require_relative '../../spec_helper'
require_relative 'fixtures/classes'

describe 'Enumerable#filter_map' do
  before :each do
    @numerous = EnumerableSpecs::Numerous.new(*(1..8).to_a)
  end

  it 'returns an empty array if there are no elements' do
    EnumerableSpecs::Empty.new.filter_map { true }.should == []
  end

  it 'returns an array with truthy results of passing each element to block' do
    @numerous.filter_map { |i| i * 2 if i.even? }.should == [4, 8, 12, 16]
    @numerous.filter_map { |i| i * 2 }.should == [2, 4, 6, 8, 10, 12, 14, 16]
    @numerous.filter_map { 0 }.should == [0, 0, 0, 0, 0, 0, 0, 0]
    @numerous.filter_map { false }.should == []
    @numerous.filter_map { nil }.should == []
  end

  it 'returns an enumerator when no block given' do
    @numerous.filter_map.should.instance_of?(Enumerator)
  end
end
