ruby--ruby/spec/ruby/core/enumerable/shared/take.rb

describe :enumerable_take, shared: true do
  before :each do
    @values = [4,3,2,1,0,-1]
    @enum = EnumerableSpecs::Numerous.new(*@values)
  end

  it "returns the first count elements if given a count" do
    @enum.send(@method, 2).should == [4, 3]
    @enum.send(@method, 4).should == [4, 3, 2, 1] # See redmine #1686 !
  end

  it "returns an empty array when passed count on an empty array" do
    empty = EnumerableSpecs::Empty.new
    empty.send(@method, 0).should == []
    empty.send(@method, 1).should == []
    empty.send(@method, 2).should == []
  end

  it "returns an empty array when passed count == 0" do
    @enum.send(@method, 0).should == []
  end

  it "returns an array containing the first element when passed count == 1" do
    @enum.send(@method, 1).should == [4]
  end

  it "raises an ArgumentError when count is negative" do
    lambda { @enum.send(@method, -1) }.should raise_error(ArgumentError)
  end

  it "returns the entire array when count > length" do
    @enum.send(@method, 100).should == @values
    @enum.send(@method, 8).should == @values  # See redmine #1686 !
  end

  it "tries to convert the passed argument to an Integer using #to_int" do
    obj = mock('to_int')
    obj.should_receive(:to_int).and_return(3).at_most(:twice) # called twice, no apparent reason. See redmine #1554
    @enum.send(@method, obj).should == [4, 3, 2]
  end

  it "raises a TypeError if the passed argument is not numeric" do
    lambda { @enum.send(@method, nil) }.should raise_error(TypeError)
    lambda { @enum.send(@method, "a") }.should raise_error(TypeError)

    obj = mock("nonnumeric")
    lambda { @enum.send(@method, obj) }.should raise_error(TypeError)
  end

  it "gathers whole arrays as elements when each yields multiple" do
    multi = EnumerableSpecs::YieldsMulti.new
    multi.send(@method, 1).should == [[1, 2]]
  end

  it "consumes only what is needed" do
    thrower = EnumerableSpecs::ThrowingEach.new
    thrower.send(@method, 0).should == []
    counter = EnumerableSpecs::EachCounter.new(1,2,3,4)
    counter.send(@method, 2).should == [1,2]
    counter.times_called.should == 1
    counter.times_yielded.should == 2
  end
end