From 46f4f938e6e839a83e8218918b79001113adf885 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Wed, 13 Jan 2021 11:45:33 +0100
Subject: [PATCH 1/3] Tighten condition when to check enum constructors

Fixes #11081
---
 compiler/src/dotty/tools/dotc/typer/Checking.scala | 2 +-
 tests/pos/i11081.scala                             | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)
 create mode 100644 tests/pos/i11081.scala

diff --git a/compiler/src/dotty/tools/dotc/typer/Checking.scala b/compiler/src/dotty/tools/dotc/typer/Checking.scala
index e2f160142e6d..dc39a21cb141 100644
--- a/compiler/src/dotty/tools/dotc/typer/Checking.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Checking.scala
@@ -1193,7 +1193,7 @@ trait Checking {
         checkRefsLegal(tree, cdef.symbol, allowAccess, "enum case")
       }
 
-      if (stat.symbol.is(Case))
+      if (stat.symbol.isAllOf(EnumCase))
         stat match {
           case TypeDef(_, Template(DefDef(_, paramss, _, _), parents, _, _)) =>
             paramss.foreach(_.foreach(check))
diff --git a/tests/pos/i11081.scala b/tests/pos/i11081.scala
new file mode 100644
index 000000000000..60bd5d5fe16b
--- /dev/null
+++ b/tests/pos/i11081.scala
@@ -0,0 +1,5 @@
+enum Outer:
+  case Foo
+object Outer:
+  trait Bar
+  case class Baz(bar: Bar)
\ No newline at end of file

From 788ae4ee8a75c81d8436f8b571406736883b88d7 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Wed, 13 Jan 2021 15:56:18 +0100
Subject: [PATCH 2/3] Also strengthen checking condition for default arguments

---
 compiler/src/dotty/tools/dotc/typer/Checking.scala | 2 +-
 tests/pos/i11081.scala                             | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/compiler/src/dotty/tools/dotc/typer/Checking.scala b/compiler/src/dotty/tools/dotc/typer/Checking.scala
index dc39a21cb141..efad815cb2d1 100644
--- a/compiler/src/dotty/tools/dotc/typer/Checking.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Checking.scala
@@ -1207,7 +1207,7 @@ trait Checking {
             }
           case _ =>
         }
-      else if (stat.symbol.is(Module) && stat.symbol.linkedClass.is(Case))
+      else if (stat.symbol.is(Module) && stat.symbol.linkedClass.isAllOf(EnumCase))
         stat match {
           case TypeDef(_, impl: Template) =>
             for ((defaultGetter @
diff --git a/tests/pos/i11081.scala b/tests/pos/i11081.scala
index 60bd5d5fe16b..cd333d7e407d 100644
--- a/tests/pos/i11081.scala
+++ b/tests/pos/i11081.scala
@@ -2,4 +2,5 @@ enum Outer:
   case Foo
 object Outer:
   trait Bar
-  case class Baz(bar: Bar)
\ No newline at end of file
+  case class Baz(bar: Bar)
+  case class Bam(bar: Bar = new Bar() {})

From 79ee0a2a7ac809a55ea7f6e64cf4a9866597c9f8 Mon Sep 17 00:00:00 2001
From: Martin Odersky <odersky@gmail.com>
Date: Wed, 13 Jan 2021 18:43:39 +0100
Subject: [PATCH 3/3] Address review comment

---
 compiler/src/dotty/tools/dotc/typer/Checking.scala | 10 +++++-----
 tests/neg/i11081.scala                             |  6 ++++++
 2 files changed, 11 insertions(+), 5 deletions(-)
 create mode 100644 tests/neg/i11081.scala

diff --git a/compiler/src/dotty/tools/dotc/typer/Checking.scala b/compiler/src/dotty/tools/dotc/typer/Checking.scala
index efad815cb2d1..a7a509f0f804 100644
--- a/compiler/src/dotty/tools/dotc/typer/Checking.scala
+++ b/compiler/src/dotty/tools/dotc/typer/Checking.scala
@@ -1180,7 +1180,7 @@ trait Checking {
    */
   def checkEnumCaseRefsLegal(cdef: TypeDef, enumCtx: Context)(using Context): Unit = {
 
-    def checkCaseOrDefault(stat: Tree, caseCtx: Context) = {
+    def checkEnumCaseOrDefault(stat: Tree, caseCtx: Context) = {
 
       def check(tree: Tree) = {
         // allow access to `sym` if a typedIdent just outside the enclosing enum
@@ -1219,16 +1219,16 @@ trait Checking {
 
     cdef.rhs match {
       case impl: Template =>
-        def isCase(stat: Tree) = stat match {
-          case _: ValDef | _: TypeDef => stat.symbol.is(Case)
+        def isEnumCase(stat: Tree) = stat match {
+          case _: ValDef | _: TypeDef => stat.symbol.isAllOf(EnumCase)
           case _ => false
         }
         val cases =
-          for (stat <- impl.body if isCase(stat))
+          for (stat <- impl.body if isEnumCase(stat))
           yield untpd.ImportSelector(untpd.Ident(stat.symbol.name.toTermName))
         val caseImport: Import = Import(ref(cdef.symbol), cases)
         val caseCtx = enumCtx.importContext(caseImport, caseImport.symbol)
-        for (stat <- impl.body) checkCaseOrDefault(stat, caseCtx)
+        for (stat <- impl.body) checkEnumCaseOrDefault(stat, caseCtx)
       case _ =>
     }
   }
diff --git a/tests/neg/i11081.scala b/tests/neg/i11081.scala
new file mode 100644
index 000000000000..7c1e6ce6dec6
--- /dev/null
+++ b/tests/neg/i11081.scala
@@ -0,0 +1,6 @@
+enum Outer:
+  case Foo(u: Unavailable) // error
+  case Bar(u: DefinitelyNotAvailable) // error
+object Outer:
+  class Unavailable(i: Int)
+  case class DefinitelyNotAvailable()