Introduction

In this blog we have covered several advanced features of git, all the while unfurling the Marvel universe story

git commit --amend # (Scenario A and B)
git pull --ff # (Scenario A)
git push remote branch --force-with-lease # (Scenario B)
git diff # (Scenario C)
git rebase -i commit-hash # (squash and reword disussed in Scenario D)
git reset --hard commit-hash # (Scenario E)
git rebase # (Scenario F)
git revert  # (Scenario G)
git switch feature && git rebase main
git merge --no-ff
git tag ( git tag marvel-phase-end) # (Scenario H)
# Bonus: How are Pull Requests in public repo

Setting the Context to the Marvel Story

fun-marvel-git-tutorial: > This is a Marvel-inspired fun Git Tutorial to help a coder transition from a beginner to an advanced Git User

Note

If you would like to review the history discussed in this blog, refer to the below repo: Repo: https://github.com/senthilkumarm1901/fun-marvel-git-tutorial

Instead of a regular tutorial that explains the git commands one by one, this blog takes up an applied approach by weaving the knowledge of git commands in the most practical manner possible - as part of a story of collaboration in Git. I have attempted to keep this as close to real life experience as possible,

Story - A Team of Script Writers at Marvel Enterprises:

A Team of 4 Writers are collaborating in Git to create amazing comic stories in the Marvel Universe

About the Team - A Lead Script Writer at Marvel is tasked with creation of several comics. - He delegates the work to 3 writers with the following responsibilities

Responsibilities

[!IMPORTANT] - Where do all Writers Collaborate - In GitHub
- Each Writer can create a branch for them to commit their efforts
- Upon completion of the work, they are expected to seek Pull Request Review for merging their branch with main where the Lead Script Writer comments and approves.

Lead Script Writer’s Initial Efforts

Create a repo in remote. git clone locally
Push all initial ground work such as
- the context portions in README.md and
- the initial empty version of marvel_heroes.md
The writers are expected to contribute their efforts in their branches in the file marvel_heroes.md

[!NOTE] - The only file all writers are collaborating in is marvel_heroes.md

The Lead Script Writer’s Git Journey

The Boilerplate Git Commands

# Ensuring my Personal GitHub Creds are utilized
% git clone git@github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git

% cd fun-marvel-git-tutorial.git

% git config user.email "senthilkumar.m1901@gmail.com"

% git config user.name "senthilkumarm1901" 

#---

# Ensuring this git_commands file and folder are ignored by git
## will ignore all `git_commands.md` file anywhere in the git repo
% echo "git_commands.md" >> .gitignore
## Ignoring `git_commands/` folder anywhere in the git repo 
% echo "**git_commands/" >> .gitignore

#---

# Now, the LeadWriter made a minor edit

# adding `README.md` and `marvel_heroes.md` files to git
% git add README.md  && git commit -m "LeadWriter: set up the repo and lay the rules"
% git add marvel_heroes.md && git commit -m "LeadWriter: Initial marvel_heroes.md file"

% cat marvel_heroes.md
> In this document, all writers contribute their efforts

% git push origin main

#---

Scenario A: `git commit --amend && git pull --ff && git push remote branch`

# LeadWriter made some minor edits to `README.md`
% vi README.md
## added the changes to previous commit

% git add README.md 
% git commit --amend --no-edit

## It seems after pushing amending commit results in conflicts

% git push origin main
To github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git
 ! [rejected]        main -> main (non-fast-forward)
error: failed to push some refs to 'github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

## Adhereing to the suggestion above
% git pull --ff
Merge made by the 'ort' strategy.

% git push origin main
Enumerating objects: 8, done.
Counting objects: 100% (7/7), done.
Delta compression using up to 8 threads
Compressing objects: 100% (4/4), done.
Writing objects: 100% (4/4), 532 bytes | 532.00 KiB/s, done.
Total 4 (delta 2), reused 0 (delta 0), pack-reused 0
remote: Resolving deltas: 100% (2/2), completed with 1 local object.
To github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git
   619a879..1aac0d4  main -> main

What just happened?

