Merge pull request #3597 from som-snytt/issue/5905-feature-help

SI-5905 Sanity check -language options

1 files changed, 31 insertions, 0 deletions

diff --git a/test/files/run/t5905-features.scala b/test/files/run/t5905-features.scala
new file mode 100644
index 0000000000..547a521cb5
--- /dev/null
+++ b/test/files/run/t5905-features.scala
@@ -0,0 +1,31 @@
+
+import tools.partest.DirectTest
+
+// verify that all languageFeature names are accepted by -language
+object Test extends DirectTest {
+  override def code = "class Code { def f = (1 to 10) size }" // exercise a feature to sanity-check coverage of -language options
+
+  override def extraSettings = s"-usejavacp -d ${testOutput.path}"
+
+  override def show() = {
+    val global = newCompiler("-Ystop-after:typer")
+    compileString(global)("")   // warm me up, scotty
+    import global._
+    exitingTyper {
+      //def isFeature(s: Symbol) = s.annotations.exists((a: AnnotationInfo) => a.tpe <:< typeOf[scala.annotation.meta.languageFeature])
+      def isFeature(s: Symbol) = s hasAnnotation definitions.LanguageFeatureAnnot
+      val langf  = definitions.languageFeatureModule.typeSignature
+      val feats  = langf.declarations filter (s => isFeature(s)) map (_.name.decoded)
+      val xmen   = langf.member(TermName("experimental")).typeSignature.declarations filter (s => isFeature(s)) map (s => s"experimental.${s.name.decoded}")
+      val all    = (feats ++ xmen) mkString ","
+
+      assert(feats.nonEmpty, "Test must find feature flags.")
+
+      //compile("junk")   // tragically, does not fail the test
+
+      //dynamics,postfixOps,reflectiveCalls,implicitConversions,higherKinds,existentials,experimental.macros
+      compile(s"-language:$all")
+    }
+  }
+}
+