Cheet sheet to handle with Git in everyday development

Basic Flows

Create Repository

Create a remote branch in Github before you push a new repository from local

// initialize
mkdir <my_project>
cd <my_project>
git init
git remote add origin <remote_repository_URL>

// after addition or modification of files
git add <file_name>
git commit -m "<commit_message>"
git push -u origin main

Team Development

// create branch
git checkout <parent_branch>
git pull <parent_branch>
git checkout -b <feature_branch>

// modifiy file as you need
git add .
git commit -m "<commit_message>"
git push -u origin <feature_branch>

// (optional)
// in the case your branch got outdated and you can't merge in the develop
git rebase <parent_branch>
git push -f

// after modification
git checkout <parent_branch>


// (optional)
// you would do this in GitHub
git merge <feature_branch>
git push origin --delete <feature_branch>

// after merge
// clean up local branch
git branch -d <feature_branch>

Frequent modifications

Change branch name

git branch -m <old_branch_name> <new_branch_name>

Amend commit message

// Current commit
git commit --amend

// Past commit
// Change status pick -> reword
// Then automatically open commit message editor
git rebase -i HEAD~n // amend n commits from latest
git rebase -i <commit_id> // start ammend from latest to <commit_id>

Trouble shooting

Back to specific commit

// move to specific commit
// cannot reflect your modification (detached HEAD)
git checkout <commit_id> 

Stash Change

git stash list // show all stash list
git stash show -p stash@{n} // show nth stash detail
git stash push "<stash_message>" // save changes to stash
git stash apply stash@{n} // apply nth stash
git stash drop stash@{n} // delete nth stash
git stash clear // clean up all stash

Conflict

Commonly usable among branch or stash

• Roll back without resolving conflicts

git restore --source=HEAD --staged --worktree .
git merge --abort // merge
git rebase --abort // rebase

• Resolve conflicts

git status
// Edit conflicted files
git add <conflicted-file>
git commit

Commit History Management

• To modify commit detail

// for resent commits
// role back nth commit reference before
git reset --mixed HEAD~n // changes unstaged
// edit changes
git push

// for far past commits
git rebase -i
// change `pick` to `edit` for target commits
git rebase --continue
// edit files
// need -f option to push
git push -f

• To delete commit

// permanently delete local change and write over by remote branch
git fetch origin
git reset --hard origin

// pick multiple commits to delete
git rebase -i HEAD~{n}
// change `pick` to `drop` for target commits
git rebase --continue
// need -f option to push
git push -f

Recovery

• Backup Branch

// create backup_branch
git checkout <feature_branch>
git checkout -b backup_<feature_branch>

// work on feature_branch
git checkout <feature_branch>
// failture something like rebase or reset --hard

// recovery from backup_branch
git reset --hard backup_<feature_branch>
git push -f

• Last resort
  Avoid messing up anymore before searching by reflog

// Find
git reflog
// get commit id to roll back
git reset --hard <commit id>

Detail Differences

Staging

git add .  // All of the modification
git add <file_name>  // Specific files

Push

git push -u origin <feature_branch> // First time. Set the link between remote and local
git push <feature_branch> // May omit -u option after setting tracking branch

Pull

git fetch // Update remote tracking branch. Not merge to local branch.
git pull // Update local current branch
git pull <branch_name> // Update specific local branch

Reset

git reset --soft HEAD~n // changes on staging
git reset --mixed HEAD~n // changes unstaged
git reset --hard <commit_id> // changes deleted

Research

• Branch

git branch // show all local branch
git status // show staging status in current branch

*Reference History

git reflog

• Commit History

git log // show commit log
git log --oneline // in one liner
git log --author=<author_name> // someone specific
git log --since="yyyy-mm-dd" --until="yyyy-mm-dd" // in specific term
git show <commit_id> //Detail of a specific commit
git blame <file_path> // show who edit the line

• File Difference

git diff // all
git diff <file_name> // specific file
git diff <commit_id> <file_name> // between specific commit and working tree
git diff <commit_id_1> <commit_id_2> // between specific commits