After first git push but before git commit --ammend --no-edit
Both main and origin/main are in the same commit C

A---B---C (main & origin/main)

After git commit --amend, the local and remote main branches have diverged

A---B---C (origin/main)
         \
          C' (main)

After git pull , a 3-way merge happened

A---B---C--- M (main, origin/main)
         \  /
          C'

What is ORT Strategy

The ‘ort’ strategy refers to the “Optimized Recursive Three-Way Merge” strategy
A merge commit was created, combining the remote branch and your amended commit.

Before ORT merge

After ORT merge

[!NOTE] git pull --ff allows Git to fast-forward if possible, but if the branches have diverged (as in your case), Git falls back to performing a merge.

If I wish to avoid a merge-commit in the history, I could have done, git push --force (see another example below)

Scenario B: `git push --force-with-lease`

Image Source

Goal: How about keeping the commit history clean? No, merge commit like above in the 3-way merge.

What if I used git push --force-with-lease

% git add README.md 
% git commit --amend
# EDITED MESSAGE:  `LeadWriter: make more changes to README.md formatting`
% git log --oneline --all
efd7d36 (HEAD -> main) LeadWriter: make more changes to README.md formatting
1aac0d4 (origin/main, origin/HEAD) Merge branch 'main' of github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit


% git push origin main --force-with-lease
Enumerating objects: 7, done.
Counting objects: 100% (7/7), done.
Delta compression using up to 8 threads
Compressing objects: 100% (3/3), done.
Writing objects: 100% (3/3), 405 bytes | 405.00 KiB/s, done.
Total 3 (delta 1), reused 0 (delta 0), pack-reused 0
remote: Resolving deltas: 100% (1/1), completed with 1 local object.
To github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git
 + 1aac0d4...efd7d36 main -> main (forced update)

After git push --force-with-lease update

Unfamiliar with above gitk view, here is the terminal view of the same:

 % git log --oneline --all --decorate --graph
*   efd7d36 (HEAD -> main, origin/main, origin/HEAD) LeadWriter: make more changes to README.md formatting
|\  
| * 619a879 LeadWriter: Initial marvel_heroes.md file
* | b54c24a LeadWriter: Initial marvel_heroes.md file
|/  
* 8664973 LeadWriter: set up the repo and lay the rules
* aa08cbe Initial commit

What just happened?

Before git commit --amend

A---B---C---M (origin/main, main)

After git commit --amend

A---B---C---M (origin/main)
              \
               M' (main)

After git push origin main --force-with-lease

A---B---C---M' (origin/main, main)

A Quick Recap of Force Push

Scenario Recap:

I pushed a commit to the remote repository.
I made additional changes to the same commit (e.g., using git commit --amend).
I am now trying to sync my updated local branch with the remote branch.

Pros and Cons of Using git push --force in This Case

Aspect	Using `git pull --ff` (git pull==`git fetch && git merge`)	Using `git push --force`
Safety	Ensures you’re up-to-date with remote history.	Can overwrite remote history if not careful.
Ease of Use	Requires resolving conflicts if history diverges.	Directly applies your local changes to remote.
Collaboration	Safe for shared branches.	Risky in shared branches (disrupts others).
Commit History	Preserves history integrity.	Rewrites history (can confuse others).

Safer Alternative:
git push --force-with-lease (compared to git push --force) If I must force push, I could try --force-with-lease:

git push origin <branch-name> --force-with-lease

This ensures the remote branch hasn’t been updated by someone else since my last fetch. If there’s a mismatch, Git will reject the push, preventing accidental overwrites.

