Fix issue 1082

johnynek · Dec 16, 2023 · cf55130 · cf55130
1 parent 48ed6ab
commit cf55130
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Showing 4 changed files with 53 additions and 6 deletions.
diff --git a/core/src/main/scala/org/bykn/bosatsu/KindFormula.scala b/core/src/main/scala/org/bykn/bosatsu/KindFormula.scala
@@ -13,6 +13,7 @@ import org.bykn.bosatsu.rankn.{
   ConstructorFn,
   Ref,
   RefSpace,
+  Type => RankNType,
   TypeEnv,
   DefinedType
 }
@@ -254,13 +255,19 @@ object KindFormula {
       dts: List[DefinedType[Either[KnownShape, Kind.Arg]]]
   ): IorNec[Error, List[DefinedType[Kind.Arg]]] =
     dts
-      .foldM(List.empty[DefinedType[Kind.Arg]]) { (acc, dt) =>
-        solveKind((imports, acc), dt) match {
-          case Validated.Valid(good)   => Ior.Right(good :: acc)
-          case Validated.Invalid(errs) => Ior.Both(errs, acc)
+      .foldM((List.empty[DefinedType[Kind.Arg]], Set.empty[RankNType.TyConst])) { case (st @ (acc, failed), dt) =>
+        if (dt.dependsOn.exists(failed)) {
+          // there was at least one failure already, just return and let that failure signal
+          Ior.Right(st)
+        }
+        else {
+          solveKind((imports, acc), dt) match {
+            case Validated.Valid(good)   => Ior.Right((good :: acc, failed))
+            case Validated.Invalid(errs) => Ior.Both(errs, (acc, failed + dt.toTypeTyConst))
+          }
         }
       }
-      .map(_.reverse)
+      .map(_._1.reverse)
 
   def solveKind[Env: IsTypeEnv](
       imports: Env,

diff --git a/core/src/main/scala/org/bykn/bosatsu/rankn/DefinedType.scala b/core/src/main/scala/org/bykn/bosatsu/rankn/DefinedType.scala
@@ -31,6 +31,13 @@ final case class DefinedType[+A](
   val toTypeTyConst: Type.TyConst =
     Type.TyConst(toTypeConst)
 
+  lazy val dependsOn: List[Type.TyConst] =
+    Type.allConsts(
+      for {
+        cfn <- constructors
+        (_, t) <- cfn.args
+      } yield t
+    )
   /**
    * A type with exactly one constructor is a struct
    */

diff --git a/core/src/main/scala/org/bykn/bosatsu/rankn/Type.scala b/core/src/main/scala/org/bykn/bosatsu/rankn/Type.scala
@@ -168,7 +168,9 @@ object Type {
   case class TyApply(on: Rho, arg: Type) extends Rho {
     lazy val normalize: Rho = TyApply(on.normalize, arg.normalize)
   }
-  case class TyConst(tpe: Const) extends Leaf
+  case class TyConst(tpe: Const) extends Leaf {
+    def isPredef: Boolean = tpe.toDefined.packageName == PackageName.PredefName
+  }
   case class TyVar(toVar: Var) extends Leaf
   case class TyMeta(toMeta: Meta) extends Leaf
 
@@ -382,6 +384,25 @@ object Type {
       case q: Quantified => rootConst(q.in)
     }
 
+  def allConsts(ts: List[Type]): List[TyConst] = {
+    @annotation.tailrec
+    def loop(ts: List[Type], acc: List[TyConst]): List[TyConst] =
+      ts match {
+        case (tyc@TyConst(_)) :: tail => 
+          loop(tail, tyc :: acc)
+        case (TyVar(_) | TyMeta(_)) :: tail =>
+          loop(tail, acc)
+        case TyApply(left, right) :: tail =>
+          loop(left :: right :: tail, acc)
+        case (q: Quantified) :: tail =>
+          loop(q.in :: tail, acc)
+        case Nil =>
+          acc.reverse.distinct
+      }
+
+    loop(ts, Nil)
+  }
+
   object RootConst {
     def unapply(t: Type): Option[Type.TyConst] =
       rootConst(t)

diff --git a/core/src/test/scala/org/bykn/bosatsu/KindFormulaTest.scala b/core/src/test/scala/org/bykn/bosatsu/KindFormulaTest.scala
@@ -278,6 +278,18 @@ struct Bar(foo: Foo)
   test("recursion with type constructors is allowed") {
     allowed("""#
 struct Tree(root: a, children: f[Tree[a, f]])
+""")
+  }
+
+  test("we don't throw when a previous kind fails") {
+    disallowed("""#
+struct Foo[a: -*](get: a)    
+struct Bar[a](foo: Foo[a])
+
+""")
+    disallowed("""#
+struct Bar[a](foo: Foo[a])
+
 """)
   }
 }