Warning: This project is experimental and may even be a really bad idea!
A history-preserving file splitter for Git.
You create a config file indicating how you'd like to split a file, and
git-split will perform the Git operations to split that file and perform
edits to the resulting files to include just the parts you specified, all while
maintaining the git blame history.
Sometimes a module starts out simple, but grows to the point where it would be better if it were divided into two (or many!) modules instead. It is easy to copy and paste the appropriate parts of a file into new files, but that usually results in the loss of the valuable line-by-line history that Git maintains.
You can preserve the history with the right combination of branching, moving, editing, committing and merging, but it can be tedious and fiddly. Furthermore, it requires that you delete all of the text that you don't want in the newly split-off file, which becomes onerous if you've got a large source file that you want to split into several files. You end up deleting the same blocks of text over and over again.
Using this utility, you create a TOML-formatted config file specifying the source file to start with, the resulting files to split to, and which lines from the source file you want to include in each split out file. After running the utility, you'll end up with the files as specified, committed into the currently checked out Git branch.
Start with an unmodified working tree. git-split will abort otherwise. "Please, commit your changes or stash them before running git-split."
The split will be a merge into your current branch. You may want to create and checkout a branch for that specifically.
# If poetry isn't installed
python3 -m pip install --user pipx
python3 -m pipx ensurepath
pipx install poetry
# Install dependencies
poetry install
# Setup pre-commit and pre-push hooks
poetry run pre-commit install -t pre-commit
poetry run pre-commit install -t pre-push
# To run pre-commit hooks manually (without a commit)
poetry run pre-commit run --all-files