Note

git push –force vs –force-with-lease discussion in slackoverflow

Cleaner Commit history in Remote Repo because of git push --force-with-lease

Warning

In general, it is better to use git commit --amend (or even git rebase -i commit-hash - discussed in next section) BEFORE you have pushed your changes to remote branch.
But if you have pushed your changes to remote, you must be prepared to use git push --force-with-lease or git push --force-if-includes

Writer1’s Git Journey

The Boilerplate Git Commands

# Writer1 clone the repo
# ensure he uses the right user.email and user.name

% git clone  github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git
% cd fun-marvel-git-tutorial
% git config user.email "senthilkumar.m1901@gmail.com" && git config user.name "senthilkumarm1901"

% git status
On branch main
Your branch is up to date with 'origin/main'.

nothing to commit, working tree clean

# Switch to a new branch `writer1/avengers`
% git switch -c writer1/avengers

Writer 1 making the first commit Writer1: about main 3 avengers

% vi marvel_heroes.md
% git add marvel_heroes.md && git commit -m "Writer1: about main 3 avengers"

% cat marvel_heroes.md
> In this document, all writers contribute their efforts

## About the Main Avengers
- **Iron Man:** Created the Iron Man suit and saved himself from captivity.
- **Captain America:** Led the charge against Hydra during WWII and became a symbol of hope.
- **Thor:** Defended Asgard and Earth, wielding Mjolnir with unshakable valor.

Scenario C - Understanding `git diff --staged` usage

Writer1 making second commit - Writer1: about other 3 avengers

% vi marvel_heroes.md
% git add marvel_heroes.md 
%  git diff --staged
diff --git a/marvel_heroes.md b/marvel_heroes.md
index daf9bed..bacf14a 100644
--- a/marvel_heroes.md
+++ b/marvel_heroes.md
@@ -5,3 +5,7 @@
 - **Captain America:** Led the charge against Hydra during WWII and became a symbol of hope.
 - **Thor:** Defended Asgard and Earth, wielding Mjolnir with unshakable valor.
 
+## Other Main Avengers
+- **Hulk:** Balanced a life of science with his uncontrollable strength to smash enemies.
+- **Hawkeye:** The marksman with unerring aim, standing tall against gods and monsters armed with nothing but a bow and arrow.
+- **Black Widow:** The spy turned Avenger, weaving through shadows with unmatched skill and unwavering loyalty.
\ No newline at end of file
%

Interpretting git diff --staged command

The green lines are the newly created lines in marvel_heroes.md

% git commit -m "Writer1: about other 3 avengers"

Writer 1 making 3rd and 4th commits Writer2: add deadpool to avengers and Writer2: deadpool fighting villains

% git add marevel_heroes.md && git diff --staged

If you see above, a new line is added after Black Widow line and a new section on DeadPool was added

% git commit -m "Writer2: add deadpool to avengers"
% vi marvel_heroes.md 
% git add marvel_heroes.md && git commit -m "Writer2: deadpool fighting villains"

# review the logs
% git log --oneline --all

35f4935 (HEAD -> writer1/avengers) Writer2: deadpool fighting villains
32ed5cc Writer2: add deadpool to avengers
bd1338c Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 (origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

Scenario D - Altering history and commit messages using interactive git rebase

# Since the commit is not pushed to remote yet, 
# the commit messages can be edited,
# even the commits can be squished
% git rebase -i HEAD~2

I am rewording the incorrect commit message from Writer2 to Writer1 I am squashing the newer commit to the previous commit

%  git log --oneline --all
f7bd564 (HEAD -> writer1/avengers) Writer1: add deadpool to avengers
bd1338c Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 (origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

% git push -u origin writer1/avengers

What just happened?

Before git rebase -i HEAD~2

A---B---C---M (origin/main, origin/HEAD, main)
            \
             D---E---F--G (HEAD -> writer1/avengers)

D (d712258): "Writer1: about main 3 avengers."
E (bd1338c): "Writer1: about other 3 avengers."
F (32ed5cc): "Writer2: add deadpool to avengers."
G (35f4935): "Writer2: deadpool fighting villains."

