Merge pull request #323 from VirtusLab/issue-120

fix conversion of !!null to non-optional types
VirtusLab · Jul 21, 2024 · a58465a · a58465a
2 parents a3aa5b9 + c4ef564
commit a58465a
Show file tree

Hide file tree

Showing 2 changed files with 34 additions and 7 deletions.
diff --git a/core/shared/src/main/scala/org/virtuslab/yaml/YamlDecoder.scala b/core/shared/src/main/scala/org/virtuslab/yaml/YamlDecoder.scala
@@ -67,11 +67,19 @@ object YamlDecoder extends YamlDecoderCompanionCrossCompat {
       override def construct(
           node: Node
       )(implicit settings: LoadSettings = LoadSettings.empty): Either[ConstructError, T] =
-        if (pf.isDefinedAt(node)) pf(node)
+        if (node.tag == Tag.nullTag)
+          Left(
+            ConstructError.from(
+              s"""|Could't construct ${classTag.runtimeClass.getName} from null (${node.tag.value})
+                  |${node.pos.map(_.errorMsg).getOrElse("")}
+                  |""".stripMargin
+            )
+          )
+        else if (pf.isDefinedAt(node)) pf(node)
         else
           Left(
             ConstructError.from(
-              s"""|Could't construct ${classTag.runtimeClass.getName} from ${node.tag}
+              s"""|Could't construct ${classTag.runtimeClass.getName} from ${node.tag.value}
                   |${node.pos.map(_.errorMsg).getOrElse("")}
                   |""".stripMargin
             )
@@ -198,11 +206,14 @@ object YamlDecoder extends YamlDecoderCompanionCrossCompat {
     }
   }
 
-  implicit def forOption[T](implicit c: YamlDecoder[T]): YamlDecoder[Option[T]] = YamlDecoder.from {
-    node =>
-      if (node.tag == Tag.nullTag) Right(None)
-      else c.construct(node).map(Option(_))
-  }
+  implicit def forOption[T](implicit c: YamlDecoder[T]): YamlDecoder[Option[T]] =
+    new YamlDecoder[Option[T]] {
+      override def construct(
+          node: Node
+      )(implicit settings: LoadSettings): Either[ConstructError, Option[T]] =
+        if (node.tag == Tag.nullTag) Right(None)
+        else c.construct(node).map(Option(_))
+    }
 
   private def constructFromNodes[T](nodes: Seq[Node])(implicit
       c: YamlDecoder[T]

diff --git a/core/shared/src/test/scala-3/org/virtuslab/yaml/decoder/DecoderSuite.scala b/core/shared/src/test/scala-3/org/virtuslab/yaml/decoder/DecoderSuite.scala
@@ -486,3 +486,19 @@ class DecoderSuite extends munit.FunSuite:
       case Right(value) =>
         assertEquals(value, Map("value" -> 0.018256052173961423))
   }
+
+  test("issue 120 - fail conversion of !!null to non-optional types") {
+    case class Foo(key1: Int, key2: Int) derives YamlDecoder
+
+    val yaml =
+      """|key1: 1
+         |key2: !!null
+         |""".stripMargin
+
+    val bar = yaml.as[Foo]
+
+    bar match
+      case Left(error: YamlError) =>
+        assert(error.msg.contains("Could't construct int from null (tag:yaml.org,2002:null)"))
+      case Right(data) => fail(s"expected failure, but got: $data")
+  }