Reorganize retains annotation classes

odersky · odersky · commit 30a53efff9aa · 2022-08-29T14:42:53.000+02:00
Since they are just backup syntax, no need to put them in the scala package.
diff --git a/compiler/src/dotty/tools/dotc/ast/Desugar.scala b/compiler/src/dotty/tools/dotc/ast/Desugar.scala
@@ -1813,7 +1813,7 @@ object desugar {
         // convert   `{refs} T`   to `T @retains refs`
         //           `{refs}-> T` to `-> (T @retainsByName refs)`
         def annotate(annotName: TypeName, tp: Tree) =
-          Annotated(tp, New(scalaDot(annotName), List(refs)))
+          Annotated(tp, New(scalaAnnotationDot(annotName), List(refs)))
         parent match
           case ByNameTypeTree(restpt) =>
             cpy.ByNameTypeTree(parent)(annotate(tpnme.retainsByName, restpt))
diff --git a/compiler/src/dotty/tools/dotc/core/Definitions.scala b/compiler/src/dotty/tools/dotc/core/Definitions.scala
@@ -1017,8 +1017,8 @@ class Definitions {
   @tu lazy val VarargsAnnot: ClassSymbol = requiredClass("scala.annotation.varargs")
   @tu lazy val SinceAnnot: ClassSymbol = requiredClass("scala.annotation.since")
   @tu lazy val RequiresCapabilityAnnot: ClassSymbol = requiredClass("scala.annotation.internal.requiresCapability")
-  @tu lazy val RetainsAnnot: ClassSymbol = requiredClass("scala.retains")
-  @tu lazy val RetainsByNameAnnot: ClassSymbol = requiredClass("scala.retainsByName")
+  @tu lazy val RetainsAnnot: ClassSymbol = requiredClass("scala.annotation.retains")
+  @tu lazy val RetainsByNameAnnot: ClassSymbol = requiredClass("scala.annotation.retainsByName")
 
   @tu lazy val JavaRepeatableAnnot: ClassSymbol = requiredClass("java.lang.annotation.Repeatable")
 
diff --git a/library/src-bootstrapped/scala/Retains.scala b/library/src-bootstrapped/scala/Retains.scala
diff --git a/library/src-bootstrapped/scala/annotation/retains.scala b/library/src-bootstrapped/scala/annotation/retains.scala
@@ -0,0 +1,15 @@
+package scala.annotation
+
+/** An annotation that indicates capture of a set of references under -Ycc.
+ *
+ *      T @retains(x, y, z)
+ *
+ *  is the internal representation used for the capturing type
+ *
+ *      {x, y, z}  T
+ *
+ *  The annotation can also be written explicitly if one wants to avoid the
+ *  non-standard capturing type syntax.
+ */
+@experimental class retains(xs: Any*) extends annotation.StaticAnnotation
+
diff --git a/library/src-bootstrapped/scala/annotation/retainsByName.scala b/library/src-bootstrapped/scala/annotation/retainsByName.scala
@@ -1,5 +1,4 @@
-package scala
-import annotation.experimental
+package scala.annotation
 
 /** An annotation that indicates capture of an enclosing by-name type
  */
diff --git a/tests/neg-custom-args/captures/capt-depfun.scala b/tests/neg-custom-args/captures/capt-depfun.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 type Cap = C @retains(*)
 
diff --git a/tests/neg-custom-args/captures/capt-depfun2.scala b/tests/neg-custom-args/captures/capt-depfun2.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 type Cap = C @retains(*)
 
diff --git a/tests/neg-custom-args/captures/capt-test.scala b/tests/neg-custom-args/captures/capt-test.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 import language.experimental.erasedDefinitions
 
 class CT[E <: Exception]
diff --git a/tests/neg-custom-args/captures/capt-wf-typer.scala b/tests/neg-custom-args/captures/capt-wf-typer.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 type Cap = {*} C
 
