RSpec Love

Compartilho 10 dicas para melhorar os seus Specs. Referência: betterspecs.org

Transcript

1. RSpec Love
   @lmarinho
   

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3. RSpec Love
   @lmarinho
   

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5. RSpec Love
   @lmarinho
   

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6. RSpec Love
   @lmarinho
   

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7. RSpec Love
   @lmarinho
   

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8. Code Spec
   

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11. DISCLAIMER:
    É SÓ A MINHA OPINIÃO
    

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13. Use expect
    foo.should eq(bar)
    foo.should_not eq(bar)
    

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14. Use expect
    expect(foo).to eq(bar)
    expect(foo).not_to eq(bar)
    

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15. Use expect
    .should
    class Proxy < BasicObject
    def initialize(target)
    @target = target
    end
    def method_missing(*args, &block)
    @target.__send__(*args, &block)
    end
    ...
    end
    

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17. Use describe
    Referencia estrutura do
    código testado
    

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18. Use describe
    describe MyClass do ...
    describe ‘#method’ do ...
    describe ‘.class_method’ do ...
    

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20. Use context
    Define um estado ou
    entrada no sistema
    

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21. Use context
    context ‘when the user has no
    username’ do ...
    context ‘when the account
    balance is 0.0’ do ...
    

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23. Contexto
    Expectativa
    

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24. Use let
    Let ajuda a definir nomes
    relacionados a contextos
    

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25. Use let
    let(:email) { ‘email@example.com’ }
    

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26. Use let
    let(:email) { ‘email@example.com’ }
    let(:user) { User.new(email: email) }
    context ‘when there is no email’ do
    let(:email) { ‘’ }
    it ‘is invalid’ do
    expect(user).to be_invalid
    end
    end
    

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27. Use let
    Prefira ‘let’ a ‘before’, pois o
    primeiro é lazy-loaded
    

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29. Use subject
    Subject ajuda a evitar
    repetição de referências
    

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30. Use subject
    describe User do
    it ‘has the expected attributes’ do
    user = User.new
    expect(user).to respond_to :name
    expect(user).to respond_to :email
    expect(user).to respond_to :age
    end
    end
    

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31. Use subject
    describe User do
    subject { User.new }
    it { should respond_to :name }
    it { should respond_to :email }
    it { should respond_to :age }
    end
    

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33. Use “skim its”
    Skim milk < 0.3% gordura
    Skim it
    1 expectation
    &
    < 4 LOC
    

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35. Crie métodos
    Métodos ajudam a evitar
    repetições desnecessárias
    

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36. Crie métodos
    it { should_create_report_named('Volume Evolution') }
    it { should_create_report_named('Top Users') }
    it { should_create_report_named('Top Terms') }
    it { should_create_report_named('Gender Report') }
    

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37. Crie métodos
    Métodos também ajudam a
    evitar loops em specs
    

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39. Reuse specs
    É possível reusar specs
    através de shared_examples
    

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40. Reuse specs
    shared_examples ‘a collection’ do
    let(:collection) { described_class.new([7, 2,
    4]) }
    context ‘when initialized with 3 items’ do
    it ‘says it has three items’ do
    expect(collection.size).to eq(3)
    end
    end
    end
    

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41. Reuse specs
    describe Array do
    it_behaves_like ‘a collection’
    end
    describe Set do
    it_behaves_like ‘a collection’
    end
    

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43. Use factories
    As vezes...
    

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44. Use factories
    Pois FactoryGirl é legal!
    

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46. Use mocks?
    Mock-based tests are more coupled to the interfaces in
    your system, while classical tests are more coupled to the
    implementation of an object’s collaborators.
    -- Myron Marston
    

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49. Perguntas?
    

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50. Referências
    betterspecs.org e links
    associados
    

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