lines[1]).group(1)
            else:
                code = re.match('(.+)', lines[1]).group(1)
                error = ""
                for seLine in lines[2:]:
                    if seLine.startswith('SyntaxError:'):
                        error = re.match('SyntaxError: (.+)', seLine).group(1)
        else:
            fn = detail.filename
            line = detail.lineno and detail.lineno or 1
            code = ""
            error = detail.msg
        return (1, fn, line, code, error)
    except ValueError, detail:
        try:
            fn = detail.filename
            line = detail.lineno
            error = detail.msg
        except AttributeError:
            fn = file
            line = 1
            error = unicode(detail)
        code = ""
        return (1, fn, line, code, error)
    except StandardError, detail:
        try:
            fn = detail.filename
            line = detail.lineno
            code = ""
            error = detail.msg
            return (1, fn, line, code, error)
        except:         # this catchall is intentional
            pass
    
    return (0, None, None, None, None)

if __name__ == "__main__":
    if len(sys.argv) != 2:
        print "ERROR"
        print ""
        print ""
        print ""
        print "No file name given."
    else:
        filename = sys.argv[1]
        res, fname, line, code, error = compile(filename)
        
        if res:
            print "ERROR"
        else:
            print "NO_ERROR"
        print fname
        print line
        print code
        print error
    
    sys.exit(0)
    
#
# eflag: FileType = Python2