Add Sequence.next/1 for quickly creating sequences

Closes #66

lib/ex_machina.ex

@@ -61,7 +61,7 @@ defmodule ExMachina do
     quote do
       @before_compile unquote(__MODULE__)
 
-      import ExMachina, only: [sequence: 2, factory: 2]
+      import ExMachina, only: [sequence: 1, sequence: 2, factory: 2]
 
       def build(factory_name, attrs \\ %{}) do
         ExMachina.build(__MODULE__, factory_name, attrs)
@@ -108,6 +108,22 @@ defmodule ExMachina do
     """
   end
 
+  @doc """
+  Shortcut for creating unique values. Similar to sequence/2
+
+  For more customization of the generated string, see ExMachina.sequence/2
+
+  ## Examples
+
+      def factory(:comment) do
+        %{
+          # Will generate "Comment Title 0" then "Comment Title 1", etc.
+          title: sequence("Comment Title")
+        }
+      end
+  """
+  def sequence(name), do: ExMachina.Sequence.next(name)
+
   @doc """
   Create sequences for generating unique values
 

lib/ex_machina/sequence.ex

@@ -3,6 +3,12 @@ defmodule ExMachina.Sequence do
     Agent.start_link(fn -> HashDict.new end, name: __MODULE__)
   end
 
+  def next(sequence_name) do
+    next sequence_name, fn(n)->
+      sequence_name <> " " <> to_string(n)
+    end
+  end
+
   def next(sequence_name, formatter) do
     Agent.get_and_update(__MODULE__, fn(sequences) ->
       current_value = HashDict.get(sequences, sequence_name, 0)

test/ex_machina/sequence_test.exs

@@ -18,4 +18,9 @@ defmodule ExMachina.SequenceTest do
     assert 0 == Sequence.next(:month, &(&1))
     assert 1 == Sequence.next(:month, &(&1))
   end
+
+  test "let's you quickly create sequences" do
+    assert "Comment Body 0" == Sequence.next("Comment Body")
+    assert "Comment Body 1" == Sequence.next("Comment Body")
+  end
 end

test/ex_machina_test.exs

@@ -18,6 +18,12 @@ defmodule ExMachinaTest do
       }
     end
 
+    def factory(:article) do
+      %{
+        title: sequence("Post Title")
+      }
+    end
+
     def save_record(record) do
       send self, {:custom_save, record}
       record
@@ -37,6 +43,11 @@ defmodule ExMachinaTest do
     assert "me-1@foo.com" == Factory.build(:email).email
   end
 
+  test "sequence/1 shortcut for creating sequences" do
+    assert "Post Title 0" == Factory.build(:article).title
+    assert "Post Title 1" == Factory.build(:article).title
+  end
+
   test "raises a helpful error if the factory is not defined" do
     assert_raise ExMachina.UndefinedFactory, fn ->
       Factory.build(:foo)