From 37b705e87ddb85df05e704bb89dc5aee7c43acb9 Mon Sep 17 00:00:00 2001
From: Saloni Vithalani <skvithalani@yahoo.com>
Date: Sat, 25 Aug 2018 17:22:06 +0530
Subject: [PATCH 1/3] #5008: Add enum example in documentation and a test for
 'case class cannot extend enum'

---
 .../dotc/reporting/ErrorMessagesTests.scala   | 24 +++++++++++++++
 docs/docs/reference/enums/enums.md            | 29 +++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala b/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
index 1af8513e6739..e5e1e5aae3b8 100644
--- a/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
+++ b/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
@@ -19,6 +19,30 @@ class ErrorMessagesTests extends ErrorMessagesTest {
     checkMessagesAfter(FrontEnd.name)("""class Foo""")
     .expectNoErrors
 
+  @Test def caseClassExtendsEnum =
+    checkMessagesAfter(RefChecks.name) {
+      """
+        | enum Foo {}
+        | case class Bar() extends Foo
+      """.stripMargin
+    }
+      .expect { (ictx, messages) ⇒
+        implicit val ctx: Context = ictx
+        assertMessageCount(1, messages)
+        val errorMsg = messages.head
+        assertEquals("normal case class Bar in package <empty> cannot extend an enum", errorMsg.msg)
+      }
+
+  // FIXME
+  @Test def enumExtendsAnothorEnum =
+    checkMessagesAfter(RefChecks.name) {
+      """
+        | enum Foo {}
+        | enum Bar extends Foo {}
+      """.stripMargin
+    }
+      .expectNoErrors
+
   @Test def typeMismatch =
     checkMessagesAfter(FrontEnd.name) {
       """
diff --git a/docs/docs/reference/enums/enums.md b/docs/docs/reference/enums/enums.md
index 3868961e3a1f..17a7bb1aa441 100644
--- a/docs/docs/reference/enums/enums.md
+++ b/docs/docs/reference/enums/enums.md
@@ -88,6 +88,35 @@ object Planet {
       println(s"Your weight on $p is ${p.surfaceWeight(mass)}")
   }
 }
+```
+### A specific use case of enum
+
+Two enums can be combined into a different type as shown below:
+ 
+```scala
+
+trait Animal
+object Animal {
+  def enumValues: Iterable[Animal] = Dog.enumValues ++ Cat.enumValues
+  def enumValueNamed = Dog.enumValueNamed ++ Cat.enumValueNamed
+}
+
+enum Dog extends Animal {
+  case GermanShepherd, Labrador, Boxer
+}
+
+enum Cat extends Animal {
+  case PersianCat, Ragdoll, ScottishFold
+}
+
+object Main {
+  def main(args: Array[String]): Unit = {
+    val values: Iterable[Animal] = Animal.enumValues
+    val boxer_dog: Animal = Animal.enumValueNamed("Boxer")
+    val ragdoll_cat: Animal = Animal.enumValueNamed("Ragdoll")
+  }
+}
+
 ```
 
 ### Implementation

From 97f5dc6076f2411d8ccbb75a887f0c9e5bbafcb6 Mon Sep 17 00:00:00 2001
From: Saloni Vithalani <skvithalani@yahoo.com>
Date: Sat, 25 Aug 2018 18:54:36 +0530
Subject: [PATCH 2/3] Update review changes

---
 .../tools/dotc/reporting/ErrorMessagesTests.scala  | 14 ++------------
 tests/pending/neg/i5008                            |  2 ++
 2 files changed, 4 insertions(+), 12 deletions(-)
 create mode 100644 tests/pending/neg/i5008

diff --git a/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala b/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
index e5e1e5aae3b8..8678a6b2a94b 100644
--- a/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
+++ b/compiler/test/dotty/tools/dotc/reporting/ErrorMessagesTests.scala
@@ -22,8 +22,8 @@ class ErrorMessagesTests extends ErrorMessagesTest {
   @Test def caseClassExtendsEnum =
     checkMessagesAfter(RefChecks.name) {
       """
-        | enum Foo {}
-        | case class Bar() extends Foo
+        |enum Foo {}
+        |case class Bar() extends Foo
       """.stripMargin
     }
       .expect { (ictx, messages) ⇒
@@ -33,16 +33,6 @@ class ErrorMessagesTests extends ErrorMessagesTest {
         assertEquals("normal case class Bar in package <empty> cannot extend an enum", errorMsg.msg)
       }
 
-  // FIXME
-  @Test def enumExtendsAnothorEnum =
-    checkMessagesAfter(RefChecks.name) {
-      """
-        | enum Foo {}
-        | enum Bar extends Foo {}
-      """.stripMargin
-    }
-      .expectNoErrors
-
   @Test def typeMismatch =
     checkMessagesAfter(FrontEnd.name) {
       """
diff --git a/tests/pending/neg/i5008 b/tests/pending/neg/i5008
new file mode 100644
index 000000000000..b543c7bfcb11
--- /dev/null
+++ b/tests/pending/neg/i5008
@@ -0,0 +1,2 @@
+enum Foo {}
+enum Bar extends Foo {} // error
\ No newline at end of file

From 843e52a89f699ce5de4a55345f046cad561c145d Mon Sep 17 00:00:00 2001
From: Saloni Vithalani <skvithalani@yahoo.com>
Date: Sat, 25 Aug 2018 19:06:03 +0530
Subject: [PATCH 3/3] Add newline at the end of file

---
 tests/pending/neg/i5008 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tests/pending/neg/i5008 b/tests/pending/neg/i5008
index b543c7bfcb11..2dc75e6b199c 100644
--- a/tests/pending/neg/i5008
+++ b/tests/pending/neg/i5008
@@ -1,2 +1,2 @@
 enum Foo {}
-enum Bar extends Foo {} // error
\ No newline at end of file
+enum Bar extends Foo {} // error