Git 102 - Speaker Deck

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Git 102 @timblair

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All Things All People to Git is

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Headache Including a massive

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154 Commands how many do you know?

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git-config

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git-config 200+ Options

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git-config git config option.name value Set value

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git-config git config option.name Get value

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git-config git config --unset option.name Unset value

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git-config /etc/gitconfig (--system) ~/.gitconfig (--global) $GIT_DIR/config (--local) File Locations

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git-config [user] name = Tim Blair email = [email protected] [color] diff = auto status = auto branch = auto [alias] co = checkout ci = commit st = status -sb

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Aliases

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Aliases Efficiency

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Aliases Memory Space

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vi ~/.gitconfig git config --global alias.ci commit Or Aliases

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git config alias.st status Internal Aliases Aliases

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Internal Aliases Aliases Execute from the current path

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git config alias.st "!git status" External Aliases Aliases

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External Aliases Aliases Execute from the Repo root

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co = checkout ci = commit cia = commit -a st = status -sb br = branch Aliases

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pl = !git pull --rebase --prune && \ git submodule update --init Aliases

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lg = log --color --graph --abbrev-commit \ --pretty=format:'%Cred%h%Creset -%C(yellow)%d %Creset %s %Cgreen(%cr) %C(blue)<%aN>%Creset' Aliases

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Aliases

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merged = !git branch -r --merged origin/master \ | grep -v master \ | grep -v HEAD | sed 's/ origin\\///g’ ! rm-branch = !sh -c \ \"(git branch -D $1 2>/dev/null || true) && \ git push origin :$1\" - ! rm-merged = !git merged | xargs -L1 git rm-branch Aliases

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publish = !git push -u origin \ `git symbolic-ref --short HEAD` ! finish = !OLD_BRANCH="`git symbolic-ref --short HEAD`" \ && git co master && git pl \ && git br -d "$OLD_BRANCH" Aliases

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snapshot = !git stash save "snapshot: $(date)" \ && git stash apply "stash@{0}" Aliases

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Aliases nope = !git clean -dxf && git reset --hard

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Aliases alias g='git'

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Custom Commands

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Custom Commands Alias++

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Custom Commands 1 Create an executable file called git-foo

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Custom Commands 2 Add the file to your path

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Custom Commands 3 Call it like `git foo`

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Custom Commands #!/bin/bash # Usage: git merge-point SHA ! AIM=${2-master} ! git rev-list --ancestry-path $1..$AIM | grep -f <(git rev-list --first-parent $1..$AIM) | tail -n 1 | xargs git --no-pager show --shortstat

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Dealing Remotes with

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git pull fetch + merge is the default Dealing with Remotes

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git pull fetch + rebase is better Dealing with Remotes

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Dealing with Remotes set pull to rebase for new branches branch.autosetuprebase always

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Dealing with Remotes merge instead of fast-forwarding merge.ff false

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git push default is to push all branches Dealing with Remotes

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Dealing with Remotes Push only current branch to upstream push.default upstream

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Dealing with Remotes new default setting in git 2.0 push.default simple

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git-up Rebase on pull + update all branches Dealing with Remotes github.com/aanand/git-up

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Auto-Completion

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Auto-Completion local and remote branch + tag names git subcommands file paths in the working directory and index common --long-options

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git auto-completion for your bash Auto-Completion source `brew --prefix \ git`/etc/bash_completion.d/git-completion.bash

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github.com/git/git/blob/master/contrib/completion/git-completion.zsh Auto-Completion zsh wrapper

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oh-my-zsh plugin Auto-Completion gitfast

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Auto-Correction

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Auto-Correction $ git pusg git: 'pusg' is not a git command. See 'git --help'. ! Did you mean this? push

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Auto-Correction correct common command typos in 10 deciseconds help.autocorrect 10

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Auto-Correction $ git config --global help.autocorrect 10 ! $ git pusg WARNING: You called a Git command named 'pusg', which does not exist. Continuing under the assumption that you meant 'push' in 1.0 seconds automatically...

