Noissue - make line_type in parser.py private and fix its docstring

abp/filters/parser.py

 # This file is part of Adblock Plus <https://adblockplus.org/>,
 # Copyright (C) 2006-2017 eyeo GmbH
 #
 # Adblock Plus is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 3 as
 # published by the Free Software Foundation.
 #
 # Adblock Plus is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
@@ skipping 16 matching lines @@
     :param error: Description of the error.
     :param text: The text which was being parsed when an error occurred.
     """
 
     def __init__(self, error, text):
         Exception.__init__(self, '{} in "{}"'.format(error, text))
         self.text = text
         self.error = error
 
 
-def line_type(name, field_names, format_string):
+def _line_type(name, field_names, format_string):
     """Define a line type.
 
     :param name: The name of the line type to define.
     :param field_names: A sequence of field names or one space-separated
         string that contains all field names.
+    :param format_string: A format specifier for converting this line type
+        back to string representation.
     :returns: Class created with `namedtuple` that has `.type` set to
         lowercased `name` and supports conversion back to string with
         `.to_string()` method.
     """
     lt = namedtuple(name, field_names)
     lt.type = name.lower()
     lt.to_string = lambda self: format_string.format(self)
     return lt
 
 
-Header = line_type('Header', 'version', '[{.version}]')
-EmptyLine = line_type('EmptyLine', '', '')
-Comment = line_type('Comment', 'text', '! {.text}')
-Metadata = line_type('Metadata', 'key value', '! {0.key}: {0.value}')
-Filter = line_type('Filter', 'expression', '{.expression}')
-Include = line_type('Include', 'target', '%include {0.target}%')
+Header = _line_type('Header', 'version', '[{.version}]')
+EmptyLine = _line_type('EmptyLine', '', '')
+Comment = _line_type('Comment', 'text', '! {.text}')
+Metadata = _line_type('Metadata', 'key value', '! {0.key}: {0.value}')
+Filter = _line_type('Filter', 'expression', '{.expression}')
+Include = _line_type('Include', 'target', '%include {0.target}%')
 
 
 METADATA_REGEXP = re.compile(r'!\s*(\w+)\s*:\s*(.*)')
 METADATA_KEYS = {'Homepage', 'Title', 'Expires', 'Checksum', 'Redirect',
                  'Version'}
 INCLUDE_REGEXP = re.compile(r'%include\s+(.+)%')
 HEADER_REGEXP = re.compile(r'\[(Adblock(?:\s*Plus\s*[\d\.]+?)?)\]', flags=re.I)
 
 
 def _parse_comment(text):
@@ skipping 14 matching lines @@
     match = INCLUDE_REGEXP.match(text)
     if not match:
         raise ParseError('Unrecognized instruction', text)
     return Include(match.group(1))
 
 
 def parse_line(line_text):
     """Parse one line of a filter list.
 
     :param line_text: Line of a filter list (must be a unicode string).
-    :returns: Parsed line object (see `line_type`).
+    :returns: Parsed line object (see `_line_type`).
     :raises ParseError: If the line can't be successfully parsed.
     """
     content = line_text.strip()
 
     if content == '':
         line = EmptyLine()
     elif content.startswith('!'):
         line = _parse_comment(content)
     elif content.startswith('%') and content.endswith('%'):
         line = _parse_instruction(content)
     elif content.startswith('[') and content.endswith(']'):
         line = _parse_header(content)
     else:
         line = Filter(content)
 
     assert line.to_string().replace(' ', '') == content.replace(' ', '')
     return line
 
 
 def parse_filterlist(lines):
     """Parse filter list from an iterable.
 
     :param lines: List of strings or file or other iterable.
     :returns: Iterator over parsed lines.
     :raises ParseError: Can be thrown during iteration for invalid lines.
     """
     for line in lines:
         yield parse_line(line)