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Project: RSpec Mocks 2.9

Publisher: RSpec

stub on any instance of a class

Use any_instance.stub on a class to tell any instance of that class to
return a value (or values) in response to a given message. If no instance
receives the message, nothing happens.

Messages can be stubbed on any class, including those in Ruby's core library.

Scenarios
  1. any_instance stub with a single return value
  2. any_instance stub with a hash
  3. any_instance stub with specific arguments matchers
  4. any_instance unstub
  5. any_instance unstub
  6. stub a chain of methods an any instance
any_instance stub with a single return value
Given
a file named "example_spec.rb" with: 
describe "any_instance.stub" do
  it "returns the specified value on any instance of the class" do
    Object.any_instance.stub(:foo).and_return(:return_value)

    o = Object.new
    o.foo.should eq(:return_value)
  end
end
When
I run rspec example_spec.rb
Then
the examples should all pass
any_instance stub with a hash
Given
a file named "example_spec.rb" with: 
describe "any_instance.stub" do
  context "with a hash" do
    it "returns the hash values on any instance of the class" do
      Object.any_instance.stub(:foo => 'foo', :bar => 'bar')

      o = Object.new
      o.foo.should eq('foo')
      o.bar.should eq('bar')
    end
  end
end
When
I run rspec example_spec.rb
Then
the examples should all pass
any_instance stub with specific arguments matchers
Given
a file named "example_spec.rb" with: 
describe "any_instance.stub" do
  context "with arguments" do
    it "returns the stubbed value when arguments match" do
      Object.any_instance.stub(:foo).with(:param_one, :param_two).and_return(:result_one)
      Object.any_instance.stub(:foo).with(:param_three, :param_four).and_return(:result_two)
    
      o = Object.new
      o.foo(:param_one, :param_two).should eq(:result_one)
      o.foo(:param_three, :param_four).should eq(:result_two)
    end
  end
end
When
I run rspec example_spec.rb
Then
the examples should all pass
any_instance unstub
Given
a file named "example_spec.rb" with: 
describe "any_instance.unstub" do
  it "unstubs a stubbed method" do
    class Object
      def foo
        :foo
      end
    end
    
    Object.any_instance.stub(:foo)
    Object.any_instance.unstub(:foo)

    Object.new.foo.should eq(:foo)
  end
end
When
I run rspec example_spec.rb
Then
the examples should all pass
any_instance unstub
Given
a file named "example_spec.rb" with: 
describe "any_instance.unstub" do
  context "with both an expectation and a stub already set" do
    it "only removes the stub" do
      class Object
        def foo
          :foo
        end
      end
      Object.any_instance.should_receive(:foo).and_return(:bar)
      Object.any_instance.stub(:foo)
      Object.any_instance.unstub(:foo)
      
      Object.new.foo.should eq(:bar)
    end
  end
end
When
I run rspec example_spec.rb
Then
the examples should all pass
stub a chain of methods an any instance
Given
a file named "stub_chain_spec.rb" with: 
describe "stubbing a chain of methods" do
  context "given symbols representing methods" do
    it "returns the correct value" do
      Object.any_instance.stub_chain(:one, :two, :three).and_return(:four)
      Object.new.one.two.three.should eq(:four)
    end
  end

  context "given a hash at the end" do
    it "returns the correct value" do
      Object.any_instance.stub_chain(:one, :two, :three => :four)
      Object.new.one.two.three.should eq(:four)
    end
  end

  context "given a string of methods separated by dots" do
    it "returns the correct value" do
      Object.any_instance.stub_chain("one.two.three").and_return(:four)
      Object.new.one.two.three.should eq(:four)
    end
  end
end
When
I run rspec stub_chain_spec.rb
Then
the examples should all pass

Last published about 4 years ago by dchelimsky.