require "./spec_helper"

describe HeapHash do
  describe "#[]" do
    hh = HeapHash(String, Int32).new

    it "correctly assigns new keys" do
      hh["a"] = 5
      hh["b"] = 3
      hh["c"] = 10
      hh["a"].should eq(5)
      hh["b"].should eq(3)
      hh["c"].should eq(10)
      hh.size.should eq(3)
    end

    it "correctly updates the value of a key" do
      hh["a"] = 0
      hh["a"].should eq(0)
      hh.size.should eq(3)
    end

    it "returns nil for non-existent keys" do
      hh["?"]?.should be_nil
    end

    it "throws for non-existent keys" do
      expect_raises(KeyError) do
        hh["?"]
      end
    end
  end

  describe "#pop" do
    it "pops keys in the right oder" do
      hh = HeapHash(String, Int32).new
      expect_raises(IndexError) do
        hh.pop
      end

      hh["last"] = 1
      hh["first"] = 10
      hh["medium"] = 5

      hh.pop.should eq({"first", 10})
      hh.pop.should eq({"medium", 5})
      hh.pop.should eq({"last", 1})
    end
  end

  describe "#delete" do
    it "doesn't break the heap property" do
      hh = HeapHash(String, Int32).new

      hh["last"] = 1
      hh["first"] = 10
      hh["medium"] = 5
      
      popped = hh.delete "last"
      popped.should eq({"last", 1})
      hh.pop.should eq({"first", 10})
      hh.pop.should eq({"medium", 5})
    end
  end
end