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+# Git
+
+My personal cheat sheet of commands for various tools and workflows
+
+- [Git](#git)
+  - [Split out subfolder into new repository](#split-out-subfolder-into-new-repository)
+    - [(Optional) Migrate original subdir to submodule](#optional-migrate-original-subdir-to-submodule)
+
+## Split out subfolder into new repository
+
+*Be sure you are inside the original repo*
+
+```sh
+cd <orignal_repository>/<subdir-to-split>
+```
+
+Set local variables for use
+
+```sh
+username="$(git config user.username)"
+subdir="$(git rev-parse --show-prefix)"
+newrepo="$(basename $subdir)"
+oldrepo="$(git rev-parse --show-toplevel)"
+cd $oldrepo
+```
+
+Create a new branch containing only the sub-directory using `git subtree`
+
+```sh
+git subtree split -P $subdir -b $newrepo
+```
+
+Create a temp git repo and pull in the newly created branch
+
+```sh
+cd $(mktemp -d)
+
+git init && git pull $oldrepo $newrepo
+```
+
+Copy over the git artifacts from original repo's root directory
+
+```sh
+cp -rt ./ $oldrepo/.gitignore $oldrepo/.gitattributes $oldrepo/.vscode
+```
+
+Commit changes
+
+```sh
+git add -A && git commit -m "split out $newrepo into submodule"
+```
+
+Create a new remote repository using something like [gh](https://github.com/cli/cli)
+
+```sh
+gh repo create $username/$newrepo
+```
+
+(Optional) You can also just create the new remote repository manually and set the new local repository's remote with
+
+```sh
+git remote add origin https://github.com/$username/$newrepo
+```
+
+Push newly created repository to remote
+
+```sh
+git push -u origin master
+```
+
+### (Optional) Migrate original subdir to submodule
+
+Switch back into the original repository
+
+```sh
+cd $oldrepo
+```
+
+Remove the `subdir` from git and the filesystem
+
+```sh
+git rm -rf $subdir
+rm -rf $subdir
+```
+
+Add the newly created remote repository as a submodule at the `subdir`'s path
+
+```sh
+git submodule add git@github.com:$username/$newrepo $subdir
+git submodule update --init --recursive
+```
+
+Commit the changes to the original repository and push to remote
+
+```sh
+git commit -m "split out $newrepo into submodule"
+git push -u origin master
+```
+