From cec3285154bc030152a7efa69ef724b0c7c90615 Mon Sep 17 00:00:00 2001
From: Nabil Abdel-Hafeez <7283535+987Nabil@users.noreply.github.com>
Date: Fri, 30 Jun 2023 01:54:08 +0200
Subject: [PATCH] Fix: generic fields default for Scala 3, find default value
 for Scala 2

---
 .../scala-2/zio/schema/DeriveSchema.scala     |  3 +-
 .../scala-3/zio/schema/DeriveSchema.scala     |  8 ++++--
 .../test/scala/zio/schema/DeriveSpec.scala    | 28 +++++++++++++++++--
 3 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/zio-schema-derivation/shared/src/main/scala-2/zio/schema/DeriveSchema.scala b/zio-schema-derivation/shared/src/main/scala-2/zio/schema/DeriveSchema.scala
index ca36d8a63..94709ff49 100644
--- a/zio-schema-derivation/shared/src/main/scala-2/zio/schema/DeriveSchema.scala
+++ b/zio-schema-derivation/shared/src/main/scala-2/zio/schema/DeriveSchema.scala
@@ -233,8 +233,7 @@ object DeriveSchema {
                   val defaultApply = tpe.companion.member(TermName(s"apply$$default$$${i + 1}"))
                   Some(i -> defaultInit)
                     .filter(_ => defaultInit != NoSymbol)
-                    .orElse(Some(i -> defaultApply))
-                    .filter(_ => defaultApply != NoSymbol)
+                    .orElse(Some(i -> defaultApply).filter(_ => defaultApply != NoSymbol))
                 } else None
             }
             .toMap
diff --git a/zio-schema-derivation/shared/src/main/scala-3/zio/schema/DeriveSchema.scala b/zio-schema-derivation/shared/src/main/scala-3/zio/schema/DeriveSchema.scala
index 0596a1540..8162b1aa0 100644
--- a/zio-schema-derivation/shared/src/main/scala-3/zio/schema/DeriveSchema.scala
+++ b/zio-schema-derivation/shared/src/main/scala-3/zio/schema/DeriveSchema.scala
@@ -288,8 +288,12 @@ private case class DeriveSchema()(using val ctx: Quotes) extends ReflectionUtils
                 .declaredMethod(s"$$apply$$default$$$i")
                 .headOption
             )
-            .map(Select(Ref(from.companionModule), _).asExpr)
-      ).zip(from.primaryConstructor.paramSymss.flatten.map(_.name)).collect{case (Some(expr), name) => name -> expr}.toMap
+            .map { s =>
+              val select = Select(Ref(from.companionModule), s)
+              if (select.isExpr) select.asExpr
+              else select.appliedToType(TypeRepr.of[Any]).asExpr
+            }
+      ).zip(from.primaryConstructor.paramSymss.flatten.filter(!_.isTypeParam).map(_.name)).collect{ case (Some(expr), name) => name -> expr }.toMap
 
   private def fromConstructor(from: Symbol): scala.collection.Map[String, List[Expr[Any]]] = {
       val defaults = defaultValues(from)
diff --git a/zio-schema-derivation/shared/src/test/scala/zio/schema/DeriveSpec.scala b/zio-schema-derivation/shared/src/test/scala/zio/schema/DeriveSpec.scala
index da157f402..a5bf6a2c8 100644
--- a/zio-schema-derivation/shared/src/test/scala/zio/schema/DeriveSpec.scala
+++ b/zio-schema-derivation/shared/src/test/scala/zio/schema/DeriveSpec.scala
@@ -2,12 +2,12 @@ package zio.schema
 
 import scala.annotation.nowarn
 import scala.reflect.ClassTag
-
 import zio.schema.Deriver.WrappedF
 import zio.schema.Schema.Field
+import zio.schema.StandardType.IntType
 import zio.schema.annotation.fieldDefaultValue
-import zio.test.{ Spec, TestEnvironment, ZIOSpecDefault, assertTrue }
-import zio.{ Chunk, Scope }
+import zio.test.{Spec, TestEnvironment, ZIOSpecDefault, assertTrue}
+import zio.{Chunk, Scope}
 
 object DeriveSpec extends ZIOSpecDefault with VersionSpecificDeriveSpec {
   override def spec: Spec[TestEnvironment with Scope, Any] =
@@ -174,6 +174,19 @@ object DeriveSpec extends ZIOSpecDefault with VersionSpecificDeriveSpec {
               .exists(a => a.isInstanceOf[fieldDefaultValue[_]] && a.asInstanceOf[fieldDefaultValue[Int]].value == 42)
           )
         },
+        test("use case class default values of generic class") {
+          val capturedSchema = Derive.derive[CapturedSchema, GenericRecordWithDefaultValue[Int]](schemaCapturer)
+          val annotations = capturedSchema.schema
+            .asInstanceOf[Schema.Record[GenericRecordWithDefaultValue[Int]]]
+            .fields(0)
+            .annotations
+          assertTrue {
+            annotations.exists { a =>
+              a.isInstanceOf[fieldDefaultValue[_]] &&
+                a.asInstanceOf[fieldDefaultValue[Option[Int]]].value == None
+            }
+          }
+        },
         test("prefer field annotations over case class default values") {
           val capturedSchema = Derive.derive[CapturedSchema, RecordWithDefaultValue](schemaCapturer)
           val annotations = capturedSchema.schema
@@ -304,6 +317,15 @@ object DeriveSpec extends ZIOSpecDefault with VersionSpecificDeriveSpec {
     implicit val schema: Schema[RecordWithDefaultValue] = DeriveSchema.gen[RecordWithDefaultValue]
   }
 
+  case class GenericRecordWithDefaultValue[T](int: Option[T] = None, @fieldDefaultValue(52) int2: Int = 42)
+
+  object GenericRecordWithDefaultValue {
+    //explicitly Int, because generic implicit definition leads to "Schema derivation exceeded" error
+    implicit def schema: Schema[GenericRecordWithDefaultValue[Int]] = {
+      DeriveSchema.gen[GenericRecordWithDefaultValue[Int]]
+    }
+  }
+
   sealed trait Enum1
 
   object Enum1 {