ini: only keep default value as comment if the custom value actually is different

kallithea/lib/inifile.py

@@ -1,160 +1,162 b''
 # -*- coding: utf-8 -*-
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program 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
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 """
 kallithea.lib.inifile
 ~~~~~~~~~~~~~~~~~~~~~
 
 Handling of .ini files, mainly creating them from Mako templates and adding
 other custom values.
 """
 
 import logging
 import re
 import os
 
 import mako.template
 
 
 log = logging.getLogger(__name__)
 
 
 template_file = os.path.join(
     os.path.dirname(os.path.dirname(os.path.dirname(__file__))),
     'kallithea/lib/paster_commands/template.ini.mako')
 
 default_variables = {
     'database_engine': 'sqlite',
     'http_server': 'waitress',
     'host': '127.0.0.1',
     'port': '5000',
     'uuid': lambda: 'VERY-SECRET',
 }
 
 
 def expand(template, mako_variable_values, settings):
     """Expand mako template and tweak it.
     Not entirely stable for random templates as input, but good enough for our
     single template.
 
     >>> template = '''
     ... [first-section]
     ...
     ... variable=${mako_variable}
     ... variable2  =\tvalue after tab
     ... ## This section had some whitespace and stuff
     ...
     ...
     ... # ${mako_function()}
     ... [second-section]
     ... %if conditional_options == 'option-a':
     ... # option a was chosen
     ... %elif conditional_options == 'option-b':
     ... some_variable = "never mind - option-b will not be used anyway ..."
     ... %endif
     ... '''
     >>> selected_mako_conditionals = []
     >>> mako_variable_values = {'mako_variable': 'VALUE', 'mako_function': (lambda: 'FUNCTION RESULT'),
     ...                         'conditional_options': 'option-a'}
     >>> settings = { # only partially used
     ...     '[first-section]': {'variable2': 'VAL2', 'first_extra': 'EXTRA'},
     ...     '[third-section]': {'third_extra': ' 3'},
     ...     '[fourth-section]': {'fourth_extra': '4', 'fourth': '"four"'},
     ... }
     >>> print expand(template, mako_variable_values, settings)
     <BLANKLINE>
     [first-section]
     <BLANKLINE>
     variable=VALUE
     #variable2  =    value after tab
     variable2 = VAL2
     <BLANKLINE>
     first_extra = EXTRA
     <BLANKLINE>
     <BLANKLINE>
     # FUNCTION RESULT
     [second-section]
     # option a was chosen
     <BLANKLINE>
     [fourth-section]
     fourth = "four"
     fourth_extra = 4
     <BLANKLINE>
     [third-section]
     third_extra =  3
     <BLANKLINE>
     """
     mako_variables = dict(default_variables)
     mako_variables.update(mako_variable_values or {})
     settings = dict((k, dict(v)) for k, v in settings.items()) # deep copy before mutating
 
     ini_lines = mako.template.Template(template).render(**mako_variables)
 
     def process_section(m):
         """process a ini section, replacing values as necessary"""
         sectionname, lines = m.groups()
         if sectionname in settings:
             section_settings = settings.pop(sectionname)
 
             def process_line(m):
                 """process a section line and update value if necessary"""
                 key, value = m.groups()
                 line = m.group(0)
                 if key in section_settings:
+                    new_line = '%s = %s' % (key, section_settings.pop(key))
+                    if new_line != line:
                     # keep old entry as example - comments might refer to it
-                    line = '#%s\n%s = %s' % (line, key, section_settings.pop(key))
+                        line = '#%s\n%s' % (line, new_line)
                 return line.rstrip()
 
             # process lines that not are comments or empty and look like name=value
             lines = re.sub(r'^([^#\n\s]*)[ \t]*=[ \t]*(.*)$', process_line, lines, flags=re.MULTILINE)
             # add unused section settings
             if section_settings:
                 lines += '\n' + ''.join('%s = %s\n' % (key, value) for key, value in sorted(section_settings.items()))
 
         return sectionname + '\n' + lines
 
     # process sections until comments before next section or end
     ini_lines = re.sub(r'''^
         (\[.*\])\n
         # after the section name, a number of chunks with:
         (
             (?:
                 # a number of comments or empty lines
                 (?:[#].*\n|\n)*
                 # one or more non-empty non-comments non-section-start lines
                 (?:[^\n#[].*\n)+
                 # a number of comments - not empty lines
                 (?:[#].*\n)*
             )*
         )
         ''',
         process_section, ini_lines, flags=re.MULTILINE|re.VERBOSE) \
         + \
         ''.join(
             '\n' + sectionname + '\n' + ''.join('%s = %s\n' % (key, value) for key, value in sorted(section_settings.items()))
             for sectionname, section_settings in sorted(settings.items())
             if section_settings)
 
     return ini_lines
 
 
 def create(dest_file, mako_variable_values, settings):
     """Create an ini file at dest_file"""
     with open(template_file, 'rb') as f:
         template = f.read().decode('utf-8')
 
     ini_lines = expand(template, mako_variable_values, settings)
 
     with open(dest_file, 'wb') as f:
         f.write(ini_lines.encode('utf-8'))