Git a life

Introduction to git: basic commands, merge and rebase examples, alias.

Transcript

1. git a life Fabrizio Monti @delphaber Torino Coding Society
2. Version Control System
3. Copy & Paste VCS project_last/ project_last_last/ project_last_last_20140428/ project/
4. Local VCSs
5. Centralized VCSs (CVS, Subversion, Perforce)
6. Distributed VCSs (git, mercurial, bazaar)
7. git "A completely ignorant, childish person with no manners." http://www.urbandictionary.com
8. Theory
9. Snapshots, not diffs Recording file diffs (SVN) Recording snapshots (git) https://www.atlassian.com/git/
10. Three states Git directory (local repository) Working directory/tree Staging area (index)
11. http://git-scm.com/book File Status Lifecycle unmodified modified staged untracked stage file commited edit file stage file commit file has been committed
12. 30 seconds example
13. http://lmgtfy.com/?q=install+git Install
14. $ git config --global user.name "John Wayne" $ git config --global user.email john@wayne.com Configuration
15. $ git init Create an empty repository
16. $ git status Show the working tree status
17. $ git status # On branch master # # Initial commit # # Untracked files: # (use "git add <file>..." to include in what will be committed) # # README.md # hello.rb nothing added to commit but untracked files present (use "git add" to track)
18. $ git add . Add file contents to the staging area
19. $ git status # On branch master # # Initial commit # # Changes to be committed: # (use "git rm --cached <file>..." to unstage) # # new file: README.md # new file: hello.rb #
20. $ git commit -m 'first commit' Record changes (to the repository)
21. $ git commit -m "first commit" [master (root-commit) c5f4b1e] first commit 0 files changed create mode 100644 README.md create mode 100644 hello.rb
22. $ git log Show commit logs
23. $ git log commit c5f4b1e43da12ba86ec7c61d2bfbcb39ed8a064e Author: John Wayne <john@wayne.com> Date: Fri Apr 25 15:52:01 2014 +0200 first commit
24. $ git status # On branch master nothing to commit (working directory clean)
25. Edit a file
26. $ git status # On branch master # Changes not staged for commit: # (use "git add <file>..." to update what will be committed) # (use "git checkout -- <file>..." to discard changes in working directory) # # modified: README.md # no changes added to commit (use "git add" and/or "git commit -a")
27. $ git diff Show changes
28. $ git diff diff --git a/README.md b/README.md index e69de29..75c0a6b 100644 --- a/README.md +++ b/README.md @@ -0,0 +1 @@ +I added this line!
29. $ git add README.md Add file contents to the staging area
30. $ git status # On branch master # Changes to be committed: # (use "git reset HEAD <file>..." to unstage) # # modified: README.md #
31. $ git commit -m 'change readme' Record changes (to the repository)
32. $ git log --oneline --decorate Show commit logs
33. $ git log --oneline --decorate 8783a9e (HEAD, master) change readme c5f4b1e first commit
34. … 30 seconds?
35. Undoing things
36. $ git commit --amend Change the last commit
37. $ git reset HEAD <file>... Remove a file from the staging area
38. $ git status # On branch master # Changes to be committed: # (use "git reset HEAD <file>..." to unstage) # # modified: README.md #
39. $ git checkout -- <file>... Restore a modified file
40. $ git status # On branch master # Changes not staged for commit: # (use "git add <file>..." to update what will be committed) # (use "git checkout -- <file>..." to discard changes in working directory) # # modified: README.md # no changes added to commit (use "git add" and/or "git commit -a")
41. Change history
42. C1 C2 C3 c0c6741a C4 485477ce 727987e1 da2f1cd5 master HEAD HEAD^ HEAD^^ HEAD^^^ HEAD~ HEAD~2 HEAD~3
43. $ git reset HEAD^ Remove last commit, but keep changes
44. C1 C2 C3 c0c6741a C4 485477ce 727987e1 da2f1cd5 master HEAD Changes in da2f1cd5 are now in your working directory You didn't lose any data
45. C1 C2 C3 c0c6741a C4 485477ce 727987e1 da2f1cd5 master HEAD
46. $ git reset --hard HEAD^ Remove last commit, discard changes
47. C1 C2 C3 c0c6741a C4 485477ce 727987e1 da2f1cd5 master HEAD Working directory has been restored to 727987e1 All changes in da2f1cd5 are lost.
