Adding commits to a repo from another with unrelated commit histories

patches.py

# First do:
# git format-patch $commit_id..HEAD
# edit this script to only include commits that change watchfile*
# *note that commits that include this file AND alter other files will also be included
# then run this script
# then run ./process_patches.py | xargs git am

import os
import sys
watchfile = 'chapters/testing.md'
patchdir = '/home/amorley/git_repos/archiv/becky/the-turing-way-testing'
patchfiles = os.listdir(patchdir)
patchfiles = list(filter(lambda x: x[-5:] == 'patch', patchfiles))
patchestoapply = []
for file in patchfiles:
    with open(patchdir+'/'+file, 'r', encoding='utf8') as f:
        try:
            commit = f.readline().split(' ')[1]
        except:
            continue
        author_info = f.readline()
        author_name = str.join(' ',author_info.split(' ')[1:3])
        author_email = author_info[author_info.index('<')+1:author_info.index('>')]
        date = f.readline()
        subject = f.readline()
        for i,line in enumerate(f):
            if '+++ b/{}'.format(watchfile) in line:
                patchestoapply.append(patchdir+'/'+file)
patchestoapply = sorted(patchestoapply)
for p in patchestoapply:
    print(p)