print_combos_test.rb

require_relative "../../test_helper"
require_relative "print_combos"

describe PrintCombos do
  describe "edge cases" do
    it "should print an empty string given an empty array" do
      expected = ""
      subject = -> { PrintCombos.run([], Array.new(0), 0, 0) }
      expect(subject).must_output expected
    end

    it "should print an empty string when x > arr.length" do
      expected = ""
      subject = -> { PrintCombos.run([1, 2, 3], Array.new(4), 0, 0) }
      expect(subject).must_output expected
    end
  end

  describe "base cases" do
    it "should print results when x = 1, arr.length == 1" do
      expected = print_results [1]
      subject = -> { PrintCombos.run([1], Array.new(1), 0, 0) }
      expect(subject).must_output expected
    end

    it "should print results when x = 1, arr.length == 2" do
      expected = print_results [1], [2]
      subject = -> { PrintCombos.run([1, 2], Array.new(1), 0, 0) }
      expect(subject).must_output expected
    end
  end

  describe "regular cases" do
    it "should print results when = 2, arr.length == 3" do
      expected = print_results [1, 2], [1, 3], [2, 3]
      subject = -> { PrintCombos.run([1, 2, 3], Array.new(2), 0, 0) }
      expect(subject).must_output expected
    end

    it "should print results when x = 3, arr.length == 4" do
      expected = print_results [1, 2, 3], [1, 2, 4], [1, 3, 4], [2, 3, 4]
      subject = -> { PrintCombos.run([1, 2, 3, 4], Array.new(3), 0, 0) }
      expect(subject).must_output expected
    end

    it "should print results when x = 3, arr.length == 3" do
      expected = print_results [1, 2, 3]
      subject = -> { PrintCombos.run([1, 2, 3], Array.new(3), 0, 0) }
      expect(subject).must_output expected
    end
  end
end