Fix #836 - Scala3 macro nesting class

play-json/shared/src/main/scala-3/play/api/libs/json/JsMacroImpl.scala

@@ -319,7 +319,6 @@ object JsMacroImpl { // TODO: debug
       val types   = tprElements.map(_._2)
       val resolve = resolver[Reads, T](forwardExpr, debug)(readsTpe)
       val compCls = tpr.typeSymbol.companionClass
-      val compMod = Ref(tpr.typeSymbol.companionModule)
 
       val (optional, required) = tprElements.zipWithIndex
         .map { case ((sym, rpt), i) =>
@@ -330,7 +329,7 @@ object JsMacroImpl { // TODO: debug
               val default: Option[Expr[t]] =
                 compCls.declaredMethod(f"$$lessinit$$greater$$default$$" + (i + 1)).headOption.collect {
                   case defaultSym if sym.flags.is(Flags.HasDefault) =>
-                    compMod.select(defaultSym).asExprOf[t]
+                    Ref(tpr.typeSymbol.companionModule).select(defaultSym).asExprOf[t]
                 }
 
               ReadableField(sym, i, pt, default)

play-json/shared/src/test/scala/play/api/libs/json/MacroSpec.scala

@@ -505,6 +505,19 @@ class MacroSpec extends AnyWordSpec with Matchers with org.scalatestplus.scalach
 
       reader.reads(jsPref2).mustEqual(JsSuccess(pref2))
     }
+
+    "handle nesting class" in {
+      implicit val textIdFormat: Format[TextId] = Json.valueFormat[TextId]
+
+      val nesting = new NestingClass
+
+      val expected     = nesting.Test(Some(new TextId("foo")))
+      val expectedJson = Json.obj("underlying" -> "foo")
+
+      Json.toJson(expected).mustEqual(expectedJson)
+
+      nesting.Test.format.reads(expectedJson).mustEqual(JsSuccess(expected))
+    }
   }
 }
 
@@ -602,4 +615,13 @@ object MacroSpec {
   }
 
   case class Preference[V](key: String, kind: PrefKind.Aux[V], value: V)
+
+  class NestingClass {
+    case class Test(underlying: Option[TextId])
+
+    object Test {
+      implicit def format(implicit textIdFormat: Format[TextId]): Format[Test] =
+        Json.format[Test]
+    }
+  }
 }