Merge pull request #5040 from adriaanm/rebase-5031

Merge 2.11.x into 2.12.x [ci: last-only]

Author: retronym

CONTRIBUTING.md

@@ -4,13 +4,13 @@ We follow the standard GitHub [fork & pull](https://help.github.com/articles/usi
 You're always welcome to submit your PR straight away and start the discussion (without reading the rest of this wonderful doc, or the `READMEnot^H^H^H.md`). The goal of these notes is to make your experience contributing to Scala as smooth and pleasant as possible. We're happy to guide you through the process once you've submitted your PR.
 
 ## The Scala Community
-In 2014, you -- the Scala community -- matched the core team at EPFL in number of commits contributed to Scala 2.11, doubling the percentage of commits from outside EPFL/Typesafe since 2.10. Excellent work! (The split was roughly 25/25/50 for you/EPFL/Typesafe.)
+In 2014, you -- the Scala community -- matched the core team at EPFL in number of commits contributed to Scala 2.11, doubling the percentage of commits from outside EPFL/Lightbend since 2.10. Excellent work! (The split was roughly 25/25/50 for you/EPFL/Lightbend.)
 
 We are super happy about this, and are eager to make your experience contributing to Scala productive and satisfying, so that we can keep up this growth. We can't do this alone (nor do we want to)!
 
 This is why we're collecting these notes on how to contribute, and we hope you'll share your experience to improve the process for the next contributor! (Feel free to send a PR for this note, send your thoughts to scala-internals, or tweet about it to @adriaanm.)
 
-By the way, the team at Lightbend (formerly Typesafe) is: @adriaanm, @lrytz, @retronym, @SethTisue, and @szeiger.
+By the way, the team at Lightbend is: @adriaanm, @lrytz, @retronym, @SethTisue, and @szeiger.
 
 ## What kind of PR are you submitting?
 

doc/LICENSE.md

@@ -4,7 +4,7 @@ Scala is licensed under the [BSD 3-Clause License](http://opensource.org/license
 
 Copyright (c) 2002-2016 EPFL
 
-Copyright (c) 2011-2016 Lightbend, Inc. (formerly Typesafe, Inc.)
+Copyright (c) 2011-2016 Lightbend, Inc.
 
 All rights reserved.
 

doc/License.rtf

@@ -11,7 +11,7 @@
 \fs40 \
 
 \fs26 Copyright (c) 2002-2016 EPFL\
-Copyright (c) 2011-2016 Lightbend, Inc. (formerly Typesafe, Inc.)\
+Copyright (c) 2011-2016 Lightbend, Inc.\
 All rights reserved.\
 \
 Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:\

project/build.properties

@@ -1 +1 @@
-sbt.version=0.13.9
+sbt.version=0.13.11

scripts/common

@@ -19,7 +19,7 @@ mkdir -p $IVY_CACHE
 rm -rf $IVY_CACHE/cache/org.scala-lang
 
 SBT_CMD=${sbtCmd-sbt}
-SBT_CMD="$SBT_CMD -sbt-version 0.13.9"
+SBT_CMD="$SBT_CMD -sbt-version 0.13.11"
 
 # temp dir where all 'non-build' operation are performed
 TMP_ROOT_DIR=$(mktemp -d -t pr-scala.XXXX)

src/compiler/scala/tools/nsc/typechecker/RefChecks.scala

@@ -1507,50 +1507,45 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
       }
     }
 
-    private def transformCaseApply(tree: Tree, ifNot: => Unit) = {
+    private def isSimpleCaseApply(tree: Tree): Boolean = {
       val sym = tree.symbol
-
       def isClassTypeAccessible(tree: Tree): Boolean = tree match {
         case TypeApply(fun, targs) =>
           isClassTypeAccessible(fun)
         case Select(module, apply) =>
           ( // SI-4859 `CaseClass1().InnerCaseClass2()` must not be rewritten to `new InnerCaseClass2()`;
             //          {expr; Outer}.Inner() must not be rewritten to `new Outer.Inner()`.
             treeInfo.isQualifierSafeToElide(module) &&
-            // SI-5626 Classes in refinement types cannot be constructed with `new`. In this case,
-            // the companion class is actually not a ClassSymbol, but a reference to an abstract type.
-            module.symbol.companionClass.isClass
-          )
+              // SI-5626 Classes in refinement types cannot be constructed with `new`. In this case,
+              // the companion class is actually not a ClassSymbol, but a reference to an abstract type.
+              module.symbol.companionClass.isClass
+            )
       }
 
