From 7b063930f7fc113abb245b11c4954bd78286d77a Mon Sep 17 00:00:00 2001
From: Nicolas Stucki <nicolas.stucki@gmail.com>
Date: Tue, 12 Nov 2019 20:35:04 +0100
Subject: [PATCH] Fix #6475: Print type lambdas in type defs

---
 .../src/dotty/tools/dotc/printing/RefinedPrinter.scala    | 8 ++++----
 tests/pos/i6475.scala                                     | 4 ++++
 2 files changed, 8 insertions(+), 4 deletions(-)
 create mode 100644 tests/pos/i6475.scala

diff --git a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
index 809ea70a236f..85e81d3d586e 100644
--- a/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
+++ b/compiler/src/dotty/tools/dotc/printing/RefinedPrinter.scala
@@ -522,19 +522,19 @@ class RefinedPrinter(_ctx: Context) extends PlainPrinter(_ctx) {
             (varianceText(tree.mods) ~ typeText(nameIdText(tree))) ~
             withEnclosingDef(tree) { tparamsText ~ rhsText }
           }
-        def recur(rhs: Tree, tparamsTxt: => Text): Text = rhs match {
+        def recur(rhs: Tree, tparamsTxt: => Text, printMemberArgs: Boolean): Text = rhs match {
           case impl: Template =>
             templateText(tree, impl)
           case rhs: TypeBoundsTree =>
             typeDefText(tparamsTxt, toText(rhs))
-          case LambdaTypeTree(tparams, body) =>
-            recur(body, tparamsText(tparams))
+          case LambdaTypeTree(tparams, body) if printMemberArgs =>
+            recur(body, tparamsText(tparams), false)
           case rhs: TypeTree if isBounds(rhs.typeOpt) =>
             typeDefText(tparamsTxt, toText(rhs))
           case rhs =>
             typeDefText(tparamsTxt, optText(rhs)(" = " ~ _))
         }
-        recur(rhs, "")
+        recur(rhs, "", true)
       case Import(expr, selectors) =>
         keywordText("import ") ~ importText(expr, selectors)
       case Export(expr, selectors) =>
diff --git a/tests/pos/i6475.scala b/tests/pos/i6475.scala
new file mode 100644
index 000000000000..f0ebdf5de493
--- /dev/null
+++ b/tests/pos/i6475.scala
@@ -0,0 +1,4 @@
+object Foo1 { type T[+A] = (A, Int) }
+object Foo2 { type T[+A] = [+B] =>> (A, B) }
+object Foo3 { type T[+A] = [+B] =>> [C] =>> (A, B) }
+object Foo4 { type T = [+A] =>> [+B] =>> [C] =>> (A, B) }