![(Local Branch) Merge Strategy II(Local Branch) Merge Strategy II
Merge Commit
$ git checkout -b new-branch
$ git commit -am 'commit'
$ git checkout master
$ git merge new-branch --no-ff
$ git log
commit 33a935fb06182ba9c6868a9bf85efe7c2e5770f3
Merge: 1d9f153 efd5daa
Author: XXX
Date: Mon Nov 26 11:41:25 2018 +0800
Merge branch 'new-branch'
commit efd5daabfc1d4366f197dc71c3edfd251b0396d0
Author: XXX
Date: Mon Nov 26 11:41:00 2018 +0800
commit
2018-11-26 11:41 Michael Fong M─┐ [master] Merge branch 'new-branch'
2018-11-26 11:41 Michael Fong │ o commit
2018-11-21 15:58 Michael Fong o─┘ {origin/master} {origin/HEAD}
Branching graph
4 . 9](https://image.slidesharecdn.com/did-you-git-yet1-181207030017/85/Did-you-git-yet-19-320.jpg)
Did you git yet?
- 1. Did you yet?Did you yet? “ Git is a British English slang roughly equivalent to "unpleasant person". 1 . 1
- 2. ChangelogChangelog v 1.0.1 Basic git concept and commands git flow concept 1 . 2
- 3. Design GoalDesign Goal Git is an open source, distributed version control system designed to be fast and branching Decentralized vs Centralized (SVN / Perforce / CVS) Suitable for fast development of multiple branch in parallel Git Generally DOES NOT delete data Git Generally append data in version tree. Recovering deleted data could be tricky 2 . 1
- 4. Work FlowWork Flow Index 2 . 2
- 5. Pros / ConsPros / Cons Centralized Decentralized Concurrent Access Control File Locking N.A; Manual intervention is required to resolve the conflict. Offline Development Unable to submit changelist; create a tag / branch. Able to commit to local repository Remote Server One Centralized server multiple remote repo 2 . 3
- 6. Pros / ConsPros / Cons Centralized Decentralized Concurrent Access Control File Locking N.A; Manual intervention is required to resolve the conflict. Offline Development Unable to submit changelist; create a tag / branch. Able to commit to local repository Remote Server One Centralized server multiple remote repo 2 . 3
- 7. Pros / ConsPros / Cons Centralized Decentralized Concurrent Access Control File Locking N.A; Manual intervention is required to resolve the conflict. Offline Development Unable to submit changelist; create a tag / branch. Able to commit to local repository Remote Server One Centralized server multiple remote repo 2 . 3
- 8. Git ObjectsGit Objects $ ll .git/ 4096 Apr 7 2018 branches/ 528 Nov 9 17:32 COMMIT_EDITMSG 284 Nov 8 20:48 config 73 Apr 7 2018 description 272 Jun 18 00:04 FETCH_HEAD 23 Nov 9 12:35 HEAD 4096 Apr 7 2018 hooks/ 16153 Nov 9 17:31 index 4096 Apr 7 2018 info/ 4096 Apr 7 2018 logs/ 4096 Aug 15 22:56 objects/ 41 Nov 8 20:49 ORIG_HEAD 107 Apr 7 2018 packed-refs 4096 Nov 6 14:31 refs/ 3 . 1
- 9. CommitCommit A.k.a. Ref / Reference Alias to a hash (SHA-1) commit hash See the SHA-1 commit hashes $ git log commit 059806c1e05ed7a3a387da16d05844f63c47251a Author: Author Name <Author Email> Date: Fri Nov 9 17:31:31 2018 +0800 Commit Title Commit Description commit 91e622c61f99f24dbda741050e251837a643f6c9 Author: Michael Fong <[email protected]> Date: Thu Nov 8 20:26:33 2018 +0800 Another Commit 3 . 2
- 10. HEADHEAD HEAD file is a symbolic ref for the current branch $ tree .git/refs/heads/ .git/refs/heads/ ├── ConnectionPool ├── LocalhostJmxConnectorServerProxyDemo ├── master ├── RACBenchmark ├── string-builder-perf-death-match ├── study-fadvise-effect ├── tuneWarmUpIteration └── unintentional-obj-retension 0 directories, 8 files $ cat .git/refs/heads/master 059806c1e05ed7a3a387da16d05844f63c47251a Uses HEAD file to store latest commit info of the branch 3 . 3
- 12. Initialize Git SettingInitialize Git Setting User Information $ git config --global user.name "John Doe" $ git config --global user.email [email protected] Editor Information # Set default editor to vim $ git config --global core.editor vim # Set default editor to emacs $ git config --global core.editor emacs List current settings $ git config --list [email protected] user.name=Michael Fong core.editor=vim ... 4 . 2
