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Bugs - What are they good for
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Leif Gensert
December 05, 2019
Technology
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Bugs - What are they good for
Leif Gensert
December 05, 2019
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Transcript
1 Bugs What are they good for?
None
What is a bug?
“First actual case of bug being found” Grace Hopper -
1947
“I did find a bug in my apparatus” Thomas Edison
- 1878
The Crash <> Request Scale Crash Change Request ⚠
Let’s ship some products
Numbers only?
Nope
“You didn’t say you wanted to ship stuff to the
Queen”
“Well you should know how addresses work”
The Crash <> Request Scale Crash Change Request ⚠
Record Investigate Fix
None
Reproduce It Fix It Ship It
Find a reproducible scenario
Speeds up fixing process
accepted Closed Won
paid Closed Lost
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
def deal_stage(order) return 'enquired' if order.nil? return 'quoted' if order.open?
return 'closed won' if order.accepted? 'closed lost' end
Lets you try out different solutions
Makes it clear what to fix
NoMethodError: undefined method `date’ for nil:NilClass
def render(order) { id: order.id, delivery_date: order.delivery.date } end
def render(order) { id: order.id, delivery_date: order.delivery&.date } end
GET /api/v1/orders?status=delivered • Order 01 • Order 02 • Order
03
Confidence that bug has been fixed
Continuous Integration Heroku Review Apps Create App Precompile Assets Create/Migrate
Database Launch App Code
But what about actually fixing the bugs?
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
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
Is it really the culprit? Caching Third Party Libraries Recent
Changes User
Push Continuous Integration Deploy Revert Continuous Integration
Record Investigate Fix Now Depends on Urgency/Impact
My Latest Bug
None
None
None
None
Reproduce It Don’t jump to conclusions