Add better error message on StackOverflow in macros, prevent SO in so…

…me cases with Scala 3 enums mapping
scalalandio · May 7, 2024 · a34c153 · a34c153
1 parent 4a37a24
commit a34c153
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Showing 4 changed files with 15 additions and 6 deletions.
diff --git a/...in/scala-3/io/scalaland/chimney/internal/compiletime/datatypes/ProductTypesPlatform.scala b/...in/scala-3/io/scalaland/chimney/internal/compiletime/datatypes/ProductTypesPlatform.scala
@@ -63,7 +63,8 @@ trait ProductTypesPlatform extends ProductTypes { this: DefinitionsPlatform =>
     }
     def isCaseVal[A](implicit A: Type[A]): Boolean = {
       val sym = TypeRepr.of(using A).typeSymbol
-      sym.isPublic && sym.flags.is(Flags.Case | Flags.Enum | Flags.JavaStatic)
+      sym.isPublic && sym.flags
+        .is(Flags.Case | Flags.Enum) && (sym.flags.is(Flags.JavaStatic) || sym.flags.is(Flags.StableRealizable))
     }
     def isJavaEnumValue[A: Type]: Boolean =
       Type[A] <:< scala.quoted.Type.of[java.lang.Enum[?]] && !TypeRepr.of[A].typeSymbol.isAbstract

diff --git a/...ala-3/io/scalaland/chimney/internal/compiletime/datatypes/SealedHierarchiesPlatform.scala b/...ala-3/io/scalaland/chimney/internal/compiletime/datatypes/SealedHierarchiesPlatform.scala
@@ -14,7 +14,7 @@ trait SealedHierarchiesPlatform extends SealedHierarchies { this: DefinitionsPla
 
     def isSealed[A: Type]: Boolean = {
       val flags = TypeRepr.of[A].typeSymbol.flags
-      flags.is(Flags.Enum) || flags.is(Flags.Sealed)
+      flags.is(Flags.Sealed) // do NOT use flags.is(Flags.Enum) since it will also match enums cases!
     }
 
     def parse[A: Type]: Option[Enum[A]] =

diff --git a/chimney/src/main/scala/io/scalaland/chimney/internal/compiletime/DerivationError.scala b/chimney/src/main/scala/io/scalaland/chimney/internal/compiletime/DerivationError.scala
@@ -14,8 +14,16 @@ object DerivationError {
       .collectFirst {
         case MacroException(exception) =>
           val stackTrace =
-            exception.getStackTrace.view.take(10).map(ste => s"  \t${Console.RED}$ste${Console.RESET}").mkString("\n")
-          s"  macro expansion thrown exception!: $exception:\n$stackTrace\n  \t${Console.RED}...${Console.RESET}"
+            exception.getStackTrace.view
+              .take(10)
+              .map(ste => s"  \t${Console.RED}$ste${Console.RESET}")
+              .mkString("\n") + s"\n  \t${Console.RED}...${Console.RESET}"
+          exception match {
+            case _: StackOverflowError =>
+              s"  macro expansion thrown StackOverflow - usually it's a sign that JVM need larger Stack. Increase it with e.g. -Xss64m passed to JVM!: $exception:\n$stackTrace"
+            case _ =>
+              s"  macro expansion thrown exception!: $exception:\n$stackTrace"
+          }
         case NotYetImplemented(what) =>
           s"  derivation failed because functionality $what is not yet implemented!"
       }

diff --git a/docs/docs/troubleshooting.md b/docs/docs/troubleshooting.md
@@ -1677,8 +1677,8 @@ On Scala 2 `java.lang.UnsupportedOperationException: Position.point on NoPositio
 recursive derivation (not only in Chimney) can overflow this stack trace, but on Scala 2 it can become notorious in
 the form of an empty value used by the macro to report where error happened.
 
-These issues can be addressed by increasing the compiler's JVM stack size, passing it e.g. -Xss64m (to increase the size
-to 64MB).
+These issues can be addressed by increasing the compiler's JVM stack size, passing it e.g. `-Xss64m` (to increase
+the size to 64MB).
 
 However, if you are using the compiler's flags to report unused definitions when macros are involved, there can also be
 an error caused by [scala/bug#12895](https://github.com/scala/bug/issues/12895). This bug was fixed in Scala 2.13.14,