eagerly initializes lazy vals and objects in runtime reflection

The code to do so is curated with the help of a generator. Because this
needs to inspect code post-typer, the code generator is run during partest
as a code-validator. We could concievably do the same with a macro, but
this approach might be a better starting point which macros continue to
stabilize.

Removes Definitions.AnyRefModule and an already deprecated alias, as
these have been throwing exceptions for more than a year since 6bb5975289.
They used to be used by AnyRef specialization.

1 files changed, 82 insertions, 0 deletions

diff --git a/test/files/run/t6240-universe-code-gen.scala b/test/files/run/t6240-universe-code-gen.scala
new file mode 100644
index 0000000000..84691639bd
--- /dev/null
+++ b/test/files/run/t6240-universe-code-gen.scala
@@ -0,0 +1,82 @@
+import scala.tools.partest.nest.FileManager._
+
+object Test extends App {
+  val cm = reflect.runtime.currentMirror
+  val u = cm.universe
+  import u._
+
+  val JavaUniverseTpe = typeOf[reflect.runtime.JavaUniverse]
+  val DefinitionsModule = JavaUniverseTpe.member(TermName("definitions"))
+
+  def forceCode(prefix: String, tp: Type): String = {
+    def isLazyAccessorOrObject(sym: Symbol) = (
+          (sym.isMethod && sym.asMethod.isLazy)
+       || sym.isModule
+    )
+    val forcables = tp.members.sorted.filter(isLazyAccessorOrObject)
+    forcables.map {
+      sym =>
+        val path = s"$prefix.${sym.name}"
+        "    " + (
+          if (sym.isPrivate || sym.isProtected) s"// inaccessible: $path"
+          else path
+        )
+    }.mkString("\n")
+  }
+
+  val code =
+    s"""|// Generated Code, validated by run/t6240-universe-code-gen.scala
+        |package scala.reflect
+        |package runtime
+        |
+        |trait JavaUniverseForce { self: runtime.JavaUniverse  =>
+        |  def force() {
+        |    Literal(Constant(42)).duplicate
+        |    nme.flattenedName()
+        |    nme.raw
+        |    WeakTypeTag
+        |    TypeTag
+        |    TypeTag.Byte.tpe
+        |    TypeTag.Short.tpe
+        |    TypeTag.Char.tpe
+        |    TypeTag.Int.tpe
+        |    TypeTag.Long.tpe
+        |    TypeTag.Float.tpe
+        |    TypeTag.Double.tpe
+        |    TypeTag.Boolean.tpe
+        |    TypeTag.Unit.tpe
+        |    TypeTag.Any.tpe
+        |    TypeTag.AnyVal.tpe
+        |    TypeTag.AnyRef.tpe
+        |    TypeTag.Object.tpe
+        |    TypeTag.Nothing.tpe
+        |    TypeTag.Null.tpe
+        |
+        |${forceCode("this", JavaUniverseTpe)}
+        |${forceCode("definitions", DefinitionsModule.typeSignature)}
+        |${forceCode("refChecks", typeOf[scala.reflect.internal.transform.RefChecks])}
+        |${forceCode("uncurry", typeOf[scala.reflect.internal.transform.UnCurry])}
+        |${forceCode("erasure", typeOf[scala.reflect.internal.transform.Erasure])}
+        |  }
+        |}""".stripMargin
+
+  import java.io.File
+  val testFile = new File(sys.props("partest.test-path"))
+  val actualFile = new java.io.File(testFile.getParent + "/../../../src/reflect/scala/reflect/runtime/JavaUniverseForce.scala").getCanonicalFile
+  val actual = scala.io.Source.fromFile(actualFile)
+  val actualLines = actual.getLines.toList
+  val generatedLines = code.lines.toList
+  if (actualLines != generatedLines) {
+    val msg = s"""|${actualFile} must be updated.
+                  |===========================================================
+                  | DIFF:
+                  |===========================================================
+                  |${compareContents(actualLines, generatedLines)}
+                  |===========================================================
+                  | NEW CONTENTS:
+                  |===========================================================
+                  |${code}""".stripMargin
+
+    assert(false, msg)
+  }
+}