require_relative '../../spec_helper'
require_relative 'fixtures/classes'
describe "Enumerable#chunk" do
before do
ScratchPad.record []
end
it "returns an Enumerator if called without a block" do
chunk = EnumerableSpecs::Numerous.new(1, 2, 3, 1, 2).chunk
chunk.should be_an_instance_of(Enumerator)
result = chunk.with_index {|elt, i| elt - i }.to_a
result.should == [[1, [1, 2, 3]], [-2, [1, 2]]]
end
it "returns an Enumerator if given a block" do
EnumerableSpecs::Numerous.new.chunk {}.should be_an_instance_of(Enumerator)
end
it "yields the current element and the current chunk to the block" do
e = EnumerableSpecs::Numerous.new(1, 2, 3)
e.chunk { |x| ScratchPad << x }.to_a
ScratchPad.recorded.should == [1, 2, 3]
end
it "returns elements of the Enumerable in an Array of Arrays, [v, ary], where 'ary' contains the consecutive elements for which the block returned the value 'v'" do
e = EnumerableSpecs::Numerous.new(1, 2, 3, 2, 3, 2, 1)
result = e.chunk { |x| x < 3 && 1 || 0 }.to_a
result.should == [[1, [1, 2]], [0, [3]], [1, [2]], [0, [3]], [1, [2, 1]]]
end
it "returns elements for which the block returns :_alone in separate Arrays" do
e = EnumerableSpecs::Numerous.new(1, 2, 3, 2, 1)
result = e.chunk { |x| x < 2 && :_alone }.to_a
result.should == [[:_alone, [1]], [false, [2, 3, 2]], [:_alone, [1]]]
end
it "does not return elements for which the block returns :_separator" do
e = EnumerableSpecs::Numerous.new(1, 2, 3, 3, 2, 1)
result = e.chunk { |x| x == 2 ? :_separator : 1 }.to_a
result.should == [[1, [1]], [1, [3, 3]], [1, [1]]]
end
it "does not return elements for which the block returns nil" do
e = EnumerableSpecs::Numerous.new(1, 2, 3, 2, 1)
result = e.chunk { |x| x == 2 ? nil : 1 }.to_a
result.should == [[1, [1]], [1, [3]], [1, [1]]]
end
it "raises a RuntimeError if the block returns a Symbol starting with an underscore other than :_alone or :_separator" do
e = EnumerableSpecs::Numerous.new(1, 2, 3, 2, 1)
-> { e.chunk { |x| :_arbitrary }.to_a }.should raise_error(RuntimeError)
end
it "does not accept arguments" do
e = EnumerableSpecs::Numerous.new(1, 2, 3)
-> {
e.chunk(1) {}
}.should raise_error(ArgumentError)
end
it 'returned Enumerator size returns nil' do
e = EnumerableSpecs::NumerousWithSize.new(1, 2, 3, 2, 1)
enum = e.chunk { |x| true }
enum.size.should == nil
end
end
>