core: Description.new, .add and .put accept a Map with convertible RDF terms

lib/rdf/description.ex

@@ -31,6 +31,8 @@ defmodule RDF.Description do
     do: new(subject) |> add(predicate, objects)
   def new(subject, description = %RDF.Description{}),
     do: new(subject) |> add(description)
+  def new(subject, predications = %{}),
+    do: new(subject) |> add(predications)
 
 
   @doc """
@@ -89,6 +91,13 @@ defmodule RDF.Description do
     %RDF.Description{subject: subject, predications: merged_predications}
   end
 
+  def add(description = %RDF.Description{}, predications = %{}) do
+    Enum.reduce predications, description, fn ({predicate, objects}, description) ->
+      add(description, predicate, objects)
+    end
+  end
+
+
   @doc """
   Puts objects to a predicate of a `RDF.Description`, overwriting all existing objects.
 
@@ -126,6 +135,9 @@ defmodule RDF.Description do
       iex> RDF.Description.new({EX.S, EX.P, EX.O1}) |>
       ...>   RDF.Description.put(RDF.Description.new(EX.S, EX.P, [EX.O1, EX.O2]))
       RDF.Description.new([{EX.S, EX.P, EX.O1}, {EX.S, EX.P, EX.O2}])
+      iex> RDF.Description.new([{EX.S, EX.P1, EX.O1}, {EX.S, EX.P2, EX.O2}]) |>
+      ...>   RDF.Description.put(%{EX.P2 => [EX.O3, EX.O4]})
+      RDF.Description.new([{EX.S, EX.P1, EX.O1}, {EX.S, EX.P2, EX.O3}, {EX.S, EX.P2, EX.O4}])
   """
   def put(description, statements)
 
@@ -161,6 +173,13 @@ defmodule RDF.Description do
     %RDF.Description{subject: subject, predications: merged_predications}
   end
 
+  def put(description = %RDF.Description{}, predications = %{}) do
+    Enum.reduce predications, description, fn ({predicate, objects}, description) ->
+      put(description, predicate, objects)
+    end
+  end
+
+
 
   @doc """
   Fetches the objects for the given predicate of a Description.

test/unit/description_test.exs

@@ -11,6 +11,7 @@ defmodule RDF.DescriptionTest do
 
 
   def description, do: Description.new(EX.Subject)
+  def description(content), do: Description.add(description, content)
   def description_of_subject(%Description{subject: subject}, subject), do: true
   def description_of_subject(_, _), do: false
   def empty_description(%Description{predications: predications}) do
@@ -73,6 +74,13 @@ defmodule RDF.DescriptionTest do
     assert description_includes_predication(desc2, {EX.predicate, uri(EX.Object)})
   end
 
+  test "creating a description from a map with convertible RDF term" do
+    desc = Description.new(EX.Subject, %{EX.Predicate => EX.Object})
+    assert description_of_subject(desc, uri(EX.Subject))
+    assert description_includes_predication(desc, {uri(EX.Predicate), uri(EX.Object)})
+  end
+
+
   describe "add" do
     test "a predicate-object-pair of proper RDF terms" do
       assert Description.add(description, EX.predicate, uri(EX.Object))
@@ -146,10 +154,7 @@ defmodule RDF.DescriptionTest do
 
 
     test "another description" do
-      desc =
-        description
-        |> Description.add([{EX.predicate1, EX.Object1},
-                            {EX.predicate2, EX.Object2}])
+      desc = description([{EX.predicate1, EX.Object1}, {EX.predicate2, EX.Object2}])
         |> Description.add(Description.new({EX.Other, EX.predicate3, EX.Object3}))
 
       assert description_of_subject(desc, uri(EX.Subject))
@@ -164,6 +169,36 @@ defmodule RDF.DescriptionTest do
       assert description_includes_predication(desc, {EX.predicate1, uri(EX.Object4)})
     end
 
+    test "a map of predications with convertible RDF terms" do
+      desc = description([{EX.predicate1, EX.Object1}, {EX.predicate2, EX.Object2}])
+        |> Description.add(%{EX.predicate3 => EX.Object3})
+
+      assert description_of_subject(desc, uri(EX.Subject))
+      assert description_includes_predication(desc, {EX.predicate1, uri(EX.Object1)})
+      assert description_includes_predication(desc, {EX.predicate2, uri(EX.Object2)})
+      assert description_includes_predication(desc, {EX.predicate3, uri(EX.Object3)})
+
+      desc = Description.add(desc, %{EX.predicate1 => EX.Object1,
+                                     EX.predicate2 => [EX.Object2, 42],
+                                     EX.predicate3 => [bnode(:foo)]})
+      assert Description.count(desc) == 5
+      assert description_includes_predication(desc, {EX.predicate1, uri(EX.Object1)})
+      assert description_includes_predication(desc, {EX.predicate2, uri(EX.Object2)})
+      assert description_includes_predication(desc, {EX.predicate2, literal(42)})
+      assert description_includes_predication(desc, {EX.predicate3, uri(EX.Object3)})
+      assert description_includes_predication(desc, {EX.predicate3, bnode(:foo)})
+    end
+
+    test "a map of predications with inconvertible RDF terms" do
+      assert_raise RDF.InvalidURIError, fn ->
+        Description.add(description, %{"not a URI" => uri(EX.Object)})
+      end
+
+      assert_raise RDF.InvalidLiteralError, fn ->
+        Description.add(description, %{EX.prop => self})
+      end
+    end
+
     test "duplicates are ignored" do
       desc = Description.add(description, {EX.predicate, EX.Object})
       assert Description.add(desc, {EX.predicate, EX.Object}) == desc