Enable test

Author: som-snytt

tests/neg-with-compiler/unused-imports.check

@@ -0,0 +1,23 @@
+-- [E007] Type Mismatch Error: tests/neg-with-compiler/unused-imports.scala:11:15 --------------------------------------
+11 |  def i: Int = "42" // error sanity check
+   |               ^^^^
+   |               Found:    ("42" : String)
+   |               Required: Int
+   |
+   | longer explanation available when compiling with `-explain`
+-- Error: tests/neg-with-compiler/unused-imports.scala:5:16 ------------------------------------------------------------
+5 |import language.postfixOps // error
+  |                ^^^^^^^^^^
+  |                Unused import
+-- Error: tests/neg-with-compiler/unused-imports.scala:6:24 ------------------------------------------------------------
+6 |import scala.concurrent.* // error
+  |                        ^
+  |                        Unused import
+-- Error: tests/neg-with-compiler/unused-imports.scala:12:43 -----------------------------------------------------------
+12 |  import scala.collection.mutable.{HashMap as GoodMap, Seq as _, ListBuffer, Buffer, Set as OK} // error // error
+   |                                   ^^^^^^^^^^^^^^^^^^
+   |                                   Unused import
+-- Error: tests/neg-with-compiler/unused-imports.scala:12:77 -----------------------------------------------------------
+12 |  import scala.collection.mutable.{HashMap as GoodMap, Seq as _, ListBuffer, Buffer, Set as OK} // error // error
+   |                                                                             ^^^^^^
+   |                                                                             Unused import

tests/neg/unused-imports.scala renamed to tests/neg-with-compiler/unused-imports.scala

@@ -1,17 +1,15 @@
-// skalac: -Wunused:imports -Werror -feature
-// disabled because doesn't work under scala3-bootstrapped/test
-// works under testCompilation
+// scalac: -Wunused:imports -Werror -feature
 
 //import language.future
 import language.implicitConversions
-import language.postfixOps //?error
-import scala.concurrent.* //?error
+import language.postfixOps // error
+import scala.concurrent.* // error
 import scala.concurrent.ExecutionContext.Implicits.*
 
 class C:
   def c = 42
   def i: Int = "42" // error sanity check
-  import scala.collection.mutable.{HashMap as GoodMap, Seq as _, ListBuffer, Buffer, Set as OK} //?error //?error
+  import scala.collection.mutable.{HashMap as GoodMap, Seq as _, ListBuffer, Buffer, Set as OK} // error // error
 
   def buf = ListBuffer.empty[String]
   def ok: OK[Int] = ???