SI-8040 Xlint enables unused warnings

`-Ywarn-unused-import` is deprecated in favor of `-Ywarn-unused:imports`.

`-Xlint` does not yet enable `-Ywarn-unused:patvars`.

But the default for `-Ywarn-unused` is everything, including `patvars`.

So `-Xlint:unused` is the populist option, `-Ywarn-unused` more exclusive.

Tests are fixed by narrowing scope of `-Xlint` when specified.

1 files changed, 6 insertions, 0 deletions

diff --git a/test/files/pos/t8040.scala b/test/files/pos/t8040.scala
new file mode 100644
index 0000000000..b067f36b0b
--- /dev/null
+++ b/test/files/pos/t8040.scala
@@ -0,0 +1,6 @@
+
+object Test {
+  implicit class C(val sc: StringContext) {                 // no warn unused sc
+    def c(args: Any*): String = "c?" + args.mkString(",")   // would warn unused args
+  }
+}