Remove duplicate behaviour

Author: sn3p

lib/ex_css_modules/ex_css_modules.ex

@@ -43,7 +43,7 @@ defmodule ExCSSModules do
   def class(definition, classes) do
     definition
     |> class_name(classes)
-    |> class_attribute
+    |> class_attribute()
   end
 
   @doc """
@@ -58,11 +58,9 @@ defmodule ExCSSModules do
     nil
   """
   def class(definition, classes, value) do
-    if value do
-      definition
-      |> class_name(classes)
-      |> class_attribute
-    end
+    definition
+    |> class_name(classes, value)
+    |> class_attribute()
   end
 
   @doc """
@@ -108,12 +106,20 @@ defmodule ExCSSModules do
 
     iex> class_name(%{"hello" => "world", "foo" => "bar"}, [{"hello", true}, {"foo", false}])
     "world"
+
+    iex> class_name(%{"hello" => "world", "foo" => "bar"}, [{"hello", false}])
+    nil
   """
   def class_name(definition, keys) when is_list(keys) do
-    keys
-    |> Enum.map(&class_name(definition, &1))
-    |> Enum.reject(&is_nil/1)
-    |> Enum.join(" ")
+    list = keys
+      |> Enum.map(&class_name(definition, &1))
+      |> Enum.reject(&is_nil/1)
+
+    if Enum.any?(list) do
+      Enum.join(list, " ")
+    else
+      nil
+    end
   end
 
   @doc """
@@ -158,5 +164,6 @@ defmodule ExCSSModules do
     end
   end
 
+  defp class_attribute(nil), do: nil
   defp class_attribute(class), do: HTML.raw(~s(class="#{class}"))
 end

test/ex_css_modules/ex_css_modules_test.exs

@@ -27,11 +27,8 @@ defmodule ExCSSModulesTest do
       ) == {:safe, ~s(class="world")}
     end
 
-    test "returns an empty class attribute for a non existing classname" do
-      assert ExCSSModules.class(
-        %{"hello" => "world"},
-        "foo"
-      ) == {:safe, ~s(class="")}
+    test "returns nil for a non existing classname" do
+      assert ExCSSModules.class(%{"hello" => "world"}, "foo") == nil
     end
   end
 
@@ -93,6 +90,13 @@ defmodule ExCSSModulesTest do
       ) == "world"
     end
 
+    test "returns nil ...." do
+      assert ExCSSModules.class_name(
+        %{"hello" => "world", "foo" => "bar"},
+        [{"hello", false}]
+      ) == nil
+    end
+
     test "defaults to nil" do
       assert ExCSSModules.class_name(%{}, "hello") == nil
     end