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Lost Commits

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local history of branch tip updates Lost Commits git-reflog

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Lost Commits 06770a0 HEAD@{0}: rebase finished: returning to refs/heads/master 06770a0 HEAD@{1}: checkout: moving from master to 06770a0c b022a35 HEAD@{2}: checkout: moving from msg_id_refactor to master 912785c HEAD@{3}: commit: Refactor #message[_id] to avoid extra lookups b022a35 HEAD@{4}: checkout: moving from master to msg_id_refactor b022a35 HEAD@{5}: checkout: moving from cache-negative-lookups to master 704d342 HEAD@{6}: commit: Make conformity specs less brittle 2d9ea86 HEAD@{7}: commit: Just enabled pipelining once, not every time 024227d HEAD@{8}: commit: Clean up conformity checker 28d6a12 HEAD@{9}: commit: Break conformity checking logic out of member ed5b843 HEAD@{10}: cherry-pick: Use simpler class var references b022a35 HEAD@{11}: checkout: moving from master to cache-negative-lookups b022a35 HEAD@{12}: rebase finished: returning to refs/heads/master b022a35 HEAD@{13}: checkout: moving from master to b022a35e

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verify connectivity of git objects Lost Commits git-fsck

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Finds dangling commits and tags git fsck --lost-found Lost Commits

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Amending Commits your

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Amending Commits git commit --amend

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Amending Commits git commit --amend --no-edit amend the last commit and reuse the commit message

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Amending Commits git commit --amend -C HEAD amend the last commit and reuse all metadata

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Revision Selection

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Revision Selection SHA (long and short) ancestry commit message search time-based

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Revision Selection git show HEAD # By alias git show 12a86bc38 # By revision git show v1.0.1 # By tag git show feature132 # By branch name git show 12a86bc38^ # Commit parent git show 12a86bc38~2 # Grandparent git show master@{yesterday} # Time relative git show master@{2.hours.ago} # Time relative git show :/message # Commit message

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Switching Branches between

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Switching Branches git checkout -

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Switching Branches $ git checkout - Switched to branch 'master' ! $ git checkout - Switched to branch 'feature' ! $ git checkout - Switched to branch 'master'

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git-diff

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try a different diff algorithm git-diff diff.algorithm ... myers, patience, histogram

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suppress whitespace differences git-diff git diff -w

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show inline word differences git-diff git diff --word-diff

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git-diff $ g diff --word-diff HEAD^ ! diff --git a/README.md b/README.md index 2dcccf8..15d5ca7 100644 --- a/README.md +++ b/README.md @@ -1 +1 @@ I'm likely to make a [-misteak-]{+mistake+} in here somewhere.

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check for bad whitespace git-diff git diff --check

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git-diff $ g diff --check ! README.md:1: trailing whitespace. +I'm likely to make a mistake in here somewhere.

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Crafting Commits perfect

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Less of a tip, more of a Crafting Commits plea

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each commit should concisely represent a Crafting Commits single concept

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that makes each commit easy to Crafting Commits understand

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that makes each commit easy to Crafting Commits review

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that makes each commit easy to Crafting Commits revert

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an untidy history is fine locally commit regularly Crafting Commits

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clean up before you push your history Crafting Commits

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Crafting Commits is your friend git rebase -i

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Each commit message should describe Crafting Commits what and why

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Crafting Commits Short (50 chars or less) summary of changes More detailed explanatory text, if necessary. Wrap it to about 72 characters or so. In some contexts, the first line is treated as the subject of an email and the rest of the text as the body. The blank line separating the summary from the body is critical (unless you omit the body entirely); tools like rebase can get confused if you run the two together. GitHub treats the first line as the title of the commit and the rest as the description. Further paragraphs come after blank lines. - Bullet points are okay, too - Typically a hyphen or asterisk is used for the bullet, preceded by a single space, with blank lines in between, but conventions vary here

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"Add X," not "Adds X" or "Added X" Auto-Completion imperative present use the

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make your commit history Crafting Commits tell a story

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Autosquash

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bf204f4 Add something I forgot f1c7e94 Add the other file 256beed Add some text to the README Autosquash your history

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Autosquash clean up before pushing git rebase -i

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pick 256beed Add some text to the README pick f1c7e94 Add the other file pick bf204f4 Add something I forgot Autosquash

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bf204f4 squash! Add some text to the README f1c7e94 Add the other file 256beed Add some text to the README Autosquash prefixed commits

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Autosquash helping you help yourself git rebase -i --autosquash

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pick 256beed Add some text to the README squash bf204f4 squash! Add some text to the README pick f1c7e94 Add the other file Autosquash

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And to Finish…

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Quick Tips reuse recorded resolution git-rerere

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Assisted binary search through commits git-bisect Quick Tips

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strips trailing whitespace and collapses newlines git-stripspace Quick Tips

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temporarily ignore changes to a file git update-index --assume-unchanged FILE Quick Tips --no-assume-unchanged to reverse it

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create a commit with no code changes git commit --allow-empty Quick Tips

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browse your local repo using gitweb git instaweb Quick Tips Requires lighttp: brew install lighttpd

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search through all of history git log -S'STRING' Quick Tips

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search through all of history git rev-list --all | xargs git grep -F 'STRING' Quick Tips

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The End you may now applaud