After the following git rebase -i HEAD~2

% git rebase -i HEAD~2
# in another window, you make the following changes
# reword 32ed5cc (F) Writer2: add deadpool to avengers --> `Writer1: add deadpool to avengers`
# squash 35f4935 (G) Writer2: deadpool fighting villains --> Squash it to the previous commit F

A---B---C---M (origin/main, origin/HEAD, main)
            \
             D---E---(F+G) (HEAD -> writer1/avengers)


A---B---C---M (origin/main, origin/HEAD, main)
            \
             D---E---H (HEAD -> writer1/avengers)

After git push --force-with-lease

A---B---C---M (origin/main, main)
            \
             D---E---H (HEAD --> origin/writer1/avengers, writer1/avengers)

Scenario E - Usage of `git reset --hard commit-to-go-to`

LeadWriter is unhappy with Writer1 including DeadPool as an avenger

Writer1 working on removing Deadpool commit entirely:

Simplest but most unsafe solution is git reset --hard but in our case it is okay since we do not want the deadpool commit entirely

# find the commit to reset the git pointer to
% git log --oneline --all
f7bd564 (HEAD -> writer1/avengers, origin/writer1/avengers) Writer1: add deadpool to avengers
bd1338c Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 (origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

# the commit to make the HEAD go back to is `bd1338c`
% git reset --hard bd1338c
HEAD is now at bd1338c Writer1: about other 3 avengers
 

%  git log --oneline --all
f7bd564 (origin/writer1/avengers) Writer1: add deadpool to avengers
bd1338c (HEAD -> writer1/avengers) Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 (origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

# we still need to push this to main branch
# We have already discussed the benefits of `git push --force-with-lease`

% git push origin writer1/avengers --force-with-lease
Total 0 (delta 0), reused 0 (delta 0), pack-reused 0
To github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git
 + f7bd564...bd1338c writer1/avengers -> writer1/avengers (forced update)

What just happened?

Before git reset --hard E

A---B---C---M (origin/main, main)
            \
             D---E---H (origin/writer1/avengers, writer1/avengers)

H - It is the deadpool commit

After git reset --hard E in local

A---B---C---M (origin/main, main)
            \
             D---E (HEAD -> writer1/avengers)
                  \
                   H (origin/writer1/avengers)

After git push origin writer1/avengers --force-with-lease

A---B---C---M (origin/main, main)
            \
             D---E (HEAD -> writer1/avengers, origin/writer1/avengers)

The commit F is permanently removed

Merge Request can be Approved in Remote ir via CLI - Merge (simple fast forward) :

% git log --oneline --all
bd1338c (HEAD -> writer1/avengers, origin/writer1/avengers) Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 (origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

% git rebase main
Current branch writer1/avengers is up to date.

% git switch main
Switched to branch 'main'
Your branch is up to date with 'origin/main'.
 

% git merge writer1/avengers 
Updating efd7d36..bd1338c
Fast-forward
 marvel_heroes.md | 10 ++++++++++
 1 file changed, 10 insertions(+)


% git log --oneline --all
bd1338c (HEAD -> main, origin/writer1/avengers, origin/main, origin/HEAD, writer1/avengers) Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

Writer2’s Git Journey

Boilerplate Git Commands

Writer2 had forked from Lead Script Writer’s commit

# in `Writer2's terminal`
 % git log --oneline --all
efd7d36 (HEAD -> writer2/other_marvel_heroes, origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

% git status
On branch writer2/other_marvel_heroes
nothing to commit, working tree clean

# add about `other marvel heroes` like Black Panther, Captain Marvel and Ant-Man
% vi marve_heroes.md

% git add marvel_heroes.md && git commit -m "Writer 2: add other marvel heroes stories"

% git push -u origin writer2/other_marvel_heroes

Scenario F - Rebase with main

Raise a PR for merging writer2/other_marvel_heroes with main

The PR shows that there are conflicts

Let us 1) rebase main, 2) resolve conflicts, 3) ff the main branch and 4) merge with writer2

# before rebasing
A---B---C (master)
     \
      D---E (feature)

# while on feature branch
# `git rebase master`

A---B---C (master)
         \
          D'---E' (feature)

# now, the `feature` branch can be merged with `master` with a easier `Fast Forward` method

% git fetch origin main  

remote: Enumerating objects: 8, done.
remote: Counting objects: 100% (8/8), done.
remote: Compressing objects: 100% (6/6), done.
remote: Total 6 (delta 1), reused 4 (delta 0), pack-reused 0 (from 0)
Unpacking objects: 100% (6/6), 964 bytes | 56.00 KiB/s, done.
From github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial
 * branch            main       -> FETCH_HEAD
   efd7d36..bd1338c  main       -> origin/main