- 13. Clone RepositoryClone Repository $ git clone https://github.com/<username>/<project> Clone repository via Https $ git clone ssh://github.com/<username>/<project> Clone repository via SSH Show current repository status $ git status On branch <local-repo> Your branch is up-to-date with <remote-repo>. nothing to commit, working directory clean <If there is (new) file different from current ver, they will appear here> # Diff against local workspace and index $ git diff 4 . 3
- 14. Commit ChangesCommit Changes # add new files $ git add 1.file # add by pattern $ git add *.file # add by everything under directory $ git add ./ $ git add -all # remove file from tracking $ git rm file.py # Diff against local repo and index $ git diff --cached Staging Changes Update to local Staging Area / Index Commit Changes Update to local repo # Enter commit commit description in default editor $ git commit # alternatively, one command commit $ git commit -am "Enter your commit description" 4 . 4
- 15. Branch ManagementBranch Management # create a new branch $ git checkout master $ git branch new-branch # Alternatively, create a new branch from remote-repo/remote-branch $ git checkout <remote-repo>/<remote-branch> -b <local-branch> $ git checkout origin/master -b new-branch #Create a new branch from tag $ git checkout tags/<tag-name> -b new-branch Create a new local branch Switch to existing local branch List all Branches $ git checkout new-branch # (noarg - local branch; -r remote branch; -a all branch) $ git branch -av Delete Branch # Delete local repository $ git branch -d new-branch # Delete local repository by force $ git branch -D new-branch # Delete a branch from remote repository $ git push <remote-repo> :<branch-name> 4 . 5
- 16. Remote CommandRemote Command # Add a new remote repo $ git remote add origin <GIT_URL_HTTPS_or_SSH> # Update an existing remote repo $ git remote update origin <GIT_URL_HTTPS_or_SSH> Push to remote repo:branch # Fetch & Merge $ git pull # Fetch from remote repo $ git fetch origin # Merge from remote branch master $ git merge origin master Pull from remote repository Add / Update a remote repository # push to remote-repo (origin) / remote-branch (master) $ git push <remote-repo> <local-branch>:<remote-branch> $ git push origin master:master $ git push origin master $ git push origin new-branch:new-branch 4 . 6
- 17. (Local Branch) Merge Strategy I(Local Branch) Merge Strategy I Fast Forward Merge When the merge resolves as a fast-forward, only update the branch pointer, without creating a merge commit. Default merge strategy $ git checkout master $ git merge new-branch (--ff) 4 . 7
- 18. (Local Branch) Merge Strategy II(Local Branch) Merge Strategy II Non Fast Forward Merge Create a merge commit $ git checkout master $ git merge new-branch --no-ff 4 . 8
- 19. (Local Branch) Merge Strategy II(Local Branch) Merge Strategy II Merge Commit $ git checkout -b new-branch $ git commit -am 'commit' $ git checkout master $ git merge new-branch --no-ff $ git log commit 33a935fb06182ba9c6868a9bf85efe7c2e5770f3 Merge: 1d9f153 efd5daa Author: XXX Date: Mon Nov 26 11:41:25 2018 +0800 Merge branch 'new-branch' commit efd5daabfc1d4366f197dc71c3edfd251b0396d0 Author: XXX Date: Mon Nov 26 11:41:00 2018 +0800 commit 2018-11-26 11:41 Michael Fong M─┐ [master] Merge branch 'new-branch' 2018-11-26 11:41 Michael Fong │ o commit 2018-11-21 15:58 Michael Fong o─┘ {origin/master} {origin/HEAD} Branching graph 4 . 9
- 20. (Remote Branch) Merge(Remote Branch) Merge Merge between two branch on remote repository Github: Pull Request Gitlab: Merge Request Non fast forward merge Default strategy for merging PR Usually configurableg 4 . 10
- 21. Merge StrategyMerge Strategy Log Branch Graph Fast Forward Clean Less intuitive No Fast Forward Merge commit More intuitive 4 . 11
- 22. Merge ConflictsMerge Conflicts Manual intervention is required. After self correction is done; add and commit the conflict files. $ git add index.html $ git commit 4 . 12
- 23. Rebase IRebase I Moving a branch onto a new base commit Rebasing onto master will take all commits from master and apply your branch commits on top one by one. Later could combine with merge to master 4 . 13
- 24. Rebase IIRebase II If combined with squash, there will possibly be only one commit. 4 . 14
