Add tests for combining multiple registries and registry-less types

test/registry.js

@@ -217,5 +217,49 @@ describe("registry", () => {
 				registry.createTrait("DuplicateTrait", {});
 			}).to.throw("A trait named DuplicateTrait already exists in this registry");
 		});
+
+		it("should allow using types from different registries (as well as registry-less types) with one another", () => {
+			let registryOne = dm.createRegistry();
+			let registryTwo = dm.createRegistry();
+
+			let Item = dm.createType("Item", {
+				value: dm.string()
+			});
+
+			let ItemOne = registryOne.createType("Item", {
+				two: registryTwo.type("Item")
+			});
+
+			let ItemTwo = registryTwo.createType("Item", {
+				item: Item
+			});
+
+			let zero = Item({
+				value: "foo"
+			});
+
+			let two = ItemTwo({
+				item: zero
+			});
+
+			let one = ItemOne({
+				two: two
+			});
+
+			expect(one.two.item.value).to.equal("foo");
+
+			expect(() => {
+				ItemOne({
+					two: ItemOne({
+						two: ItemTwo({
+							item: Item({
+								value: "bar"
+							})
+						})
+					})
+				});
+			}).to.throw("Expected an instance of Item, got an instance of Item instead");
+			/* TODO: Clarify the error message when the display name of two types is the same. */
+		});
 	});
 });