% git log --oneline --all
7adc2fc (HEAD -> writer2/other_marvel_heroes, origin/writer2/other_marvel_heroes) Writer 2: add other marvel heroes stories
bd1338c (origin/main, origin/HEAD) Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 (main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

% git switch main
Switched to branch 'main'
Your branch is behind 'origin/main' by 2 commits, and can be fast-forwarded.
  (use "git pull" to update your local branch)

% git pull origin main
From github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial
 * branch            main       -> FETCH_HEAD
Updating efd7d36..bd1338c
Fast-forward
 marvel_heroes.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

% git switch writer2/other_marvel_heroes 
Switched to branch 'writer2/other_marvel_heroes'
Your branch is up to date with 'origin/writer2/other_marvel_heroes'.

# 1) rebase main
 % git rebase main
Auto-merging marvel_heroes.md
CONFLICT (content): Merge conflict in marvel_heroes.md
error: could not apply 7adc2fc... Writer 2: add other marvel heroes stories
hint: Resolve all conflicts manually, mark them as resolved with
hint: "git add/rm <conflicted_files>", then run "git rebase --continue".
hint: You can instead skip this commit: run "git rebase --skip".
hint: To abort and get back to the state before "git rebase", run "git rebase --abort".
Could not apply 7adc2fc... Writer 2: add other marvel heroes stories

# 2) resolve conflicts
% vi marvel_heroes.md

% git add marvel_heroes.md && git commit -m "Writer2: resolved conflicts in main rebased under writer2 branch"
[detached HEAD 66c7916] Writer2: resolved conflicts in main rebased under writer2 branch
 1 file changed, 7 insertions(+), 1 deletion(-)

% git rebase --continue
Successfully rebased and updated refs/heads/writer2/other_marvel_heroes.

% git log --oneline --all
66c7916 (HEAD -> writer2/other_marvel_heroes) Writer2: resolved conflicts in main rebased under writer2 branch
7adc2fc (origin/writer2/other_marvel_heroes) Writer 2: add other marvel heroes stories
bd1338c (origin/main, origin/HEAD, main) Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

# 3) switch to main
% git switch main

% git merge writer2/other_marvel_heroes --ff-only
Updating bd1338c..66c7916
Fast-forward
 marvel_heroes.md | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)


% git log --oneline --all
66c7916 (HEAD -> main, writer2/other_marvel_heroes) Writer2: resolved conflicts in main rebased under writer2 branch
7adc2fc (origin/writer2/other_marvel_heroes) Writer 2: add other marvel heroes stories
bd1338c (origin/main, origin/HEAD) Writer1: about other 3 avengers
d712258 Writer1: about main 3 avengers
efd7d36 LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit


# local and remote `writer2` branches have diverged
# but main branch is pushed properly


# since `writer2/other_marvel_heroes` is rebased and `origin/writer2/other_marvel_heroes` is not, 
# we need to force push (but we are doing `safely` with `--force-with-lease`)
% git push --all --force-with-lease
Total 0 (delta 0), reused 0 (delta 0), pack-reused 0
To github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial.git
 + 7adc2fc...66c7916 writer2/other_marvel_heroes -> writer2/other_marvel_heroes (forced update)

What just happened?

The following is the flow when the following is done
- git pull origin main
- git push -u origin writer2/other_marvel_heroes
Note, git rebase is not done

A---B---C---M (HEAD -> main, origin/main, origin/HEAD)
         \
          D (HEAD -> writer2/other_marvel_heroes, origin/writer2/other_marvel_heroes)

Now,
- git checkout writer2/other_marvel_heroes && git rebase main
- push the local changes to remote
- git push -u origin writer2/other_marvel_heroes --force-with-lease

A---B---C---M (main, origin/main, origin/HEAD)
            \
             D' (HEAD -> writer2/other_marvel_heroes, origin/writer2/other_marvel_heroes)


