Add a way to tests only a small subset of files

Author: nicolasstucki

dotty-scala-library-from-tasty-tests/test/LibraryTest.scala

@@ -23,6 +23,13 @@ class TastyInspectorTest:
   @Test def testFromTasty: Unit =
     compileFromTasty(loadBlacklisted.union(compileBlacklisted))
 
+  @Ignore
+  @Test def testWhiteListFromTasty: Unit =
+    val whitelist = Set(
+      "scala.collection.mutable.StringBuilder"
+    )
+    compileFromTasty(x => !whitelist(x))
+
   @Test def blacklistNoDuplicates =
     def testDup(name: String, list: List[String], set: Set[String]) =
       assert(list.size == set.size,