我如何測試rspec mocks的有序和x次？

Question

我有一個遞歸方法，我需要測試方法調用的順序，以及它們被調用的次數。我遇到的問題是，這些方法調用交替。例如..

it 'call methods in order' do 
    expect(@instance).to have_received(:foo).ordered 
    expect(@instance).to have_received(:bar).ordered 
    expect(@instance).to have_received(:foo).ordered 
    expect(@instance).to have_received(:bar).ordered 
    expect(@instance).to have_received(:foo).ordered 
    expect(@instance).to have_received(:bar).ordered 
end 

失敗的原因與

expected: 1 time with any arguments 
received: 3 times with any arguments 

foo和bar被稱爲3次是正確的，但我怎麼測試他們交流？

Answer 1

像這樣的東西應該工作：

it 'call methods in order' do 
    @method_calls = [] 

    allow(@instance).to receive(:foo) do 
    @method_calls << :foo 
    end 

    allow(@instance).to receive(:bar) do 
    @method_calls << :bar 
    end 

    ... 

    expect(@method_calls).to eq([:foo, :bar, :foo, :bar, :foo, :bar])  
end 

這裏有一個最小的測試，我想這說明了這一點充分：

require "rspec" 

class MyClass 
    def bar 
    end 

    def foo 
    end 

    def foobar 
    foo 
    bar 
    foo 
    bar 
    foo 
    bar 
    end 
end 

describe "Foo" do 
    describe "#foobar" do 
    let(:instance) { MyClass.new } 

    it "alternately calls foo/bar" do 
     @method_calls = [] 

     allow(instance).to receive(:foo) do 
     @method_calls << :foo 
     end 

     allow(instance).to receive(:bar) do 
     @method_calls << :bar 
     end 

     instance.foobar 

     expect(@method_calls).to eq([:foo, :bar, :foo, :bar, :foo, :bar]) 
    end 
    end 
end 

運行此規範通過，但刪除（說）的方法之一調用foobar方法會導致此錯誤：

F 

Failures: 

    1) Foo #foobar alternately calls foo/bar 
    Failure/Error: expect(@method_calls).to eq([:foo, :bar, :foo, :bar, :foo, :bar]) 

     expected: [:foo, :bar, :foo, :bar, :foo, :bar] 
      got: [:bar, :foo, :bar, :foo, :bar] 

     (compared using ==) 

     Diff: 
     @@ -1,2 +1,2 @@ 
     -[:foo, :bar, :foo, :bar, :foo, :bar] 
     +[:bar, :foo, :bar, :foo, :bar] 
    # ./rspec_test.rb:38:in `block (3 levels) in <top (required)>' 

Finished in 0.01517 seconds (files took 0.07714 seconds to load) 
1 example, 1 failure 

Failed examples: 

rspec ./rspec_test.rb:25 # Foo #foobar alternately calls foo/bar 

Hope這就說得通了。

Answer 2

您應該封裝方法的遞歸部分，存根其他部分，然後通過黑盒方法（即輸入 - >輸出）測試該方法。