nitpicker

#!/usr/bin/env python
# Copyright 2014  Lars Wirzenius
#
# 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/>.
#
# =*= License: GPL-3+ =*=


import sys

import cliapp

import obnamlib


class TabCharacter(obnamlib.ObnamError):

    msg = 'TAB character found: {line}'


class LongLine(obnamlib.ObnamError):

    msg = 'long line ({length} chars after TAB expansion): {line}'


class SourceCodeNitpicker(cliapp.Application):

    max_line_length = 79

    def setup(self):
        self.errors = False

    def cleanup(self):
        if self.errors:
            sys.exit(1)

    def process_input_line(self, filename, line):
        line = line.rstrip('\n')

        self.check_for_tabs(filename, line)
        self.check_for_long_line (filename, line)

    def check_for_tabs(self, filename, line):
        if not filename.endswith('Makefile'):
            if '\t' in line:
                self.error(filename, self.lineno, TabCharacter(line=line))

    def check_for_long_line(self, filename, line):
        expanded = line.expandtabs()
        if self.line_is_long(expanded) and self.line_can_be_broken(line):
            self.error(
                filename, self.lineno,
                LongLine(line=line, length=len(expanded)))

    def line_is_long(self, line):
        return len(line) > self.max_line_length

    def line_can_be_broken(self, line):
        return len(line.split()) > 1

    def error(self, filename, lineno, error):
        self.output.write(
            '%s:%s: %s\n' % (filename, lineno, str(error)))
        self.errors = True


SourceCodeNitpicker().run()