SI-5932 Tone down non-sensible == warning with refinements.

Errs on the side of avoiding false positives.

2 files changed, 16 insertions, 0 deletions

diff --git a/test/files/pos/t5932.flags b/test/files/pos/t5932.flags
new file mode 100644
index 0000000000..e8fb65d50c
--- /dev/null
+++ b/test/files/pos/t5932.flags
@@ -0,0 +1 @@
+-Xfatal-warnings
\ No newline at end of file
diff --git a/test/files/pos/t5932.scala b/test/files/pos/t5932.scala
new file mode 100644
index 0000000000..d824523d5b
--- /dev/null
+++ b/test/files/pos/t5932.scala
@@ -0,0 +1,15 @@
+class A
+
+case object B extends A
+
+object Test {
+  val x1 = (B: A)
+
+  println(x1 == B) // no warning
+  println(B == x1) // no warning
+
+  val x2 = (B: A with Product)
+
+  println(x2 == B) // no warning
+  println(B == x2) // spurious warning: "always returns false"
+}