1 files changed, 39 insertions, 0 deletions
diff --git a/activemodel/test/cases/type/registry_test.rb b/activemodel/test/cases/type/registry_test.rb
new file mode 100644
index 0000000000..2a48998a62
--- /dev/null
+++ b/activemodel/test/cases/type/registry_test.rb
@@ -0,0 +1,39 @@
+require "cases/helper"
+require "active_model/type"
+
+module ActiveModel
+  class RegistryTest < ActiveModel::TestCase
+    test "a class can be registered for a symbol" do
+      registry = Type::Registry.new
+      registry.register(:foo, ::String)
+      registry.register(:bar, ::Array)
+
+      assert_equal "", registry.lookup(:foo)
+      assert_equal [], registry.lookup(:bar)
+    end
+
+    test "a block can be registered" do
+      registry = Type::Registry.new
+      registry.register(:foo) do |*args|
+        [*args, "block for foo"]
+      end
+      registry.register(:bar) do |*args|
+        [*args, "block for bar"]
+      end
+
+      assert_equal [:foo, 1, "block for foo"], registry.lookup(:foo, 1)
+      assert_equal [:foo, 2, "block for foo"], registry.lookup(:foo, 2)
+      assert_equal [:bar, 1, 2, 3, "block for bar"], registry.lookup(:bar, 1, 2, 3)
+    end
+
+    test "a reasonable error is given when no type is found" do
+      registry = Type::Registry.new
+
+      e = assert_raises(ArgumentError) do
+        registry.lookup(:foo)
+      end
+
+      assert_equal "Unknown type :foo", e.message
+    end
+  end
+end