Merge pull request #824 from adriaanm/ticket-4691_6008

[SI-4691, SI-6008] improve patmat analyses: irrefutable user-defined extractors, no-op type tests

2 files changed, 13 insertions, 0 deletions

diff --git a/test/files/pos/t6008.flags b/test/files/pos/t6008.flags
new file mode 100644
index 0000000000..e8fb65d50c
--- /dev/null
+++ b/test/files/pos/t6008.flags
@@ -0,0 +1 @@
+-Xfatal-warnings
\ No newline at end of file
diff --git a/test/files/pos/t6008.scala b/test/files/pos/t6008.scala
new file mode 100644
index 0000000000..84ae19b211
--- /dev/null
+++ b/test/files/pos/t6008.scala
@@ -0,0 +1,12 @@
+// none of these should complain about exhaustivity
+class Test {
+  // It would fail on the following inputs: (_, false), (_, true)
+  def x(in: (Int, Boolean)) = in match { case (i: Int, b: Boolean) => 3 }
+
+  // There is no warning if the Int is ignored or bound without an explicit type:
+  def y(in: (Int, Boolean)) = in match { case (_, b: Boolean) => 3 }
+
+  // Keeping the explicit type for the Int but dropping the one for Boolean presents a spurious warning again:
+  // It would fail on the following input: (_, _)
+  def z(in: (Int, Boolean)) = in match { case (i: Int, b) => 3 }
+}
\ No newline at end of file