From e3b49320e7343def793ffe50cb4384e1c34eef70 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Tue, 2 Jan 2018 13:35:49 +0100
Subject: [PATCH] Fix #3433: Fix determining typeParams for structural type
 members

---
 compiler/src/dotty/tools/dotc/core/TypeApplications.scala | 1 +
 tests/pos/i3433.scala                                     | 4 ++++
 2 files changed, 5 insertions(+)
 create mode 100644 tests/pos/i3433.scala

diff --git a/compiler/src/dotty/tools/dotc/core/TypeApplications.scala b/compiler/src/dotty/tools/dotc/core/TypeApplications.scala
index b1c1aeb4db3e..5fef29032fd7 100644
--- a/compiler/src/dotty/tools/dotc/core/TypeApplications.scala
+++ b/compiler/src/dotty/tools/dotc/core/TypeApplications.scala
@@ -172,6 +172,7 @@ class TypeApplications(val self: Type) extends AnyVal {
       case self: TypeRef =>
         val tsym = self.symbol
         if (tsym.isClass) tsym.typeParams
+        else if (!tsym.exists) self.info.typeParams
         else if (!tsym.isCompleting) tsym.info.typeParams
         else Nil
       case self: AppliedType =>
diff --git a/tests/pos/i3433.scala b/tests/pos/i3433.scala
new file mode 100644
index 000000000000..7c6dbd25bc42
--- /dev/null
+++ b/tests/pos/i3433.scala
@@ -0,0 +1,4 @@
+object Test {
+  type Const[t] = { type L[x] = t }
+  type Bar[a] = Const[Int]#L[a]
+}