git

Version control system.

Tips

Use fetch and merge instead of pull (see).

Commands

git commit --amend edit message of most recent commit.
git branch -m new-name: Rename branch.
git push origin :old-name new-name: Delete the old-name remote branch and push the new-name local branch.
git diff develop master -- . ':(exclude)**/*.test.js': Non-test changes between branches.
git reset HEAD~1: Undo most recent commit.
git add -A: Stage all files (same as -u but also adds untracked files).
git add -u: Stage all tracked files (does all git add and git rm commands).
git diff branch_1..branch_2: Compare branches.
git blame [file]: Show what revision and author last modified each line of a file.
git checkout -: Checkout previous branch.
git checkout [commit-id] [filename]: Restore specific file from specific commit.
git clone: Get a copy from the upstream branch to prime your local repository.
git commit -m "message" to advance the current branch.
git diff [filename]: To see exactly what was modified.
git fetch: Update local cache of remote branch.
git log -- [filename]: Show commit history of a file.
git log -p [filename]: Show change history of a file (i.e. code changes).
git log: Show a log of all commits starting from HEAD back to the initial commit.
git mv [filename1] [filename2]: Rename a file in the repository.
git reflog show: List all local commits.
git reset --hard [commit]: Roll branch back to previous commit permanently erasing all newer commits.
git reset HEAD [file]: Unstage a Staged file.
git revert HEAD: Remove the most recent commit.
git rm -f [filename]: Remove file from the repository.
git stash drop: Delete most recent stashed changes.
git stash pop: Apply stashed changes and remove them from stash.
git stash: Moves uncommitted changes to the stash.
git status: Show which files have changed between the current project state and HEAD.
git mv [filename1] [filename2]: Rename a file in the repository.

Life Cycle of a change

Run git status.
- Possibly run git stash to hide uncommitted changes.
Create Branch: git branch <new_branch> <current_branch>.
Switch to new branch: git checkout <new_branch>.
Make changes...
Run git status.
Stage all changes to tracked files: git add -u (or git add -A to add new files also).
Run git status.
Commit changes: git commit -m "[comment]".
Ensure current branch is up to date: git fetch.
Merge branches; At each stage resolve any conflicts:
1. Switch to the parent branch: git checkout [parent_branch].
2. Ensure branch is up to date: git fetch followed by git merge origin.
3. Switch to the new branch: git checkout [new_branch].
4. Merge parent with new_branch: git merge [parent_branch]. Best to try merging this way first.
5. Switch to the parent branch: git checkout [parent_branch].
6. Merge new_branch with parent_branch: git merge [new_branch].
7. Publish your changes: git push.
Delete new branch: git branch -d [new_branch].

Setup

Use git init: to create a new repository.

Add a .gitignore file to the repositories root directory to exclude files from Git (example).

Configuration file

~/.gitconfig:

[user]                                                                          
    name = Paul Ahern                                                           
    email = ahernp@ahernp.com                                                   
[merge]                                                                         
    tool = vimdiff                                                              
[core]                                                                          
    editor = vi                                                                 
[alias]                                                                         
    co = checkout                                                               
    ci = commit                                                                 
    st = status                                                                 
    br = branch                                                                 
    hist = log --pretty=format:\"%h %ad | %s%d [%an]\" --graph --date=short     
[color]                                                                         
    ui = auto                                                                   
[push]                                                                          
    default = simple                                                            

# Use ssh instead of https                                                      
[url "git@github.com:"]                                                         
    insteadOf = https://github.com/