Oh shit Git

A Guide to Fixing Common Git Mistakes

Common QnA

How to Hard Sync local Master with Original Upstream

Follow these steps in your main branch (upstream" is the original repository and "origin" is the fork one) :

• git checkout main
  git pull upstream main
  git reset --hard upstream/main
  git push origin main --force

Why the previous commits of another branch are showing in the new branch

Let's say you have this repository with branch 'prev_branch'

---o---o---A    prev_branch

Let's say you commit something A in prev_branch and created new branch 'new_branch'1, it won't differ until you start commiting to new branch

---o---o---A    prev_branch + new_branch

Then you commit B in newbranch

---o---o---A      prev_branch
            \
             B    new_branch

The new commit B has A as its parent commit. Now prev_branch and new_branch differ in some way.

---o---o---A---X---Y    prev_branch
            \
             B---Z      new_branch

Summary

When you create a new branch from a particular branch, you'll start from the point where that branch currently is. So all commit history will be there in the new branch as well.
A good rule of thumb is to always create a new branch from the branch that you intend to eventually merge the new branch into (main branch). So if D is intended to be merged into main at some future point in time, create it from the current tip of main.

For more details refer blog / blog

Follow this while creating new branch and commiting changes:

- git checkout main/master
- git branch -b new_branch
- git add .
- git commit -m "message"

Edit a commit

1. Convenient way to modify the most recent commit

    # Edit src.js and main.js
    git add src.js
    git commit 
    # Realize you forgot to add the changes from main.js 
    git add main.js 
    git commit --amend --no-edit

2. Using git reset

    git add .
    git commit -m "This commit is a mistake"
    git reset HEAD~
    git add main.js
    git commit -m "This commit corrects the mistake"

3. To undo the last two commits, use the commands:

   git add
   git commit -m "This commit is a mistake"
   # make changes to files
   git add .
   git commit -m "This commit is another mistake"
   # want to go back to 2nd last commit to make changes
   git reset HEAD~2
   # make changes
   git add .
   git commit -m "this commit corrects both mistakes"

   for more info refer this blog

4. Change the last commit message

   # it will change the last commit's message
   git commit --amend -m "New commit message" 

   for more info, watch this video

To Check the commit Tree:

#Run below to visualize the commit tree.
gitk 
git log show commit logs.

Rebase

#Fetch the latest changes
git fetch main
#Rebase onto the upstream branch
git rebase upstream/main`

Good Practice

1. Avoid committing unnecessary files:

   #Avoid using which commits everything.
   git commit -a

2. Use targeted commit commands:

   git add specific file