D becomes D' after resolving conflicts

Now,
- git checkout main && git merge writer2/other_marvel_heroes --ff-only

A---B---C---M---D' (HEAD -> main, writer2/other_marvel_heroes, origin/main, origin/writer2/other_marvel_heroes, origin/HEAD)

Writer3’s Git Journey

Boilerplate Git Commands

% git status
On branch writer3/end_game
nothing to commit, working tree clean

% git log --oneline --all
efd7d36 (HEAD -> writer3/end_game, origin/main, origin/HEAD, main) LeadWriter: make more changes to README.md formatting
b54c24a LeadWriter: Initial marvel_heroes.md file
619a879 LeadWriter: Initial marvel_heroes.md file
8664973 LeadWriter: set up the repo and lay the rules
aa08cbe Initial commit

% vi marvel_heroes.md

% git add marvel_heroes.md && git commit -m "Writer3: add endgame story"
[writer3/end_game a79640b] Writer3: add endgame story
 1 file changed, 8 insertions(+)


# added a scene about Eternals watching the Thanos Snap reversed
% vi marvel_heroes.md
% git add marvel_heroes.md && git commit -m "Writer3: Eternals post credit to Endgame"

Scenario G - Reverting to `End Game` commit (before `Eternals` commit)

Raise a PR for merging writer3/end_game with main

% git fetch origin main
remote: Enumerating objects: 11, done.
remote: Counting objects: 100% (11/11), done.
remote: Compressing objects: 100% (8/8), done.
remote: Total 9 (delta 2), reused 7 (delta 1), pack-reused 0 (from 0)
Unpacking objects: 100% (9/9), 1.45 KiB | 64.00 KiB/s, done.
From github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial
 * branch            main       -> FETCH_HEAD
   efd7d36..66c7916  main       -> origin/main


% git log --oneline --all --decorate --graph
* 3d07b3a (HEAD -> writer3/end_game, origin/writer3/end_game) Writer3: Eternals post credit to Endgame
* a79640b Writer3: add endgame story
| * 66c7916 (origin/writer2/other_marvel_heroes, origin/main, origin/HEAD, main) Writer2: resolved conflicts in main rebased under writer2 branch
| * bd1338c (origin/writer1/avengers) Writer1: about other 3 avengers
| * d712258 Writer1: about main 3 avengers
|/  
*   efd7d36 LeadWriter: make more changes to README.md formatting
|\  
| * 619a879 LeadWriter: Initial marvel_heroes.md file
* | b54c24a LeadWriter: Initial marvel_heroes.md file
|/  
* 8664973 LeadWriter: set up the repo and lay the rules
* aa08cbe Initial commit

# go to the endgame commit 
% git revert a79640b
Auto-merging marvel_heroes.md
CONFLICT (content): Merge conflict in marvel_heroes.md
error: could not revert a79640b... Writer3: add endgame story
hint: After resolving the conflicts, mark them with
hint: "git add/rm <pathspec>", then run
hint: "git revert --continue".
hint: You can instead skip this commit with "git revert --skip".
hint: To abort and get back to the state before "git revert",
hint: run "git revert --abort".

Resolving conflicts

% git switch main
% git status
On branch main
Your branch is behind 'origin/main' by 3 commits, and can be fast-forwarded.
  (use "git pull" to update your local branch)

nothing to commit, working tree clean

% git pull
From github.com-personal:senthilkumarm1901/fun-marvel-git-tutorial
 * [new branch]      writer1/avengers            -> origin/writer1/avengers
 * [new branch]      writer2/other_marvel_heroes -> origin/writer2/other_marvel_heroes
Updating efd7d36..66c7916
Fast-forward
 marvel_heroes.md | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

% git merge writer3/end_game 
Auto-merging marvel_heroes.md
CONFLICT (content): Merge conflict in marvel_heroes.md
Automatic merge failed; fix conflicts and then commit the result.

Auto-merging marvel_heroes.md
CONFLICT (content): Merge conflict in marvel_heroes.md
Automatic merge failed; fix conflicts and then commit the result.
% git status
On branch main
Your branch is up to date with 'origin/main'.

