Refactor or Die

a Lightning talk @ Ruby Hiroba 2013

Transcript

1. REFACTOR
   O R
   D I E
   

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2. Sho Kusano
   @rosylilly
   Engineer
   

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4. http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers
   Sandi Metz’ rules for developers
   

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5. 1
   http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers
   Sandi Metz’ rules for developers
   Classes can be no longer than
   one hundred lines of code
   

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6. 2
   http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers
   Sandi Metz’ rules for developers
   Methods can be no longer than
   five lines of code
   

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7. 3
   http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers
   Sandi Metz’ rules for developers
   Pass no more than four
   parameters into a method.
   Hash options are parameters.
   

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8. 4
   http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers
   Sandi Metz’ rules for developers
   Controllers can instantiate
   only one object.
   Therefore, views can only know about one instance
   variable and views should only send messages to that
   object (@object.collaborator.value is not allowed)
   

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9. 0
   http://robots.thoughtbot.com/post/50655960596/sandi-metz-rules-for-developers
   Sandi Metz’ rules for developers
   You should break these rules
   only if you have a good reason or
   your pair lets you
   

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10. Let’s refactor
    your codes!
    

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12. Where we can start refactoring?
    

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13. rubocop
    https://github.com/bbatsov/rubocop
    Save your coding rules
    

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14. $ rubocop
    ...
    C:264: Surrounding space missing for '{'.
    C:264: Surrounding space missing for '{'.
    C:264: Space missing to the left of '}'.
    C:282: Line is too long. [98/79]
    C:283: Line is too long. [81/79]
    C:284: Method has too many lines. [45/10]
    C:287: Prefer single-quoted strings when you don't need string interpolation
    or special symbols.
    C:288: Line is too long. [115/79]
    C:298: Indent when as deep as case.
    C:300: Indent when as deep as case.
    C:305: Line is too long. [98/79]
    C:310: Indent when as deep as case.
    C:318: Indent when as deep as case.
    C:320: Indent when as deep as case.
    ...
    

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15. simplecov
    https://github.com/colszowka/simplecov
    Don’t end with “FIXME”
    

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16. $ COV=1 rspec spec/models
    ...............................................................
    Finished in 1.62 seconds
    63 examples, 0 failures
    Coverage report generated for RSpec to coverage. 140 / 140 LOC (100.0%)
    covered.
    

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17. Module#deprecate
    http://api.rubyonrails.org/classes/Module.html#method-i-deprecate
    Don’t get on the time machine
    

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18. class DirtyModel
    def old_method
    # body omitted ...
    end
    deprecate :old_method
    def new_method
    # body omitted ...
    end
    if Rails.env.test?
    alias_method :old_method, :new_method
    end
    end
    

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19. Let’s refactor
    your codes!
    

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20. WE ARE
    HIRING !!
    Let’s refactor our codes together !!
    http://info.cookpad.com/jobs/?affcd=geo2a
    

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21. One more dish
    

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22. 24-hours
    Hackathon Competition
    http://info.cookpad.com/24contest4
    Twitter: @24contest / Hashtags: #24contest
    2013 / 06 / 15 09:00 a.m. ʙ 06 / 16 09:00 a.m.
    

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23. Thank you for listening
    https://speakerdeck.com/rosylilly/refactor-or-die
    

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24. sora_h
    my wife
    Special Thanks
    

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