Fixed #15493 - csrf_migration_helper.py parsing fix.

#   loaders are out of the picture, because there is no way to ask them to

#   return all templates.

#

# - If you put the {% csrf_token %} tag on the same line as the <form> tag it

#   will be detected, otherwise it will be assumed that the form does not have

#   the token.

#

# - It's impossible to programmatically determine which forms should and should

#   not have the token added.  The developer must decide when to do this,

#   ensuring that the token is only added to internally targetted forms.

_POST_FORM_RE = \

    re.compile(r'(<form\W[^>]*\bmethod\s*=\s*(\'|"|)POST(\'|"|)\b[^>]*>)', re.IGNORECASE)

_FORM_CLOSE_RE = re.compile(r'</form\s*>')

_TOKEN_RE = re.compile('\{% csrf_token')

def get_template_dirs():

        Get information about any POST forms in the template.

        Returns [(linenumber, csrf_token added)]

        """

        matches = []

        forms = {}

        form_line = 0

        for ln, line in enumerate(self.content.split("\n")):

            m = _POST_FORM_RE.search(line)

            if m is not None:

                matches.append((ln + 1, _TOKEN_RE.search(line) is not None))

        return matches

            if not form_line and _POST_FORM_RE.search(line):

                # record the form with no CSRF token yet

                form_line = ln + 1

                forms[form_line] = False

            if form_line and _TOKEN_RE.search(line):

                # found the CSRF token

                forms[form_line] = True

                form_line = 0

            if form_line and _FORM_CLOSE_RE.search(line):

                # no token found by form closing tag

                form_line = 0

        return forms.items()

    def includes_template(self, t):

        """