The document provides an extensive guide on using Git, focusing on foundational concepts, common troubleshooting techniques, and recovery methods from catastrophic failures. It outlines key operations such as fixing commit mistakes, cleaning up history with rebase, and using git reflog to recover previous states. Additionally, it includes cheat sheets for fixing commits and useful commands to enhance users' proficiency with Git.

1. “GIT-ING”
OUT OF
TROUBLE
H O W TO G O B A C K I N T I M E W I T H O U T E R A S I N G
Y O U R S E L F F R O M T H E F U T U R E

2. OUTLINE
• Basic Foundations of Git
• Fixes for Common Issues
• Other Useful Commands
• Recovering from
Catastrophic Failures

3. BASIC GIT
FOUNDATIONS
D O E S A N Y O N E R E A L LY G I T G E T ?

4. WHAT IS GIT ANYWAY?
Key-value data store
• Value: object being stored
• Key: SHA-1 hash of object

5. COMMIT
5 basic pieces of data
• Reference to top-level tree (folder) of snapshot
– Files/folders at the time of the commit
• Reference to parent commit
• Author with timestamp
• Committer with timestamp
• Commit message

6. FILE LOCATIONS IN GIT
• Working Directory
• Index (Staging Area)
• Repository
Working
Directory
Index
Repository
git add
git commit

7. FIXES FOR
COMMON
ISSUES

8. FIXING TYPOS/SMALL MISTAKES
• Typo in branch name
– git branch –m [new_name]
• Typo in your commit message
• Forgot to include a file
• Found a small bug after committing
– git commit --amend (--no-edit)
• Accidentally included changes
– git reset HEAD~1 (--soft)

9. ADDED TO WRONG BRANCH
• Need change from another branch
– git checkout [branch_to_add_to]
– git cherry-pick [commit_hash]
• Accidentally committed to `develop`
– git branch [new_name]
– git reset origin –hard
– git checkout [new_name]

10. CLEANING UP HISTORY BEFORE
PUSHING

11. CLEANING UP HISTORY BEFORE
PUSHING
• Use cases:
– Condense history
– Split commit
– Pretend things never happened
• Commands:
– git rebase –i origin

12. GOLDEN RULE OF REBASING
“Never rebase a shared branch.”
• Practical Golden Rule:
1. Determine the base commit
2. Do not rebase if anything past base commit is shared
B
A
D
C Pushed to
Origin

13. INTERACTIVE REBASE
Basic Syntax:
git rebase –i [<commit>]
Shows each commit ahead of the root commit and lets you decide what to do with them.
• Reorder commits
• Execute command against commit.
– pick: keep commit as-is
– drop: remove commit from history
– reword: keep contents of commit, but change message
– squash/fixup: amend previous commit with this one
– edit: pause rebase after commit to allow for amending
• git rebase –continue
– …

14. RECOVERING
FROM
CATASTROPHIC
FAILURE

15. Remember the Git
fundamentals
• When in doubt, just delete
everything and re-clone
• Noone can see your mistakes
if they no longer exist…
SO SOMETHING WENT
WRONG…

16. Remember the Git
fundamentals
• When in doubt, just delete
everything and re-clone
• Noone can see your mistakes
if they no longer exist…
SO SOMETHING WENT
WRONG…

17. Remember the Git
fundamentals
• Every commit is just an
object in the repository with
a hash
• Commits are read-only. You
cannot change a commit, you
can only create new ones.
SO SOMETHING WENT
WRONG…

18. GIT REFLOG
Basic Syntax:
git reflog [-n <number>]
• See entries in the “Reference Log”, along with their hashes
• You can reset a branch back to a “pre-catastrophic-
failure” hash

19. SUMMARY
H O W D O I R E M E M B E R A L L T H A T ?

20. CHEAT SHEET (FIXING COMMITS)
• Rename Branch
– git branch –m [new_name]
• Adjust previous commit
– git commit --amend --no-edit
• Copy commit from another branch
– git cherry-pick [commit]
• Accidental commits on `develop`
– git branch [new_branch]
– git reset origin --hard
– git checkout [new_branch]
• Clean up history
– git rebase –i origin
– move, fixup, squash, drop
• Split commit
– git rebase –I origin
– “edit”
– git reset HEAD~1
– Make new commits
– git rebase --continue
• Catastrophic failure
– git reflog
– get reset [some_commit_in_past]

21. CHEAT SHEET (USEFUL COMMANDS)
• Create new local branch
– git checkout –b [new_branch]
• Push locally created branch to BitBucket
– git push –u origin HEAD
• Update with latest from develop (add to end)
– git pull origin develop
• Update with latest from develop (add to beginning)
– git pull origin develop --rebase