You have unmerged paths.
  (fix conflicts and run "git commit")
  (use "git merge --abort" to abort the merge)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
    both modified:   marvel_heroes.md

no changes added to commit (use "git add" and/or "git commit -a")

% git add marvel_heroes.md && git commit -m "Writer3: Merged conflicts"
[main 43ccb28] Writer3: Merged conflicts

% git push -u origin main

What just happened?

Before Reverting

A---B--C--M--D' (main, origin/main, origin/HEAD)
        \
         G---H--I (writer3/end_game, origin/writer3/end_game)

H - Endgame commit
I - Eternals commit

After Reverting where I lose the Eternals commit and go back to H (after resolving conflicts)

A---B--C--M--D' (main, origin/main, origin/HEAD)
        \
         G---H--I--H' (writer3/end_game, origin/writer3/end_game)

Now,
- git switch main
- git merge writer3/end_game

A---B--C--M--D' --- M2 (HEAD --> main, origin/main, origin/HEAD)
        \           /  
         G---H--I--H' (writer3/end_game, origin/writer3/end_game)

Scenario H - Tagging in Git

# give a tag to the current commit in main
% git tag End_of_Phase3 

# list the tags
% git tag
End_of_Phase3

# make another tag to the same  commit
% git tag End_of_Phase4 --force 
% git tag                       
End_of_Phase3
End_of_Phase4

# delete one of the older tags
% git tag --delete End_of_Phase3
Deleted tag 'End_of_Phase3' (was 8448312)
% git tag                       
End_of_Phase4

# 
% git push origin tag End_of_Phase4

Note

A tag is a git concept whereas a Release is GitHub higher level concept.

Conclusion - What have we accomplished?

Note

With finally 12 commits in the remote main branch, we have explained many advanced commands of Git

BONUS

Forking a Public Repo and Request for a Pull Request with Original Repo`

Forking a Public Repo and PR from a Forked Repo to the Original Repo
- 1. Fork the Original Public Repo (OPR) and make it F-OPR
- 1. Clone the F-OPR to local (automatically adds the Forked Repo as Origin for Remote)
- 1. Add a remote pointing to the OPR as Original for Remote (git remote add Original https://github.com/OPR/)
- 1. Make changes locally to F-OPR.
- 1. Push to F-OPR (which you have permission to do)
- 1. Raise a PR to allow F-OPR to merge with OPR

OPR: https://github.com/explosion/spaCy
F-OPR: https://github.com/mribbons/spaCy/tree/master
PR Page: https://github.com/explosion/spaCy/pull/13613

mribbons wants to merge 2 commits into explosion:master from mribbons:master - PR Commit Example: https://github.com/explosion/spaCy/pull/13613/commits/228045464b15de57483926228cb5d045b75998b9

Introduction

Setting the Context to the Marvel Story

The Lead Script Writer’s Git Journey

The Boilerplate Git Commands

Scenario A: git commit --amend && git pull --ff && git push remote branch

What just happened?

Scenario B: git push --force-with-lease

What just happened?

Writer1’s Git Journey

The Boilerplate Git Commands

Scenario C - Understanding git diff --staged usage

Scenario D - Altering history and commit messages using interactive git rebase

What just happened?

Scenario E - Usage of git reset --hard commit-to-go-to

What just happened?

Writer2’s Git Journey

Boilerplate Git Commands

Scenario F - Rebase with main

What just happened?

push the local changes to remote

Writer3’s Git Journey

Boilerplate Git Commands

Scenario G - Reverting to End Game commit (before Eternals commit)

What just happened?

Scenario H - Tagging in Git

Conclusion - What have we accomplished?

BONUS

Forking a Public Repo and Request for a Pull Request with Original Repo`

Scenario A: `git commit --amend && git pull --ff && git push remote branch`

Scenario B: `git push --force-with-lease`

Scenario C - Understanding `git diff --staged` usage

Scenario E - Usage of `git reset --hard commit-to-go-to`

Scenario G - Reverting to `End Game` commit (before `Eternals` commit)