-      val doTransform =
-        sym.isSourceMethod &&
+      sym.isSourceMethod &&
         sym.isCase &&
         sym.name == nme.apply &&
         isClassTypeAccessible(tree) &&
-        !tree.tpe.resultType.typeSymbol.primaryConstructor.isLessAccessibleThan(tree.symbol)
-
-      if (doTransform) {
-        def loop(t: Tree): Unit = t match {
-          case Ident(_) =>
-            checkUndesiredProperties(t.symbol, t.pos)
-          case Select(qual, _) =>
-            checkUndesiredProperties(t.symbol, t.pos)
-            loop(qual)
-          case _ =>
-        }
-        tree foreach {
-          case i@Ident(_) =>
-            enterReference(i.pos, i.symbol) // SI-5390 need to `enterReference` for `a` in `a.B()`
-          case _ =>
-        }
-        loop(tree)
-        toConstructor(tree.pos, tree.tpe)
+        !tree.tpe.finalResultType.typeSymbol.primaryConstructor.isLessAccessibleThan(tree.symbol)
+    }
+
+    private def transformCaseApply(tree: Tree) = {
+      def loop(t: Tree): Unit = t match {
+        case Ident(_) =>
+          checkUndesiredProperties(t.symbol, t.pos)
+        case Select(qual, _) =>
+          checkUndesiredProperties(t.symbol, t.pos)
+          loop(qual)
+        case _ =>
       }
-      else {
-        ifNot
-        tree
+
+      tree foreach {
+        case i@Ident(_) =>
+          enterReference(i.pos, i.symbol) // SI-5390 need to `enterReference` for `a` in `a.B()`
+        case _ =>
       }
+      loop(tree)
+      toConstructor(tree.pos, tree.tpe)
     }
 
     private def transformApply(tree: Apply): Tree = tree match {
@@ -1590,12 +1585,24 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
         // term should have been eliminated by super accessors
         assert(!(qual.symbol.isTrait && sym.isTerm && mix == tpnme.EMPTY), (qual.symbol, sym, mix))
 
-      transformCaseApply(tree,
+      // Rewrite eligible calls to monomorphic case companion apply methods to the equivalent constructor call.
+      //
+      // Note: for generic case classes the rewrite needs to be handled at the enclosing `TypeApply` to transform
+      // `TypeApply(Select(C, apply), targs)` to `Select(New(C[targs]), <init>)`. In case such a `TypeApply`
+      // was deemed ineligible for transformation (e.g. the case constructor was private), the refchecks transform
+      // will recurse to this point with `Select(C, apply)`, which will have a type `[T](...)C[T]`.
+      //
+      // We don't need to perform the check on the Select node, and `!isHigherKinded will guard against this
+      // redundant (and previously buggy, SI-9546) consideration.
+      if (!tree.tpe.isHigherKinded && isSimpleCaseApply(tree)) {
+        transformCaseApply(tree)
+      } else {
         qual match {
           case Super(_, mix)  => checkSuper(mix)
           case _              =>
         }
-      )
+        tree
+      }
     }
     private def transformIf(tree: If): Tree = {
       val If(cond, thenpart, elsepart) = tree
@@ -1720,7 +1727,10 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
 
           case TypeApply(fn, args) =>
             checkBounds(tree, NoPrefix, NoSymbol, fn.tpe.typeParams, args map (_.tpe))
-            transformCaseApply(tree, ())
+            if (isSimpleCaseApply(tree))
+              transformCaseApply(tree)
+            else
+              tree
 
           case x @ Apply(_, _)  =>
             transformApply(x)
@@ -1739,12 +1749,11 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
 
           case Ident(name) =>
             checkUndesiredProperties(sym, tree.pos)
-            transformCaseApply(tree,
-              if (name != nme.WILDCARD && name != tpnme.WILDCARD_STAR) {
-                assert(sym != NoSymbol, "transformCaseApply: name = " + name.debugString + " tree = " + tree + " / " + tree.getClass) //debug
-                enterReference(tree.pos, sym)
-              }
-            )
+            if (name != nme.WILDCARD && name != tpnme.WILDCARD_STAR) {
+              assert(sym != NoSymbol, "transformCaseApply: name = " + name.debugString + " tree = " + tree + " / " + tree.getClass) //debug
+              enterReference(tree.pos, sym)
+            }
+            tree
 
           case x @ Select(_, _) =>
             transformSelect(x)