diff options
| -rw-r--r-- | src/dotty/tools/dotc/core/Types.scala | 14 | ||||
| -rw-r--r-- | tests/pos/i1652.scala | 5 |
2 files changed, 16 insertions, 3 deletions
diff --git a/src/dotty/tools/dotc/core/Types.scala b/src/dotty/tools/dotc/core/Types.scala index 38913a7d0..b67ff8141 100644 --- a/src/dotty/tools/dotc/core/Types.scala +++ b/src/dotty/tools/dotc/core/Types.scala @@ -2527,6 +2527,8 @@ object Types { case _: MethodType => true case _ => false } + + def isTypeLambda: Boolean = variances.nonEmpty /** PolyParam references to all type parameters of this type */ lazy val paramRefs: List[PolyParam] = paramNames.indices.toList.map(PolyParam(this, _)) @@ -2914,9 +2916,15 @@ object Types { def instantiate(fromBelow: Boolean)(implicit ctx: Context): Type = { val inst = ctx.typeComparer.instanceType(origin, fromBelow) if (ctx.typerState.isGlobalCommittable) - assert(!inst.isInstanceOf[PolyParam], i"bad inst $this := $inst, constr = ${ctx.typerState.constraint}") - // If this fails, you might want to turn on Config.debugCheckConstraintsClosed - // to help find the root of the problem. + inst match { + case inst: PolyParam => + assert(inst.binder.isTypeLambda, i"bad inst $this := $inst, constr = ${ctx.typerState.constraint}") + // If this fails, you might want to turn on Config.debugCheckConstraintsClosed + // to help find the root of the problem. + // Note: Parameters of type lambdas are excluded from the assertion because + // they might arise from ill-kinded code. See #1652 + case _ => + } instantiateWith(inst) } diff --git a/tests/pos/i1652.scala b/tests/pos/i1652.scala new file mode 100644 index 000000000..a48b500fa --- /dev/null +++ b/tests/pos/i1652.scala @@ -0,0 +1,5 @@ +object Test { + val v: Array[Array[Array]] = Array() // happens because of the kindedness error here. + def f[T](w: Array[Array[T]]) = { for (r <- w) () } + f(v) +} |