Add test of SupportedCtapOptions serialization stability

This test will be needed later for a more focused view on why the sibling test
of `MetadataBLOBPayload` serialization stability begins to fail.

Author: emlun

webauthn-server-attestation/src/test/scala/com/yubico/fido/metadata/MetadataBlobSpec.scala

@@ -1,11 +1,17 @@
 package com.yubico.fido.metadata
 
+import com.yubico.fido.metadata.Generators.arbitrarySupportedCtapOptions
 import com.yubico.internal.util.JacksonCodecs
 import com.yubico.webauthn.data.ByteArray
+import org.scalacheck.Arbitrary
+import org.scalacheck.Gen
 import org.scalatest.funspec.AnyFunSpec
 import org.scalatest.matchers.should.Matchers
 import org.scalatestplus.scalacheck.ScalaCheckDrivenPropertyChecks
 
+import scala.jdk.CollectionConverters.SetHasAsScala
+import scala.jdk.OptionConverters.RichOptional
+
 class MetadataBlobSpec
     extends AnyFunSpec
     with Matchers
@@ -50,4 +56,34 @@ class MetadataBlobSpec
     }
   }
 
+  describe("SupportedCtapOptions") {
+    it(
+      "are structurally identical after multiple (de)serialization round-trips."
+    ) {
+      val json = JacksonCodecs.json()
+      val blob = json
+        .readValue(
+          ByteArray
+            .fromBase64Url(FidoMds3Examples.BlobPayloadBase64url)
+            .getBytes,
+          classOf[MetadataBLOBPayload],
+        )
+      val blobOptions = blob.getEntries.asScala
+        .flatMap(entry => entry.getMetadataStatement.toScala)
+        .flatMap(statement => statement.getAuthenticatorGetInfo.toScala)
+        .flatMap(info => info.getOptions.toScala)
+      forAll(Gen.oneOf(Arbitrary.arbitrary, Gen.oneOf(blobOptions))) {
+        (options1: SupportedCtapOptions) =>
+          val encoded1 = json.writeValueAsBytes(options1)
+          val options2 = json.readValue(encoded1, classOf[SupportedCtapOptions])
+          val encoded2 = json.writeValueAsBytes(options2)
+          val options3 = json.readValue(encoded2, classOf[SupportedCtapOptions])
+
+          options2 should not be null
+          options2 should equal(options1)
+          options3 should not be null
+          options3 should equal(options1)
+      }
+    }
+  }
 }