Resolve conflicted areas of a file in favor of theirs or ours and leave correctly merged areas as is

git_resolve.py

# This is an automation of https://stackoverflow.com/questions/71783590/git-merge-strategy-option-theirs-for-individual-files
# Example:
#  git_resolve.py --theirs path/to/some/file

import os
import argparse
from shutil import copyfile
import subprocess

parser = argparse.ArgumentParser(description='Resolve conflicted areas of a file during a git merge')
parser.add_argument('path', type=str, help='Path of the file for which to resolve merge conflict')
parser.add_argument('--theirs', action='store_true', help='Use their version wherever there is a conflict')
parser.add_argument('--ours', action='store_true', help='Use our version wherever there is a conflict')

args = parser.parse_args()

def run(cmd, outfilename=None):
    if outfilename is not None:
        with open(outfilename, "w") as outfile:
            subprocess.run(cmd, stdout=outfile)
    else:
        subprocess.run(cmd)

def main(args):
    if args.theirs and args.ours:
        print("Error! You must chose either --theirs or --ours but not both")
        exit(1)
    elif args.theirs:
        which_one = "--theirs"
    elif args.ours:
        which_one = "--ours"
    else:
        print("Error! You must chose one of --theirs or --ours")
        exit(1)

    run(["git", "show", f":1:{args.path}"],  f"{args.path}.base")
    run(["git", "show", f":2:{args.path}"],  f"{args.path}.ours")
    run(["git", "show", f":3:{args.path}"],  f"{args.path}.theirs")

    run(["git", "merge-file", which_one, f"{args.path}.ours", f"{args.path}.base", f"{args.path}.theirs"])
    copyfile(f"{args.path}.ours", f"{args.path}")
    os.remove(f"{args.path}.base")
    os.remove(f"{args.path}.base")
    os.remove(f"{args.path}.theirs")

main(parser.parse_args())