Scala 3 Case Object fix (#376)

Fixes #375
com-lihaoyi · Dec 26, 2021 · 9655b81 · 9655b81
1 parent dd814df
commit 9655b81
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Showing 2 changed files with 30 additions and 6 deletions.
diff --git a/implicits/src-3/upickle/implicits/macros.scala b/implicits/src-3/upickle/implicits/macros.scala
@@ -3,13 +3,16 @@ package upickle.implicits.macros
 import scala.quoted.{ given, _ }
 import deriving._, compiletime._
 
-inline def getDefaultParams[T]: Map[String, AnyRef] = ${ getDefaultParmasImpl[T] }
-def getDefaultParmasImpl[T](using Quotes, Type[T]): Expr[Map[String, AnyRef]] =
+inline def getDefaultParams[T]: Map[String, AnyRef] = ${ getDefaultParamsImpl[T] }
+def getDefaultParamsImpl[T](using Quotes, Type[T]): Expr[Map[String, AnyRef]] =
   import quotes.reflect._
   val sym = TypeTree.of[T].symbol
 
   if (sym.isClassDef) {
-    val comp = if (sym.isClassDef) sym.companionClass else sym
+    val comp =
+      if (sym.isClassDef && !sym.companionClass.isNoSymbol ) sym.companionClass
+      else sym
+
     val hasDefaults =
       for p <- sym.caseFields
       yield p.flags.is(Flags.HasDefault)
@@ -29,7 +32,7 @@ def getDefaultParmasImpl[T](using Quotes, Type[T]): Expr[Map[String, AnyRef]] =
   } else {
     '{ Map.empty }
   }
-end getDefaultParmasImpl
+end getDefaultParamsImpl
 
 inline def summonList[T <: Tuple]: List[_] =
   inline erasedValue[T] match

diff --git a/upickle/test/src-3/upickle/Derivation.scala b/upickle/test/src-3/upickle/Derivation.scala
@@ -18,6 +18,10 @@ case class Cat(name: String, owner: Person)
 case class Dog(name: String, age: Int)
   derives ReadWriter
 
+case object Cthulu
+  extends Animal
+  derives ReadWriter
+
 object DerivationTests extends TestSuite {
 
   val tests = Tests {
@@ -63,7 +67,24 @@ object DerivationTests extends TestSuite {
       val dog = Dog("Ball", 10)
       val result = write(dog)
       val expected = """{"name":"Ball","age":10}"""
-      println(result == expected)
+      assert(result == expected)
+    }
+
+    test("caseObjectWriter") - {
+      val result1 = write(Cthulu)
+
+      val animal: Animal = Cthulu
+      val result2 = write(animal)
+
+      val expected = """{"$type":"upickle.Cthulu"}"""
+      assert(result1 == expected)
+      assert(result2 == expected)
+    }
+
+    test ("caseObjectReader") - {
+      val json = """{"$type":"upickle.Cthulu"}"""
+      val result = read[Animal](json)
+      assert(result == Cthulu)
     }
 
     test("traitWriter") - {
@@ -73,7 +94,7 @@ object DerivationTests extends TestSuite {
       assert(result == expected)
     }
 
-    test("readWritrer") - {
+    test("readWriter") - {
       val rw = summon[ReadWriter[Animal]]
       val person = Person("Peter", "Somewhere", 30)
       val json = write(person)(rw)