Git and Github: Tips and tricks

Presentation for HackMcGill. Intro to Git/Github plus various tips and tricks, all in one.

Transcript

1. HackMcGill :: January 29, 2014
   tips & tricks
   and
   :
   

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2. about me
   - Wendy Liu
   - 4th year Math & CS
   - 3 years experience with Git
   - 137-day Github commit streak
   - dellsystem on Twitter, Github, IRC
   

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3. what is git?
   

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4. what is git?
   version control system!
   

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5. svn/perforce: local vs. remote
   comparison to other systems
   

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6. svn/perforce: local vs. remote
   hg/bzr: faster, more control
   comparison to other systems
   

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7. svn/perforce: local vs. remote
   hg/bzr: faster, more control
   cvs/rcs: no comparison
   comparison to other systems
   

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8. backup_dec_1_2012.zip backup_dec_8_2012.zip backup_dec_15_2012.zip
   backup_dec_22_2012.zip backup_dec_29_2012.zip backup_jan_5_2012.zip
   backup_jan_12_2012.zip backup_jan_19_2012.zip backup_jan_26_2012.zip
   

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9. report_v1.doc report_v2.doc report_v3.doc report_v4.doc
   

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10. keeps track of changes
    enter git.
    

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11. keeps track of changes
    extremely flexible
    enter git.
    

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12. keeps track of changes
    extremely flexible
    developed by linus torvalds
    enter git.
    

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13. keeps track of changes
    extremely flexible
    developed by linus torvalds
    completely free to use (and open source!)
    enter git.
    

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14. keeps track of changes
    extremely flexible
    developed by linus torvalds
    completely free to use (and open source!)
    primarily command-line
    enter git.
    

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15. website
    what is github?
    

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16. website
    collaborative coding, via git
    what is github?
    

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17. website
    collaborative coding, via git
    (mostly) free to use
    what is github?
    

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18. website
    collaborative coding, via git
    (mostly) free to use
    major part of developer ecosystem (esp. OSS)
    what is github?
    

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19. why git?
    

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20. why git?
    diffs
    

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21. why git?
    diffs
    backups
    

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22. why git?
    diffs
    backups
    collaboration
    

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23. what git can do for you
    versioning
    easy collaboration
    blame
    tracking down bugs
    safe experimentation
    statistics
    

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24. what github can do for you
    issue-tracking
    even easier collaboration
    remote backups
    access your files from anywhere
    graphical, easy-to-use UI
    

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25. now: how git works
    

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26. repository
    directory on filesystem
    just metadata (changes)
    manual grouping of changes
    

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27. commit
    group of logically-related changes
    1 or more files (add/delete/modify)
    

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28. staging index
    CHANGES I WANT IN MY NEXT COMMIT
    ALL THE OTHER CHANGES
    

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29. git commit -m 'test'
    CHANGES I WANT IN MY NEXT COMMIT
    ALL THE OTHER CHANGES
    a new commit, with message 'test'
    

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30. CHANGES I WANT IN MY NEXT COMMIT
    ALL THE OTHER CHANGES
    the commit with message 'test'
    (nothing here yet)
    

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31. your computer
    REMOTE REPOSITORIES
    LOCAL REPOSITORY
    some server another server github
    

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32. now: git tips
    

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33. rebasing
    git rebase -i [start commit]
    reorder, reword, edit, squash commits
    

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34. amending
    git commit --amend
    staged changes become part of previous commit
    

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35. force pushing
    git push origin master -f
    useful after amending/rebasing
    

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36. multiple remotes
    git remote add origin [url]
    git remote add upstream [different URL]
    useful when pulling from other developers
    

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37. patch
    git add --patch
    stage one chunk at a time
    

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38. diffing
    git diff (unstaged)
    git diff --cached (staged)
    git diff --check (whitespace errors)
    

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39. colours
    git config --global color.ui auto
    

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40. fix your whitespace
    git stripspace
    git apply --whitespace=fix
    

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41. good commit messages
    Fix bug (50 chars max, capitalised, imperative)
    Longer description explaining what the commit does.
    Wrap at 72 characters. Don't forget the blank line.
    bit.ly/gitcommit
    

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42. bisect
    git bisect (or, "when did this bug first appear?")
    

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43. ignoring
    .gitignore (untracked files)
    git update-index --assume-unchanged (tracked files)
    git status --ignored
    

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44. better pulls
    git pull vs git fetch & git merge
    

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45. aliases
    git s = git status
    git add = git add --patch
    git ds = git diff --staged
    git amend = git commit --amend
    git say = git commit -m
    git un = reset --soft HEAD^1
    

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46. fixing merge conflicts
    1. Don't panic
    2. git status
    3. Look for the <<<
    4. Stage & commit
    

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47. moving files
    git mv [source] [destination]
    instead of:
    mv [source] [destination]
    git rm [source]
    git add [destination]
    

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48. sensitive data
    help.github.com/articles/remove-sensitive-data
    

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49. selective staging
    git add --update (only tracked files)
    git add --all (all files)
    

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50. view configuration
    git config --list
    

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51. pushing to remotes
    git push origin master
    git push origin localbranch:remotebranch
    git push origin :remotebranch (deletes it)
    

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52. branch tracking
    git push origin master -u
    git push origin local:remote -u
    

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53. stashing edits
    git stash
    git stash apply
    git stash pop (applies, then removes from stack)
    

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54. fixing mistakes
    git checkout (undo edits)
    git reset --soft (keeps edits)
    git reset --hard (loses edits)
    

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55. merge strategies
    git merge --strategy=[strategy]
    strategies: recursive (default), ours, theirs, etc
    

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56. now: github tips
    

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57. keyboard shortcuts
    press ? to bring up the help
    

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58. issues in commits
    "Fix #54" -> closes issue #54 from the commit
    "For #54" -> links to #54 from commit, & vice versa
    

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59. all from your browser
    edit, commit, send a pull request
    ... all without leaving your browser
    

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60. blame
    who introduced this line, and when, and why
    

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61. file rendering
    markup, geoson, csv, and more
    

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62. integration with travis
    continuous integration (automated testing)
    

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63. thanks!
    git-scm.com/book
    help.github.com
    

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