Git - Versus

Last Updated: 2023-01-15

git fetch vs git pull

git pull = git fetch + git merge

• git fetch: remote repo to local repo.
• git merge: local repo to working directory.
• git pull: remote repo to local repo AND working directory.

check if local repo is up to date

$ git fetch --dry-run

git checkout vs git switch

git switch -c <branch name> is equivalent to git checkout -b <branch name>.

To replace two common uses of git checkout: git switch to switch to a new branch after creating it if necessary, and git restore to restore changes from a given commit.

git rebase vs git merge

Both are designed to integrate changes from one branch into another branch.

• git merge feature main will create a new "merge commit" in the feature branch to incorporate chagnes in the main branch.
• git rebase main will move the feature on top of the main branch (incorporating all new commits in the main branch.) Much cleaner project history.

Patch a CL: checkout vs branch vs cherry-pick vs pull

before patch:

local_commit
origin/HEAD

Checkout and create a new branch

$ git fetch foo bar && git checkout -b baz FETCH_HEAD

You will be in a new baz branch

Checkout

$ git fetch foo bar && git checkout FETCH_HEAD

You will be in a HEAD detached at FETCH_HEAD branch (use git checkout -b baz to create a new baz branch)

Cherry-pick

$ git fetch foo bar && git cherry-pick FETCH_HEAD

You will stay in the main branch, check git log:

remote_commit
local_commit
origin/HEAD

Pull and rebase

$ git pull foo bar --rebase

You will stay in the main branch, check git log:

local_commit
remote_commit
origin/HEAD

Pull and merge

$ git pull foo bar --no-rebase (i.e. merge)

You will stay in the main branch, check git log:

merge_commit
local_commit
remote_commit
origin/HEAD

https vs ssh

You can use either https or ssh to connect to remote repo:

• https:
  • https://github.com/foo/bar.git
  • it will ask for your username and password when you try to connect remote repo
• git:
  • [email protected]:foo/bar.git
  • it uses ssh keys to verify you identity.
    • Copy and paste your public key(~/.ssh/id_rsa.pub) to Github account
    • Specify the private key in ~/.ssh/config as

Host heroku.com
HostName heroku.com
IdentityFile /Users/username/.ssh/heroku_key

To check your remote

$ git remote show origin
* remote origin
    Fetch URL: https://github.com/foo/bar.git
    Push  URL: https://github.com/foo/bar.git
    HEAD branch: master