require File.expand_path('../../../spec_helper', __FILE__)
require File.expand_path('../fixtures/common', __FILE__)
describe "Enumerator#feed" do
before :each do
ScratchPad.record []
@enum = EnumeratorSpecs::Feed.new.to_enum(:each)
end
it "sets the future return value of yield if called before advancing the iterator" do
@enum.feed :a
@enum.next
@enum.next
@enum.next
ScratchPad.recorded.should == [:a, nil]
end
it "causes yield to return the value if called during iteration" do
@enum.next
@enum.feed :a
@enum.next
@enum.next
ScratchPad.recorded.should == [:a, nil]
end
it "can be called for each iteration" do
@enum.next
@enum.feed :a
@enum.next
@enum.feed :b
@enum.next
ScratchPad.recorded.should == [:a, :b]
end
it "returns nil" do
@enum.feed(:a).should be_nil
end
it "raises a TypeError if called more than once without advancing the enumerator" do
@enum.feed :a
@enum.next
lambda { @enum.feed :b }.should raise_error(TypeError)
end
it "sets the return value of Yielder#yield" do
enum = Enumerator.new { |y| ScratchPad << y.yield }
enum.next
enum.feed :a
lambda { enum.next }.should raise_error(StopIteration)
ScratchPad.recorded.should == [:a]
end
end