48. HALP! I lost all of my work!
49. $ git reflog Where "was" my mind? http://youtu.be/qrdpliMfoAM
50. $ git reflog 727987e1 HEAD@{0}: reset: moving to HEAD^ da2f1cd5 HEAD@{1}: commit: fourth 727987e1 HEAD@{2}: commit: third 485477ce HEAD@{3}: commit: second c0c6741a HEAD@{4}: commit (initial): first C1 C2 C3 c0c6741a C4 485477ce 727987e1 da2f1cd5
51. $ git reset --hard HEAD@{1} HEAD is now at da2f1cd5 fourth C1 C2 C3 c0c6741a C4 485477ce 727987e1 da2f1cd5 master HEAD
52. Danger High voltage!
54. Branching
55. C1 C2 master HEAD
56. C1 C2 master HEAD feature 1 $ git branch feature1 Before
57. C1 C2 master HEAD feature 1 $ git checkout feature1 Before
58. $ git checkout -b feature1 (Shorter version)
59. Let's work on "feature1"
60. C1 C2 master HEAD feature 1 C3 C4
61. Boss called. Need fix on master. Now.
62. C1 C2 master HEAD feature 1 C3 C4 C5 C6 Before
63. OK. Let's merge feature1.
64. $ git merge feature1 Auto-merging index.html CONFLICT (content): Merge conflict in index.html Automatic merge failed; fix conflicts and then commit the result. $ git status On branch master You have unmerged paths. (fix conflicts and run "git commit") Unmerged paths: (use "git add <file>..." to mark resolution) both modified: index.html no changes added to commit (use "git add" and/or "git commit -a")
65. <<<<<<< HEAD <div id="footer">TCS al TAG Torino</div> ======= <div id="footer"> TorinoCodingSociety - TAG Torino </div> >>>>>>> feature1
66. $ git add index.html $ git commit
67. C1 C2 master HEAD feature 1 C3 C4 C5 C6 C7 Before
68. Rebase
69. C1 C2 master HEAD feature 1 C3 C4 C5 C6
70. C1 C2 master feature 1 C3 C4 C5 C6 C3' C4' HEAD $ git rebase master Before
71. C1 C2 master feature 1 C3 C4 C5 C6 C3' C4' HEAD $ git checkout master
72. C1 C2 master feature 1 C3 C4 C5 C6 C3' C4' HEAD $ git merge feature1 (Fast Forward) Before
73. Interactive Rebase
74. C1 C2 master HEAD feature 1 C3 C4 C5 C6
75. $ git rebase -i master
76. pick 3b9556b C3 Commit pick a9f5eb5 C4 Commit # Rebase 59ec99a..a9f5eb5 onto 59ec99a # # Commands: # p, pick = use commit # r, reword = use commit, but edit the commit message # e, edit = use commit, but stop for amending # s, squash = use commit, but meld into previous commit # f, fixup = like "squash", but discard this commit's log message # x, exec = run command (the rest of the line) using shell # # If you remove a line here THAT COMMIT WILL BE LOST. # However, if you remove everything, the rebase will be aborted. #
77. pick 3b9556b C3 Commit squash a9f5eb5 C4 Commit # Rebase 59ec99a..a9f5eb5 onto 59ec99a # # Commands: # p, pick = use commit # r, reword = use commit, but edit the commit message # e, edit = use commit, but stop for amending # s, squash = use commit, but meld into previous commit # f, fixup = like "squash", but discard this commit's log message # x, exec = run command (the rest of the line) using shell # # If you remove a line here THAT COMMIT WILL BE LOST. # However, if you remove everything, the rebase will be aborted. #
78. C1 C2 master HEAD feature 1 C3 C4 C5 C6 C7
79. Remotes
80. $ git clone git@github.com:delphaber/skuby.git $ git remote -v origin git@github.com:delphaber/git-a-life.git (fetch) origin git@github.com:delphaber/git-a-life.git (push) $ git remote add upstream git@github.com:welaika/skuby.git $ git remote -v origin git@github.com:delphaber/skuby.git (fetch) origin git@github.com:delphaber/skuby.git (push) upstreamgit@github.com:welaika/skuby.git (fetch) upstreamgit@github.com:welaika/skuby.git (push)
81. C1 C2 master HEAD
82. C1 C2 master HEAD origin/master $ git push origin master Before
83. C1 C2 master origin/master C3 $ git checkout -b feature2 feature2 HEAD Before
84. C1 C2 master origin/master C3 2 x $ git commit feature2 HEAD C5 C4 Before
85. C1 C2 master origin/master C3 $ git push -u origin feature2 feature2 HEAD C5 C4 origin/feature2 Before
86. Your colleague pushed two commits on origin, based on C3 (origin/master)
87. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 origin/master C6 and C7 are my colleague's commits. My git repository knowns nothing about them at the moment.
88. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 origin/master C6 and C7 are my colleague's commits. My git repository knowns nothing about them at the moment. $ git checkout master
89. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 C6 and C7 are my colleague's commits. My git repository knowns nothing about them at the moment. $ git merge feature2 origin/master
90. $ git push Push rejected. Non fast-forward.
91. God, why?
92. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 C6 and C7 are my colleague's commits. My git repository knowns nothing about them at the moment. origin/master
93. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 origin/master $ git fetch
94. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 origin/master $ git merge origin/master C8
95. C1 C2 master C3 feature2 HEAD C5 C4 origin/feature2 C7 C6 origin/master $ git push C8
96. $ git fetch + $ git merge = ============= $ git pull
97. Are you hungry?
98. Stashing
99. $ git stash $ git stash list stash@{0}: WIP on master: 5716ab8 fix bug $ git stash pop # useful alternatives $ git stash save --keep-index "comment" $ git stash save --include-untracked "comment"
100. Revert How to properly undo published commits $ git revert <commit>...
101. $ git tag <tagname> Mark a specific commit $ git push --tags
102. Tips & Tricks
103. Ignoring files
104. $ cat .gitignore *.gem *.rbc /.config /coverage/ /tmp/ /public/*.sql
105. Interactive staging
106. $ git add --patch . diff --git a/.gitignore b/.gitignore index f2c1360..d6c8ae0 100644 --- a/.gitignore +++ b/.gitignore @@ -30,5 +30,4 @@ build/ # .ruby-version # .ruby-gemset -# unless supporting rvm < 1.11.0 or doing something fancy, ignore this: -.rvmrc + Stage this hunk [y,n,q,a,d,/,e,?]?
107. Assume unchanged $ git update-index --assume-unchanged <file>
108. A better log
109. $ git log --oneline --decorate --graph --branches --remotes -20 * 5716ab8 (HEAD, tag: v1.0.0, origin/master, origin/HEAD, master) Merge branch 'feature1' |\ | * bd7e8aa (origin/feature1, feature1) commit | * a9f5eb5 commit |/ | * 38173a0 (feature2) commit | * b5499c7 commit | * 1814c66 (origin/feature2) commit | * 5bb5b65 commit |/ * 3b9556b commit * 59ec99a commit * 422c3ca commit * 8e7a219 Initial commit
110. $ git log --oneline --decorate --graph --branches --remotes --simplify- by-decoration * 5716ab8 (HEAD, tag: v1.0.0, origin/master, origin/HEAD, master) Merge branch 'feature1' * bd7e8aa (origin/feature1, feature1) commit | * 38173a0 (feature2) commit | * 1814c66 (origin/feature2) commit |/ * 8e7a219 Initial commit
111. $ git log --until=1.minute.ago $ git log --since=2.days.ago $ git log --since=1.hour.ago $ git log --since=1.month.ago --until=2.weeks.ago $ git log --since=2014-04-24 --until=2014-04-28
112. For GUI lovers
113. $ gitk --all
115. $ git gui ($ apt-get install git-gui)
117. $ tig --all For ncurses lovers ($ apt-get install tig)
119. .gitconfig http://bit.ly/1nbrKiC
120. [user] … [alias] addp = add -p . br = branch co = checkout ci = commit st = status unstage = reset HEAD -- unchange = checkout -- # log l = log --oneline --decorate --graph --branches --remotes -20 ll = log --oneline --decorate --graph --stat ls = log --oneline --decorate --graph --branches --remotes --simplify- by-decoration # list aliases al = !git config --get-regexp 'alias.*' | colrm 1 6 | sed 's/[ ]/ = /'
121. [core] excludesfile = ~/.gitignore_global [pull] rebase = true [color] ui = auto [color "branch"] … [color "diff"] … [color "status"] …
122. git a slice of pizza Fabrizio Monti @delphaber Torino Coding Society