I wanted to start a new git repository containing just the history of two specific files from my help-scraper repository.
\nI started out planning to use git filter-branch for this, but got put off when this StackOverflow thread started talking about the need to understand the differences between macOS sed and regular GNU sed.
That thread also pointed me to git-filter-repo, a really neat Python script that makes this so much easier.
\ngit-filter-repo is written in Python but has zero dependencies on anything else - all you need to do is place the script somewhere on your path.
I ran echo $PATH to check which directories were on my path - one of them is .local/bin - so I decided to put it there:
cd ~/.local/bin\nwget https://raw.githubusercontent.com/newren/git-filter-repo/main/git-filter-repo\nchmod 755 git-filter-repo\nIt didn't work until I ran chmod 755 on it.
Now I can run this:
\n% git filter-repo\nNo arguments specified.\nConfirming the new command is installed!
\nThe --path option can be used to preserve just the history of specified paths. I ran this:
cd /tmp\ngit clone https://github.com/simonw/help-scraper\ncd help-scraper\ngit filter-repo --path flyctl/fly.graphql --path github/github.graphql\nThe command output was:
\nParsed 132 commits\nNew history written in 0.33 seconds; now repacking/cleaning...\nRepacking your repo and cleaning out old unneeded objects\nHEAD is now at 828a1efc GitHub: Tue Mar 22 15:09:04 UTC 2022\nEnumerating objects: 144, done.\nCounting objects: 100% (144/144), done.\nDelta compression using up to 12 threads\nCompressing objects: 100% (69/69), done.\nWriting objects: 100% (144/144), done.\nTotal 144 (delta 34), reused 55 (delta 34), pack-reused 0\nCompletely finished after 1.33 seconds.\nAnd sure enough, my repo now only contains those two files:
\n% find . | grep -v .git\n.\n./flyctl\n./flyctl/fly.graphql\nAnd the commit history for those files:
\n% git log --stat --pretty=oneline | head -n 10\n828a1efc4307cca6cd378c394c2d33eac2eceb52 GitHub: Tue Mar 22 15:09:04 UTC 2022\n github/github.graphql | 27 +++++++++++++++++++++++++++\n 1 file changed, 27 insertions(+)\n44fc9ebb49a255ad1c90f7761ab2ab1267135ff9 GitHub: Fri Mar 18 15:08:38 UTC 2022\n github/github.graphql | 1 +\n 1 file changed, 1 insertion(+)\ndae52d5b94761145333867bc6641e8210409c3b7 GitHub: Thu Mar 17 16:58:45 UTC 2022\n github/github.graphql | 3 +++\n 1 file changed, 3 insertions(+)\n33e0691bc579bb1e26ea6d05556cf047f5c120da GitHub: Wed Mar 16 15:05:35 UTC 2022\nhelp-scraper % git log --stat --pretty=oneline | head -n 20\n828a1efc4307cca6cd378c394c2d33eac2eceb52 GitHub: Tue Mar 22 15:09:04 UTC 2022\n github/github.graphql | 27 +++++++++++++++++++++++++++\n 1 file changed, 27 insertions(+)\n44fc9ebb49a255ad1c90f7761ab2ab1267135ff9 GitHub: Fri Mar 18 15:08:38 UTC 2022\n github/github.graphql | 1 +\n 1 file changed, 1 insertion(+)\ndae52d5b94761145333867bc6641e8210409c3b7 GitHub: Thu Mar 17 16:58:45 UTC 2022\n github/github.graphql | 3 +++\n 1 file changed, 3 insertions(+)\n33e0691bc579bb1e26ea6d05556cf047f5c120da GitHub: Wed Mar 16 15:05:35 UTC 2022\n github/github.graphql | 54 ++++++++++++++++++++++++++++++++++++++++++++++++---\n 1 file changed, 51 insertions(+), 3 deletions(-)\n3dae87045436c3a8c6c84409f9e7ec5ae3bfae74 GitHub: Tue Mar 15 15:08:59 UTC 2022\n github/github.graphql | 18 ++++++++++++++++++\n 1 file changed, 18 insertions(+)\n74a3f34c254f789948ee0257981f5d30a094d19f Fly: Tue Mar 15 06:23:03 UTC 2022\n flyctl/fly.graphql | 16 ++++++++++++++++\n 1 file changed, 16 insertions(+)\n63c92c60285b08a898b874b9296b28935f0e7ea8 GitHub: Mon Mar 14 15:09:42 UTC 2022\n github/github.graphql | 5 ++++-\n