====== Git ======

===== Add tag =====

<code shell>git tag TAG</code>

==== Commit a tag ====

<code>git push origin TAG</code>

==== Commit all tags ====

<code>git push origin --tags</code>

Source: [[https://stackoverflow.com/questions/18216991/create-a-tag-in-a-github-repository]]

===== Clone a specific tag =====

<code bash>git clone --depth 1 --branch <tag_name> <repo_url></code>

===== Specify the private SSH-key to use when executing a Git command: =====

<code bash>ssh-agent bash -c 'ssh-add /home/git/.ssh/key-filename; git $GIT_COMMAND'</code>
  
Example:

<code bash>ssh-agent bash -c 'ssh-add /home/git/.ssh/key-filename; git push'</code>

Source: [[https://stackoverflow.com/questions/4565700/how-to-specify-the-private-ssh-key-to-use-when-executing-shell-command-on-git]]

===== Remove submodule =====

0. mv a/submodule a/submodule_tmp

1. git submodule deinit -f -- a/submodule

2. rm -rf .git/modules/a/submodule

3. git rm -f a/submodule # Note: a/submodule (no trailing slash)
==== or, if you want to leave it in your working tree and have done step 0 ====

3. git rm --cached a/submodule

3bis mv a/submodule_tmp a/submodule

Source: [[https://stackoverflow.com/questions/1260748/how-do-i-remove-a-submodule]]

===== git undo all uncommitted or unsaved changes =====

<code>git checkout .</code>

Or:

<code>git checkout [some_dir|file.txt]</code>

Source: [[https://stackoverflow.com/questions/14075581/git-undo-all-uncommitted-or-unsaved-changes]]

===== How to undo local changes to a specific file =====

<code>git checkout -- <file></code>

Source: [[https://stackoverflow.com/questions/31281679/how-to-undo-local-changes-to-a-specific-file]]

===== Undo all uncommitted or unsaved changes =====

Source: [[https://stackoverflow.com/questions/14075581/git-undo-all-uncommitted-or-unsaved-changes]]

===== Getting the difference between two repositories =====

<code>git remote add -f b path/to/repo_b.git
git remote update
git diff master remotes/b/master
git remote rm b</code>

Source: [[https://stackoverflow.com/questions/1968512/getting-the-difference-between-two-repositories]]


===== How do I "commit" changes in a git submodule? =====

So, first commit/push your submodule's changes:

<code>cd path/to/submodule
git add <stuff>
git commit -m "comment"
git push</code>

Then, update your main project to track the updated version of the submodule:

<code>cd /main/project
git add path/to/submodule
git commit -m "updated my submodule"
git push</code>

Source: [[https://stackoverflow.com/questions/5542910/how-do-i-commit-changes-in-a-git-submodule]]

===== Remove sensitive files and their commits from Git history =====

<code>git filter-branch --force --index-filter "git rm -r --cached --ignore-unmatch PATH-TO-YOUR-FILE-WITH-SENSITIVE-DATA" --prune-empty --tag-name-filter cat -- --all
git push --force --verbose --dry-run
git push --force</code>


Source: [[https://stackoverflow.com/questions/872565/remove-sensitive-files-and-their-commits-from-git-history]]

===== How to merge two or multiple git repositories into one =====

  * [[https://medium.com/altcampus/how-to-merge-two-or-multiple-git-repositories-into-one-9f8a5209913f]]
  * [[https://stackoverflow.com/questions/1425892/how-do-you-merge-two-git-repositories]]
  * [[https://github.com/apenwarr/git-subtree]]