1 files changed, 62 insertions, 0 deletions
diff --git a/src/test/scala/firrtl/JsonProtocolSpec.scala b/src/test/scala/firrtl/JsonProtocolSpec.scala
new file mode 100644
index 00000000..955abdc0
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+++ b/src/test/scala/firrtl/JsonProtocolSpec.scala
@@ -0,0 +1,62 @@
+// See LICENSE for license details.
+
+package firrtlTests
+
+import org.scalatest.FlatSpec
+import org.json4s._
+import org.json4s.native.JsonMethods._
+
+import firrtl.annotations.{NoTargetAnnotation, JsonProtocol, InvalidAnnotationJSONException, HasSerializationHints, Annotation}
+
+object JsonProtocolTestClasses {
+  trait Parent
+
+  case class ChildA(foo: Int) extends Parent
+  case class ChildB(bar: String) extends Parent
+  case class PolymorphicParameterAnnotation(param: Parent) extends NoTargetAnnotation
+  case class PolymorphicParameterAnnotationWithTypeHints(param: Parent) extends NoTargetAnnotation with HasSerializationHints {
+    def typeHints = Seq(param.getClass)
+  }
+
+  case class TypeParameterizedAnnotation[T](param: T) extends NoTargetAnnotation
+  case class TypeParameterizedAnnotationWithTypeHints[T](param: T) extends NoTargetAnnotation with HasSerializationHints {
+    def typeHints = Seq(param.getClass)
+  }
+}
+
+import JsonProtocolTestClasses._
+
+class JsonProtocolSpec extends FlatSpec {
+  def serializeAndDeserialize(anno: Annotation): Annotation = {
+    val serializedAnno = JsonProtocol.serialize(Seq(anno))
+    JsonProtocol.deserialize(serializedAnno).head
+  }
+
+  "Annotations with polymorphic parameters" should "not serialize and deserialize without type hints" in {
+    val anno = PolymorphicParameterAnnotation(ChildA(1))
+    assertThrows[InvalidAnnotationJSONException] {
+      serializeAndDeserialize(anno)
+    }
+  }
+
+  it should "serialize and deserialize with type hints" in {
+    val anno = PolymorphicParameterAnnotationWithTypeHints(ChildA(1))
+    val deserAnno = serializeAndDeserialize(anno)
+    assert(anno == deserAnno)
+
+    val anno2 = PolymorphicParameterAnnotationWithTypeHints(ChildB("Test"))
+    val deserAnno2 = serializeAndDeserialize(anno2)
+    assert(anno2 == deserAnno2)
+  }
+
+  "Annotations with non-primitive type parameters" should "not serialize and deserialize without type hints" in {
+    val anno = TypeParameterizedAnnotation(ChildA(1))
+    val deserAnno = serializeAndDeserialize(anno)
+    assert (anno != deserAnno)
+  }
+  it should "serialize and deserialize with type hints" in {
+    val anno = TypeParameterizedAnnotationWithTypeHints(ChildA(1))
+    val deserAnno = serializeAndDeserialize(anno)
+    assert (anno == deserAnno)
+  }
+}