Stash, Tags and Useful Commands

Introduction

This lesson collects the everyday tools that make Git pleasant: parking half-finished work, labelling important points in history, and finding out who changed what and why.

Stash: park work for later

Imagine you are halfway through a change when you must switch branches to fix something urgent. Your edits are not ready to commit. Stash puts them on a shelf:

git stash                 # save changes and clean your working folder
git switch main           # do the urgent work
git switch feature
git stash pop             # bring the changes back

Useful variations:

• git stash -u also stashes new, untracked files.
• git stash list shows what is on the shelf.
• git stash apply restores a stash but keeps it on the shelf.
• git stash drop removes one.

Tags: label a moment in history

A tag is a permanent name for a specific commit, often a release.

git tag -a v1.0.0 -m "First release"
git tag                    # list tags
git push origin v1.0.0     # tags are not pushed automatically

Use clear numbers such as semantic versioning: MAJOR.MINOR.PATCH. Increase the patch for bug fixes, the minor number for new features that do not break anything, and the major number for breaking changes.

.gitignore done well

List files that should never be tracked:

node_modules/
.env
*.log
dist/

If a file is already tracked, adding it to .gitignore is not enough. Stop tracking it with git rm --cached file. Never commit secrets such as passwords or keys.

Investigate history

git log --oneline --graph --all      # a map of all branches
git log -p -- notes.txt              # every change to one file
git log --author="Sam" --since="2 weeks ago"
git show a1b2c3d                     # what one commit changed
git diff main..feature               # differences between two branches
git blame notes.txt                  # who last changed each line

git blame is not about blame. It helps you find the commit, and then its message, that explains why a line is the way it is.

Helpful settings

git config --global init.defaultBranch main
git config --global pull.rebase false
git config --global alias.st status

An alias turns git st into git status. Choose settings that match your team's habits.

Try it yourself

In a practice repository, edit a file without committing, stash it, check that the file is clean, then pop the stash. Then tag the latest commit v0.1.0 and list the tags.

Summary

• git stash shelves unfinished work, and pop brings it back.
• Annotated tags mark releases, and tags must be pushed separately.
• log, show, diff and blame help you understand how code got to its current state.