Bugs - What are they good for

Transcript

1. 1
   Bugs
   What are they good for?
   

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3. What is a bug?
   

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4. “First actual
   case of bug
   being found”
   Grace Hopper - 1947
   

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5. “I did find a bug
   in my apparatus”
   Thomas Edison - 1878
   

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6. The Crash <> Request Scale
   Crash Change Request
   ⚠
   

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7. Let’s ship some products
   

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8. Numbers only?
   

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9. Nope
   

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10. “You didn’t say you wanted
    to ship stuff to the Queen”
    

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11. “Well you should know
    how addresses work”
    

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12. The Crash <> Request Scale
    Crash Change Request
    ⚠
    

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13. Record Investigate Fix
    

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15. Reproduce It
    Fix It
    Ship It
    

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16. Find a reproducible scenario
    

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17. Speeds up fixing process
    

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18. accepted
    Closed Won
    

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19. paid
    Closed Lost
    

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20. context 'accepted order' do
    let(:order) { build(:order, status: 'accepted') }
    it 'returns "closed won"' do
    expect(deal_stage(order)).to eq('closed won')
    end
    end
    context 'paid order' do
    let(:order) { build(:order, status: 'paid') }
    it 'returns "closed won"' do
    expect(deal_stage(order)).to eq('closed won')
    end
    end
    

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21. def deal_stage(order)
    return 'enquired' if order.nil?
    return 'quoted' if order.open?
    return 'closed won' if order.accepted?
    'closed lost'
    end
    

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22. Lets you try out different solutions
    

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23. Makes it clear what to fix
    

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24. NoMethodError: undefined
    method `date’ for nil:NilClass
    

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25. def render(order)
    {
    id: order.id,
    delivery_date: order.delivery.date
    }
    end
    

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26. def render(order)
    {
    id: order.id,
    delivery_date: order.delivery&.date
    }
    end
    

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27. GET /api/v1/orders?status=delivered
    • Order 01
    • Order 02
    • Order 03
    

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28. Confidence that bug
    has been fixed
    

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29. Continuous Integration
    Heroku Review Apps
    Create App
    Precompile Assets
    Create/Migrate Database
    Launch App
    Code
    
    

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30. But what about actually fixing the bugs?
    

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31. def deal_stage(order)
    puts "What's happening?: #{order.inspect}"
    return 'enquired' if order.nil?
    puts "What's happening?: #{order.inspect}"
    return 'quoted' if order.open?
    puts "What's happening?: #{order.inspect}"
    return 'closed won' if order.accepted?
    puts "What's happening?: #{order.inspect}"
    'closed lost'
    end
    Puts Debugging
    

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32. github.com/pry/pry
    def deal_stage(order)
    binding.pry
    return 'enquired' if order.nil?
    return 'quoted' if order.open?
    return 'closed won' if order.accepted?
    'closed lost'
    end
    

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33. Is it really the culprit?
    Caching
    Third Party Libraries
    Recent Changes
    User
    

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34. Push
    Continuous Integration
    Deploy
    Revert
    Continuous Integration
    
    
    
    

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35. Record Investigate Fix
    Now
    Depends on
    Urgency/Impact
    

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36. My Latest Bug
    

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41. Reproduce It
    Don’t jump to conclusions
    

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