dirvimdiff

#!/usr/bin/env python3
""" diff two folders, show diffences per file in a tab """
import os
import sys
import re
import tempfile
import subprocess
import logging
import io
#
# Copyright (C) 2016,
#   Thomas Langewouters <thomas.langewouters@thouters.be>
# Copyright (C) 2022,
#   Thomas Langewouters <thomas.langewouters@thouters.be>
#
# This is free software, you can redistribute it and/or modify it under the
# terms of the GNU General Public License version 2 as published by the Free
# Software Foundation.
#
# KNOWN ISSUES
# This file's quality is 'QUICK HACK'
# - it expects LOCALE/ env LANG to be 'C'
# - parses output of 'diff', will fail if filenames contain 'Only in', ': ', etc
# -

NEWLINE = "\n"
HELP = """\
dirvimdiff - script to show two directories' file differences in vim tabs"
dirvimdiff [options] dir1 dir2"

Option:
-g    Use gvimdiff (graphical mode) instead of vimdiff"
All other options are passed to diff
"""


def main():
    """ main function """
    vimdiff = "vimdiff"
    if sys.argv[1] == "-g":
        vimdiff = "gvimdiff -f"
        del sys.argv[1]

    if "--help" in sys.argv:
        print(HELP)
        sys.exit(1)

    _scriptname = sys.argv.pop(0)
    dir1 = sys.argv.pop(0)
    dir2 = sys.argv.pop(0)

    cmd = f"diff -r {dir1} {dir2} --brief --exclude '*.o' --exclude '*.pdf' --exclude '*.a'"

    with tempfile.NamedTemporaryFile(prefix='dirvimdiff', encoding='utf-8', mode='w') as script, \
            subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE) as proc:
        script.write(":ex\n")
        for line in io.TextIOWrapper(proc.stdout, encoding="utf-8"):
            if line.startswith("Only in"):
                only_in = line[len("Only in "):line.find(
                    ": ")] + "/" + line[line.find(": ")+2:]
                logging.debug("ONLY IN %s", only_in)
                logging.debug("DIR1 %s", dir1)
                logging.debug("DIR2 %s", dir2)
                if only_in.startswith(dir1):
                    files = (only_in, "/dev/null")
                else:
                    files = ("/dev/null", only_in)
            elif line.startswith("Files "):
                files = re.match("Files (.*) and (.*) differ", line).groups()
                logging.debug("DIFFER %s", files)
            else:
                raise Exception(f"unexepcted {line}")

            command = f":tabnew {files[0]}{NEWLINE}:vert diffsplit {files[1]}{NEWLINE}"
            logging.debug("command: %s", command)
            script.write(command)
        script.write(":vi\n")
        script.flush()

        logging.debug("script is %s", script.name)
        command = f"{vimdiff} -s {script.name}"
        if os.path.isfile("commit.txt"):
            command += " commit.txt"
        os.system(command)

if __name__ == "__main__":
    main()