Put more implementation restrictions on value classes.

Nested objects, classes and lazy vals are disallowed at any
nesting level in value classes; e.g. lazy vals local to a
method defined in a value class. There are still allowed in
universal traits.

This is a temporary, implementation restriction that is planned
to be addressed in future releases of Scala. Error messages has
been updated to communicate that intent.

Moved tests for SI-5582 and SI-6408 to pending folder. They have
to stay there until implementation restrictions are addressed.

Closes SI-6408 and SI-6432.

Review by @odersky, @harrah and @adriaanm.

1 files changed, 4 insertions, 2 deletions

diff --git a/test/files/neg/t6359.check b/test/files/neg/t6359.check
index 2aa1ac5035..5bcdc57331 100644
--- a/test/files/neg/t6359.check
+++ b/test/files/neg/t6359.check
@@ -1,7 +1,9 @@
-t6359.scala:3: error: value class may not have nested module definitions
+t6359.scala:3: error: implementation restriction: nested object is not allowed in value class
+This restriction is planned to be removed in subsequent releases.
       object X
              ^
-t6359.scala:4: error: value class may not have nested class definitions
+t6359.scala:4: error: implementation restriction: nested class is not allowed in value class
+This restriction is planned to be removed in subsequent releases.
       class Y
             ^
 two errors found