search_insert_position_test.rb

require_relative "../../test_helper"
require_relative "search_insert_position"

describe SearchInsertPosition do
  describe "edge cases" do
    it "should insert item into an empty array" do
      actual = SearchInsertPosition.run([], target: 0)
      expect(actual).must_equal 0
    end
  end

  describe "regular cases" do
    it "should insert before existing target item" do
      actual = SearchInsertPosition.run([1, 3, 5, 6], target: 3)
      expect(actual).must_equal 1
    end

    it "should insert at 0th index when target < arr[0]" do
      actual = SearchInsertPosition.run([1, 3, 5, 6], target: 0)
      expect(actual).must_equal 0
    end

    it "should insert at 1st index" do
      actual = SearchInsertPosition.run([1, 3, 5, 6], target: 2)
      expect(actual).must_equal 1
    end

    it "should insert at 2nd index" do
      actual = SearchInsertPosition.run([1, 3, 5, 6], target: 4)
      expect(actual).must_equal 2
    end

    it "should insert at 3rd index" do
      actual = SearchInsertPosition.run([1, 3, 5, 7], target: 6)
      expect(actual).must_equal 3
    end

    it "should insert at last index" do
      actual = SearchInsertPosition.run([1, 3, 5, 7], target: 100)
      expect(actual).must_equal 4
    end
  end
end