- 25. Squash ISquash I squash is a mechanism to consolidate multiple commit into one. It comes with rebase / merge command 4 . 15
- 26. Squash IISquash II pick commit1 (528f601) squash commit2 (a96173c) edit commit3 (eadd9c2) 4 . 16
- 27. Squash IIISquash III Squashing commit 2 into commit 1 4 . 17
- 28. Squash IVSquash IV Edit commit 3 4 . 18
- 29. Cherry PickCherry Pick Given one or more existing commits, apply the change each one introduces, recording a new commit for each. $ git cherry-pick C2 C4 4 . 19
- 30. TagTag Annotation to represent release Create a tag List all tags $ git tag -a <tag-name> -m 'description' $ git push <remote-repo> <tag-name> $ git tag -l Show tag metadata $ git show <tag-name> Delete a tag $ git tag -d <tag-name> $ git push <remote-repo> <tag-name> 4 . 20
- 32. StashStash How to save unfinished implementation temporarily? Save the current state of work. # Save current work, and rollback to HEAD keep current work space clean $ git stash -u # Reload latest stash record $ git stash pop # List stash record $ git stash list 5 . 2
- 33. Undo Commit IUndo Commit I $ git reset --soft HEAD~1 $ git diff --cached $ git reset HEAD~1 $ git diff $ git reset --hard HEAD~1 Reset current HEAD to the specific state Changes are UNSTAGED Changes are STAGED Changes are REMOVED from log 5 . 3
- 34. Undo Commit IIUndo Commit II $ git checkout path/to/filename $ git revert commit-hash Reverts a commit with another commit Restores the file to the latest version in HEAD, changes are dropped 5 . 4
- 35. Reference LogReference Log Historical records when the tips of branches and other references were updated in the LOCAL repository. Helpful when you want to look up historical commit $ git reflog Maybe your last resort to undo bad commit Use at your RISK! $ git reset --hard HEAD@{n} 5 . 5
- 36. Bash Alias IBash Alias I # Nice format for `git log` alias git.log="git log --graph --abbrev-commit --decorate -- format=format:'%C(bold blue)%h%C(reset) - %C(bold cyan)%aD%C(reset) %C(bold green)(%ar)%C(reset) %C(bold cyan) (committed: %cD)%C(reset) %C(auto)%d%C(reset)%n'' %C(white)%s%C(reset)%n'' %C(dim white)- %an <%ae> %C(reset) %C(dim white)(committer: %cn <%ce>)%C(reset)' --all" * 059806c - Fri, 9 Nov 2018 17:31:31 +0800 (2 days ago) (committed: Fri, 9 Nov 2018 17:31:31 +080 | Add unit test to ByteBuf | - Michael Fong <[email protected]> (committer: Michael Fong <[email protected] | * f5832fa - Fri, 9 Nov 2018 12:35:40 +0800 (2 days ago) (committed: Fri, 9 Nov 2018 12:35:40 +0 | | squash | | - Michael Fong <[email protected]> (committer: Michael Fong <mcfong.open@gmail | * f5f556a - Tue, 6 Nov 2018 19:54:47 +0800 (5 days ago) (committed: Thu, 8 Nov 2018 20:49:30 +0 |/ Add fadvise64 | - Michael Fong <[email protected]> (committer: Michael Fong <mcfong.open@gmail * 91e622c - Thu, 8 Nov 2018 20:26:33 +0800 (3 days ago) (committed: Thu, 8 Nov 2018 20:42:14 +080 | Copy libnative-utility.so to target/classes for java-jni | - Michael Fong <[email protected]> (committer: Michael Fong <[email protected] * 794bf26 - Wed, 7 Nov 2018 16:18:03 +0800 (4 days ago) (committed: Thu, 8 Nov 2018 00:45:32 +080 5 . 6
- 37. tigtig Installation $ sudo apt-get install tig log $ tig log “ ncurses-based text-mode interface for git. status $ tig status 5 . 7
- 39. ProblemsProblems Everyone has a copy. Unfortunately, NOT the same copy! Which master is more up to date? Requiring Discipline Methodology 6 . 2
- 40. Ref Git Flow MethodologyGit Flow Methodology 6 . 3
- 41. Branching ModelsBranching Models master - ONE true MASTER develop feature Feature branches typically exist in developer repos only, not in origin release Release branches support preparation of a new production release. hot-fix When a critical bug in a production version must be resolved immediately, a hotfix branch may be branched off from the corresponding tag on the master branch that marks the production version. 6 . 4
- 42. ToolTool Provide high level operation github/git-flow/ Git Flow cheatsheet 6 . 5
- 43. ReferenceReference Linux Travolds on git Git-Basics Learn How to Git tig https://www.youtube.com/embed/4XpnKHJ Aok8?enablejsapi=1 7