test/[n-z]*.go: add documentation
R=golang-dev, bradfitz, r
CC=golang-dev
https://golang.org/cl/5700056
diff --git a/test/typeswitch3.go b/test/typeswitch3.go
index 69a2fca..5475a8a 100644
--- a/test/typeswitch3.go
+++ b/test/typeswitch3.go
@@ -4,6 +4,10 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
+// Verify that erroneous type switches are caught be the compiler.
+// Issue 2700, among other things.
+// Does not compile.
+
package main
import (
