SI-8040 No warn args to super, main args

`class B(x: X) extends A(x)` uses `x` in ctor,
where it is detectable as an ordinary param.

`implicit class C(val s: String)` may not
use `s` in extension methods, so don't warn.

Don't warn required args to main method.

Don't warn about synthetic isDefinedAt in
anonymous functions, or about defaultCase$.

1 files changed, 4 insertions, 6 deletions

diff --git a/src/repl/scala/tools/nsc/interpreter/IMain.scala b/src/repl/scala/tools/nsc/interpreter/IMain.scala
index a351d2da95..b977ab0939 100644
--- a/src/repl/scala/tools/nsc/interpreter/IMain.scala
+++ b/src/repl/scala/tools/nsc/interpreter/IMain.scala
@@ -751,11 +751,9 @@ class IMain(initialSettings: Settings, protected val out: JPrintWriter) extends
     lazy val evalClass = load(evalPath)
 
     def evalEither = callEither(resultName) match {
-      case Left(ex) => ex match {
-          case ex: NullPointerException => Right(null)
-          case ex => Left(unwrap(ex))
-      }
-      case Right(result) => Right(result)
+      case Right(result)                 => Right(result)
+      case Left(_: NullPointerException) => Right(null)
+      case Left(e)                       => Left(unwrap(e))
     }
 
     def compile(source: String): Boolean = compileAndSaveRun(label, source)
@@ -789,7 +787,7 @@ class IMain(initialSettings: Settings, protected val out: JPrintWriter) extends
           }
           ((pos, msg)) :: loop(filtered)
       }
-      val warnings = loop(run.reporting.allConditionalWarnings.map{case (pos, (msg, since)) => (pos, msg)})
+      val warnings = loop(run.reporting.allConditionalWarnings.map{ case (pos, (msg, since@_)) => (pos, msg) })
       if (warnings.nonEmpty)
         mostRecentWarnings = warnings
     }