1 files changed, 29 insertions, 18 deletions
diff --git a/core/shared/src/main/scala/magnolia.scala b/core/shared/src/main/scala/magnolia.scala
index c4c13e6..e8350da 100644
--- a/core/shared/src/main/scala/magnolia.scala
+++ b/core/shared/src/main/scala/magnolia.scala
@@ -289,24 +289,35 @@ object Magnolia {
         val preAssignments = caseParams.map(_.typeclass)
 
         val defaults = if (!isValueClass) {
-          val caseClassCompanion = genericType.companion
-
-          // If a companion object is defined with alternative apply methods
-          // it is needed get all the alternatives
-          val constructorMethods =
-            caseClassCompanion.decl(TermName("apply")).alternatives.map(_.asMethod)
-
-          // The last apply method in the alternatives is the one that belongs
-          // to the case class, not the user defined companion object
-          val indexedConstructorParams =
-            constructorMethods.last.paramLists.head.map(_.asTerm).zipWithIndex
-
-          indexedConstructorParams.map {
-            case (p, idx) =>
-              if (p.isParamWithDefault) {
-                val method = TermName("apply$default$" + (idx + 1))
-                q"$scalaPkg.Some(${genericType.typeSymbol.companion.asTerm}.$method)"
-              } else q"$scalaPkg.None"
+
+          val constructorParams = genericType.decls.collect {
+            case a: MethodSymbol if a.isConstructor => a
+          }.head.paramLists.head.map(_.asTerm)
+          val noDefaults = constructorParams.forall(!_.isParamWithDefault)
+
+          if (noDefaults) {
+            constructorParams.map(_ => q"$scalaPkg.None")
+          } else {
+            val caseClassCompanion = genericType.companion
+
+            // If a companion object is defined with alternative apply methods
+            // it is needed get all the alternatives
+            val constructorMethods =
+              caseClassCompanion.decl(TermName("apply")).alternatives.map(_.asMethod)
+
+            // The last apply method in the alternatives is the one that belongs
+            // to the case class, not the user defined companion object
+            val indexedConstructorParams =
+              constructorMethods.last.paramLists.head.map(_.asTerm).zipWithIndex
+          
+            indexedConstructorParams.map {
+              case (p, idx) =>
+                if (p.isParamWithDefault) {
+                  val method = TermName("apply$default$" + (idx + 1))
+                  q"$scalaPkg.Some(${genericType.typeSymbol.companion.asTerm}.$method)"
+                } else q"$scalaPkg.None"
+            }
+
           }
         } else List(q"$scalaPkg.None")