diff --git a/tests/neg-custom-args/captures/capt1.check b/tests/neg-custom-args/captures/capt1.check
@@ -1,51 +1,51 @@
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:3:2 ------------------------------------------
-3 |  () => if x == null then y else y  // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:4:2 ------------------------------------------
+4 |  () => if x == null then y else y  // error
   |  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |  Found:    {x} () -> ? C
   |  Required: () -> C
   |
   | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:6:2 ------------------------------------------
-6 |  () => if x == null then y else y  // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:7:2 ------------------------------------------
+7 |  () => if x == null then y else y  // error
   |  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |  Found:    {x} () -> ? C
   |  Required: Matchable
   |
   | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:13:2 -----------------------------------------
-13 |  def f(y: Int) = if x == null then y else y  // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:14:2 -----------------------------------------
+14 |  def f(y: Int) = if x == null then y else y  // error
    |  ^
    |  Found:    {x} Int -> Int
    |  Required: Matchable
-14 |  f
+15 |  f
    |
    | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:20:2 -----------------------------------------
-20 |  class F(y: Int) extends A:   // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:21:2 -----------------------------------------
+21 |  class F(y: Int) extends A:   // error
    |  ^
    |  Found:    {x} A
    |  Required: A
-21 |    def m() = if x == null then y else y
-22 |  F(22)
+22 |    def m() = if x == null then y else y
+23 |  F(22)
    |
    | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:25:2 -----------------------------------------
-25 |  new A: // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:26:2 -----------------------------------------
+26 |  new A: // error
    |  ^
    |  Found:    {x} A
    |  Required: A
-26 |    def m() = if x == null then y else y
+27 |    def m() = if x == null then y else y
    |
    | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:31:24 ----------------------------------------
-31 |  val z2 = h[() -> Cap](() => x) // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:32:24 ----------------------------------------
+32 |  val z2 = h[() -> Cap](() => x) // error
    |                        ^^^^^^^
    |                        Found:    {x} () -> {*} C
    |                        Required: () -> box {*} C
    |
    | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:32:5 -----------------------------------------
-32 |    (() => C())  // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/capt1.scala:33:5 -----------------------------------------
+33 |    (() => C())  // error
    |     ^^^^^^^^^
    |     Found:    ? () -> {*} C
    |     Required: () -> box {*} C
diff --git a/tests/neg-custom-args/captures/capt1.scala b/tests/neg-custom-args/captures/capt1.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 def f(x: C @retains(*), y: C): () -> C =
   () => if x == null then y else y  // error
diff --git a/tests/neg-custom-args/captures/capt3.scala b/tests/neg-custom-args/captures/capt3.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 type Cap = C @retains(*)
 
diff --git a/tests/neg-custom-args/captures/cc1.scala b/tests/neg-custom-args/captures/cc1.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 object Test:
 
   def f[A <: Matchable @retains(*)](x: A): Matchable = x // error
diff --git a/tests/neg-custom-args/captures/io.scala b/tests/neg-custom-args/captures/io.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 sealed trait IO:
   def puts(msg: Any): Unit = println(msg)
 
