Commit often, perfect later, publish once – Hello, git – Branching
Commit often, perfect later, publish once – Hello, git – Branching
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git-reveal
git slides — http://agross.github.io/git-revealOn Github agross / git-reveal
Commit often, perfect later, publish once
Hello, git
A completely ignorant, childish person with no manners. — Urban Dictionary$ /dont-panic/
$ git <verb>
$ git help <verb> $ git <verb> --help
$ git init Initialized empty Git repository in /scratch/.git/ $ echo hello, world > hello.txt $ git add hello.txt $ git commit -m "my first commit!" [master (root-commit) ad9a291] my first commit! 1 file changed, 1 insertion(+) create mode 100644 hello.txt
$ git log --patch
commit ad9a291416165bb95a541321a7acf9cef9731c1d
Author: Alexander Groß <agross@therightstuff.de>
Date: Sat Feb 6 12:41:24 2010 +0100
my first commit!
diff --git a/hello.txt b/hello.txt
new file mode 100644
index 0000000..4b5fa63
--- /dev/null
+++ b/hello.txt
@@ -0,0 +1 @@
+hello, world
Content Lifecycle
Staging Area = Power
It allows you to do partial operations with git {add|checkout|reset HEAD} --patchBranching
Simple history
There is another pointer: HEAD
Creating a branch
$ git branch testing <where>(<where> defaults to HEAD)
Current branch = where HEAD is
$ git checkout testing
A Shortcut
$ git checkout -b <name> <where> == $ git branch <name> <where> && git checkout <name>
Advancing the testing branch
$ git commit -am "work on testing"
Back to master
$ git checkout master
Advancing the master branch
$ git commit -am "work on master"
Integration
Your options:
Visualizing a "Git Merge" pic.twitter.com/RQJ2AV7JRQ
— David Rousset (@davrous) August 20, 2016Diverged History
git merge
$ git checkout master $ git merge experimentThis is a recursive merge, as it integrates two diverged branches.
Undoing the merge
$ git reset --hard C3
Linear history
A git merge special case
$ git checkout master $ git merge experimentThis is a fast-forward merge as the master pointer can be moved from C3 to C4 without losing commits reachable from master.
Controlling git merge behavior
$ git merge --ff-only
Enforces a fast-forward merge, aborts if history is diverged.
$ git merge --no-ff
Enforces a recursive merge, even if a fast-forward merge would be possible.
Controlling git merge recursive strategy
$ git merge --strategy-option ours
Prefer our changes when encountering conflicts.
$ git merge -X theirs
Prefer their changes when encountering conflicts.
Even more options
- git cherry-pick <SHA>Pick a single commit from another branch.
- git merge --squash topicApply commits from the topic branch squashed into a single commit on top of HEAD.
- git merge feature/login bugfix/42 experiment/fooIntegrate any number of non-conflicting branches with a single merge commit.
- git merge --strategy=ours obsoleteIntegrate history, but ignore (undo) all changes introduced by the obsolete branch.
git rebase
$ git checkout experiment $ git rebase masterCommit C4 is applied on top of master as C4'.
$ git rebase origin/master pic.twitter.com/pAHtrPrm84
— Alejandro AR (@kinduff) January 16, 2015This is from a project I am working on. #git #rebase vs. #merge pic.twitter.com/TRgsq7BSin
— MiCHΛΞl (@michaelhenke) April 6, 2015Complex Rebase
How to get rid of C3 when rebasing client on master?Complex Rebase
…is easy when you know the syntax$ git rebase --onto master server client
Branching Strategies
Feature Branches Provide Isolation
Again, you have two options:
- git merge if you want to keep information about integrated branches
- git rebase if you do not care
