Git Magic

To pull in changes from just one file on another branch:

git checkout [branch_name] -- [file_path]

The -- relates to the UNIX shell, not Git, where -- means "everything that follows -- is a filename".

To rename an existing local branch. Switch to/checkout that branch and run:

git branch -m new-branch-name
# so, if you want to name a branch 'user-test-fix' the line would be:
git branch -m user-test-fix

To add parts of a file

git add -p <filename>
# so:
git add -p app/Models/Post.php

when git then asks Stage this hunk [y,n,q,a,d,/,j,J,g,s,e,?]? These options are: stage this hunk for the next commit

• n do not stage this hunk for the next commit
• q quit; do not stage this hunk or any of the remaining hunks
• a stage this hunk and all later hunks in the file
• d do not stage this hunk or any of the later hunks in the file
• g select a hunk to go to
• / search for a hunk matching the given regex
• j leave this hunk undecided, see next undecided hunk
• J leave this hunk undecided, see next hunk
• k leave this hunk undecided, see previous undecided hunk
• K leave this hunk undecided, see previous hunk
• s split the current hunk into smaller hunks
• e manually edit the current hunk
  • You can then edit the hunk manually by replacing +/- by #
• ? print hunk help

Get the number of files changed between the current branch and a given branch

git --no-pager diff --shortstat <GIVEN BRANCH NAME>
# so:
git --no-pager diff --shortstat my-feature-branch

How to undo changes from a given commit

To undo the changes to a file from a given commit id, run the following:

git restore --source <commit-id>^ --<path/to/file>

The caret (^) symbol refers to the parent of the specified commit, effectively pointing to the state before the commit.

How to create a branch and switch to it

git checkout -b my-new-feature

This command does two things: it creates the branch "my-new-feature" and switches your working directory to this new branch.

How to make an empty commit

Sometimes it's useful to push an empty commit. You can use the --allow-empty flag for this:

git commit --allow-empty -m "Trigger CI"