SI-7850 CCE in patmat with invalid isEmpty.

Name-based pattern matcher needed some hardening against
unapply methods with the right name but wrong types. Only
isEmpty methods which return Boolean are acceptable.
Catching it directly rather than indirectly also allowed
for better error messages.

1 files changed, 16 insertions, 0 deletions

diff --git a/test/files/neg/t7850.scala b/test/files/neg/t7850.scala
new file mode 100644
index 0000000000..04edad82b5
--- /dev/null
+++ b/test/files/neg/t7850.scala
@@ -0,0 +1,16 @@
+// isEmpty returns non-boolean
+class Casey(a: Int) { def isEmpty = this; def get = this }
+object Casey { def unapply(a: Casey) = a }
+
+// no isEmpty method at all
+class Dingy(a: Int) { def get = this }
+object Dingy { def unapply(a: Dingy) = a }
+
+object Test {
+  def main(args: Array[String]) {
+    val Casey(x1) = new Casey(1)
+    val Dingy(x2) = new Dingy(1)
+    println(s"$x1 $x2")
+  }
+}
+