extract isAssignable

components-api/src/main/scala/pl/touk/nussknacker/engine/api/typed/CanBeSubclassDeterminer.scala

@@ -4,6 +4,7 @@ import cats.data.Validated._
 import cats.data.{NonEmptyList, ValidatedNel}
 import cats.implicits.{catsSyntaxValidatedId, _}
 import org.apache.commons.lang3.ClassUtils
+import pl.touk.nussknacker.engine.api.typed.CanBeSubclassDeterminer.isAssignable
 import pl.touk.nussknacker.engine.api.typed.supertype.NumberTypesPromotionStrategy.AllNumbers
 import pl.touk.nussknacker.engine.api.typed.typing._
 
@@ -136,7 +137,11 @@ trait CanBeSubclassDeterminer {
         (),
         f"${givenClass.display} and ${superclassCandidate.display} are not the same"
       ) orElse
-        isAssignable(givenClass.klass, superclassCandidate.klass)
+        condNel(
+          isAssignable(givenClass.klass, superclassCandidate.klass),
+          (),
+          s"${givenClass.klass} is not assignable from ${superclassCandidate.klass}"
+        )
 
     val canBeSubclass = equalClassesOrCanAssign andThen (_ => typeParametersMatches(givenClass, superclassCandidate))
     canBeSubclass orElse canBeConvertedTo(givenType, superclassCandidate)
@@ -207,18 +212,19 @@ trait CanBeSubclassDeterminer {
     condNel(TypeConversionHandler.canBeConvertedTo(givenType, superclassCandidate), (), errMsgPrefix)
   }
 
+}
+
+object CanBeSubclassDeterminer extends CanBeSubclassDeterminer {
+
   // we use explicit autoboxing = true flag, as ClassUtils in commons-lang3:3.3 (used in Flink) cannot handle JDK 11...
-  private def isAssignable(from: Class[_], to: Class[_]): ValidatedNel[String, Unit] = {
-    val isAssignable = (from, to) match {
+  def isAssignable(from: Class[_], to: Class[_]): Boolean = {
+    (from, to) match {
       case (f, t) if ClassUtils.isAssignable(f, t, true) => true
       // Number double check by hand because lang3 can incorrectly throw false when dealing with java types
       case (f, t) if AllNumbers.contains(f) && AllNumbers.contains(t) =>
         AllNumbers.indexOf(f) >= AllNumbers.indexOf(t)
       case _ => false
     }
-    condNel(isAssignable, (), s"$to is not assignable from $from")
   }
 
 }
-
-object CanBeSubclassDeterminer extends CanBeSubclassDeterminer

components-api/src/main/scala/pl/touk/nussknacker/engine/api/typed/TypeConversionHandler.scala

@@ -87,7 +87,8 @@ object TypeConversionHandler {
         ClassUtils.isAssignable(boxedGivenClass, classOf[Number], true)
 
       case candidate if isDecimalNumber(candidate) =>
-        ConversionFromClassesForDecimals.filter(ClassUtils.isAssignable(boxedGivenClass, _, true)).contains(candidate)
+        import CanBeSubclassDeterminer.isAssignable
+        isAssignable(boxedGivenClass, candidate)
 
       case _ => false
     }