Made -Xfatal-warnings less immediately fatal.

Instead of changing warnings to errors mid-stream, at the end of
a run I check for condition "no errors, some warnings, and fatal
warnings" and then generate an error at that point.  This is
necessary to test for some warnings which come from later stages.

1 files changed, 10 insertions, 8 deletions

diff --git a/test/files/neg/t4851.check b/test/files/neg/t4851.check
index 8011350f23..0fd66b9efe 100644
--- a/test/files/neg/t4851.check
+++ b/test/files/neg/t4851.check
@@ -1,43 +1,45 @@
-S.scala:2: error: Adapting argument list by inserting (): leaky (Object-receiving) target makes this especially dangerous.
+S.scala:2: warning: Adapting argument list by inserting (): leaky (Object-receiving) target makes this especially dangerous.
         signature: J(x: Any): J
   given arguments: <none>
  after adaptation: new J((): Unit)
   val x1 = new J
            ^
-S.scala:3: error: Adapting argument list by inserting (): leaky (Object-receiving) target makes this especially dangerous.
+S.scala:3: warning: Adapting argument list by inserting (): leaky (Object-receiving) target makes this especially dangerous.
         signature: J(x: Any): J
   given arguments: <none>
  after adaptation: new J((): Unit)
   val x2 = new J()
            ^
-S.scala:4: error: Adapting argument list by creating a 5-tuple: this may not be what you want.
+S.scala:4: warning: Adapting argument list by creating a 5-tuple: this may not be what you want.
         signature: J(x: Any): J
   given arguments: 1, 2, 3, 4, 5
  after adaptation: new J((1, 2, 3, 4, 5): (Int, Int, Int, Int, Int))
   val x3 = new J(1, 2, 3, 4, 5)
            ^
-S.scala:6: error: Adapting argument list by creating a 3-tuple: this may not be what you want.
+S.scala:6: warning: Adapting argument list by creating a 3-tuple: this may not be what you want.
         signature: Some.apply[A](x: A): Some[A]
   given arguments: 1, 2, 3
  after adaptation: Some((1, 2, 3): (Int, Int, Int))
   val y1 = Some(1, 2, 3)
                ^
-S.scala:7: error: Adapting argument list by creating a 3-tuple: this may not be what you want.
+S.scala:7: warning: Adapting argument list by creating a 3-tuple: this may not be what you want.
         signature: Some(x: A): Some[A]
   given arguments: 1, 2, 3
  after adaptation: new Some((1, 2, 3): (Int, Int, Int))
   val y2 = new Some(1, 2, 3)
            ^
-S.scala:9: error: Adapting argument list by inserting (): this is unlikely to be what you want.
+S.scala:9: warning: Adapting argument list by inserting (): this is unlikely to be what you want.
         signature: J2[T](x: T): J2[T]
   given arguments: <none>
  after adaptation: new J2((): Unit)
   val z1 = new J2
            ^
-S.scala:10: error: Adapting argument list by inserting (): this is unlikely to be what you want.
+S.scala:10: warning: Adapting argument list by inserting (): this is unlikely to be what you want.
         signature: J2[T](x: T): J2[T]
   given arguments: <none>
  after adaptation: new J2((): Unit)
   val z2 = new J2()
            ^
-7 errors found
+error: No warnings can be incurred under -Xfatal-warnings.
+7 warnings found
+one error found