defmodule RDF.QuadTest do
  use RDF.Test.Case

  doctest RDF.Quad

  alias RDF.Quad

  describe "values/1" do
    test "with a valid RDF.Quad" do
      assert Quad.values({~I<http://example.com/S>, ~I<http://example.com/p>, XSD.integer(42), ~I<http://example.com/Graph>})
             == {"http://example.com/S", "http://example.com/p", 42, "http://example.com/Graph"}
      assert Quad.values({~I<http://example.com/S>, ~I<http://example.com/p>, XSD.integer(42), nil})
             == {"http://example.com/S", "http://example.com/p", 42, nil}
    end

    test "with an invalid RDF.Quad" do
      refute Quad.values({~I<http://example.com/S>, ~I<http://example.com/p>})
      refute Quad.values({self(), self(), self(), self()})
    end
  end

  test "values/2" do
    assert {~I<http://example.com/S>, ~I<http://example.com/p>, XSD.integer(42), ~I<http://example.com/Graph>}
           |> Quad.values(fn
             {:subject, subject} -> subject |> to_string() |> String.last() |> String.to_atom()
             {:predicate, _}     -> :p
             {:object, object}   -> object |> RDF.Term.value() |> Kernel.+(1)
             {:graph_name, _}    -> nil
           end)
           == {:S, :p, 43, nil}
  end

end