Merge pull request #1946 from retronym/ticket/6231

SI-6231 Report unsupported free var capture by a trait.

2 files changed, 21 insertions, 0 deletions

diff --git a/test/files/neg/t6231.check b/test/files/neg/t6231.check
new file mode 100644
index 0000000000..b27961d393
--- /dev/null
+++ b/test/files/neg/t6231.check
@@ -0,0 +1,6 @@
+t6231.scala:4: error: Implementation restriction: local trait Bug$X$1 is unable to automatically capture the
+free variable value ev$1 on behalf of anonymous class anonfun$qux$1. You can manually assign it to a val inside the trait,
+and refer that that val in anonymous class anonfun$qux$1. For more details, see SI-6231.
+      def qux = { () => ev }
+                        ^
+one error found
diff --git a/test/files/neg/t6231.scala b/test/files/neg/t6231.scala
new file mode 100644
index 0000000000..1e5b4e0e1a
--- /dev/null
+++ b/test/files/neg/t6231.scala
@@ -0,0 +1,15 @@
+object Bug {
+  def bar(ev: Any) = {
+    trait X {
+      def qux = { () => ev }
+    }
+    new X {}.qux()
+
+    // workaround
+    trait Y {
+      val ev2 = ev // manually capture `ev` so that `ev2` is added to the trait interface.
+      def qux = { () => ev2 }
+    }
+  }
+}
+