diy-pager-api-results.rb

require "minitest/autorun"
require "minitest/spec"

class Pager
  def initialize(results:, rows_per_page:)
    @results = results
    @rows_per_page = rows_per_page
  end

  def total_pages
    (@results.count/@rows_per_page.to_f).ceil
  end
end

describe Pager do
  describe "#total_pages" do
    it "rounds up to the next whole number" do
      # This will give us an Array with elements 1-33, i.e. [1, 2, 3, ...]
      results = (1..33).to_a

      pager = Pager.new(results: results, rows_per_page: 10)

      assert_equal pager.total_pages, 4
    end

    it "returns 1 when there are less than rows_per_page" do
      results = (1..5).to_a

      pager = Pager.new(results: results, rows_per_page: 10)

      assert_equal pager.total_pages, 1
    end

    it "returns 0 when there are 0 rows" do
      results = []

      pager = Pager.new(results: results, rows_per_page: 10)

      assert_equal pager.total_pages, 0
    end
  end
end