diff --git a/tests/neg-custom-args/captures/try.check b/tests/neg-custom-args/captures/try.check
@@ -1,42 +1,42 @@
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/try.scala:22:49 ------------------------------------------
-22 |  val a = handle[Exception, CanThrow[Exception]] { // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/try.scala:23:49 ------------------------------------------
+23 |  val a = handle[Exception, CanThrow[Exception]] { // error
    |                                                 ^
    |                              Found:    ? ({*} CT[Exception]) -> {*} CT[? >: box ? Exception <: box ? Exception]
    |                              Required: CanThrow[Exception] => box {*} CT[Exception]
-23 |    (x: CanThrow[Exception]) => x
-24 |  }{
+24 |    (x: CanThrow[Exception]) => x
+25 |  }{
    |
    | longer explanation available when compiling with `-explain`
--- [E007] Type Mismatch Error: tests/neg-custom-args/captures/try.scala:28:43 ------------------------------------------
-28 |  val b = handle[Exception, () -> Nothing] {  // error
+-- [E007] Type Mismatch Error: tests/neg-custom-args/captures/try.scala:29:43 ------------------------------------------
+29 |  val b = handle[Exception, () -> Nothing] {  // error
    |                                           ^
    |                                           Found:    ? (x: {*} CT[Exception]) -> {x} () -> ? Nothing
    |                                           Required: CanThrow[Exception] => () -> Nothing
-29 |    (x: CanThrow[Exception]) => () => raise(new Exception)(using x)
-30 |  } {
+30 |    (x: CanThrow[Exception]) => () => raise(new Exception)(using x)
+31 |  } {
    |
    | longer explanation available when compiling with `-explain`
--- Error: tests/neg-custom-args/captures/try.scala:39:4 ----------------------------------------------------------------
-34 |  val xx = handle {
-35 |    (x: CanThrow[Exception]) =>
-36 |      () =>
-37 |        raise(new Exception)(using x)
-38 |        22
-39 |  } {  // error
+-- Error: tests/neg-custom-args/captures/try.scala:40:4 ----------------------------------------------------------------
+35 |  val xx = handle {
+36 |    (x: CanThrow[Exception]) =>
+37 |      () =>
+38 |        raise(new Exception)(using x)
+39 |        22
+40 |  } {  // error
    |           ^
    |           The expression's type box {*} () -> Int is not allowed to capture the root capability `*`.
    |           This usually means that a capability persists longer than its allowed lifetime.
-40 |    (ex: Exception) => () => 22
-41 |  }
--- Error: tests/neg-custom-args/captures/try.scala:51:2 ----------------------------------------------------------------
-46 |val global = handle {
-47 |  (x: CanThrow[Exception]) =>
-48 |    () =>
-49 |      raise(new Exception)(using x)
-50 |      22
-51 |} {  // error
+41 |    (ex: Exception) => () => 22
+42 |  }
+-- Error: tests/neg-custom-args/captures/try.scala:52:2 ----------------------------------------------------------------
+47 |val global = handle {
+48 |  (x: CanThrow[Exception]) =>
+49 |    () =>
+50 |      raise(new Exception)(using x)
+51 |      22
+52 |} {  // error
    |             ^
    |             The expression's type box {*} () -> Int is not allowed to capture the root capability `*`.
    |             This usually means that a capability persists longer than its allowed lifetime.
-52 |  (ex: Exception) => () => 22
-53 |}
+53 |  (ex: Exception) => () => 22
+54 |}
diff --git a/tests/neg-custom-args/captures/try.scala b/tests/neg-custom-args/captures/try.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 import language.experimental.erasedDefinitions
 
 class CT[E <: Exception]
diff --git a/tests/pos-custom-args/captures/boxmap.scala b/tests/pos-custom-args/captures/boxmap.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 type Top = Any @retains(*)
 
 type Box[+T <: Top] = ([K <: Top] -> (T => K) -> K)
diff --git a/tests/pos-custom-args/captures/byname.scala b/tests/pos-custom-args/captures/byname.scala
@@ -1,3 +1,4 @@
+import annotation.retainsByName
 class CC
 type Cap = {*} CC
 
@@ -7,4 +8,6 @@ def test(cap1: Cap, cap2: Cap): {cap1} I =
   def f() = if cap1 == cap1 then I() else I()
   def h(x: {cap1}-> I) = x
   h(f()) // OK
+  def hh(x: -> I @retainsByName(cap1)) = x
+  h(f())
 
diff --git a/tests/pos-custom-args/captures/capt-depfun.scala b/tests/pos-custom-args/captures/capt-depfun.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 type Cap = C @retains(*)
 
diff --git a/tests/pos-custom-args/captures/capt-depfun2.scala b/tests/pos-custom-args/captures/capt-depfun2.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class C
 type Cap = C @retains(*)
 
diff --git a/tests/pos-custom-args/captures/capt0.scala b/tests/pos-custom-args/captures/capt0.scala
@@ -2,6 +2,6 @@ object Test:
 
   def test() =
     val x: {*} Any = "abc"
-    val y: Object @scala.retains(x) = ???
-    val z: Object @scala.retains(x, *) = y: Object @scala.retains(x)
+    val y: Object @scala.annotation.retains(x) = ???
+    val z: Object @scala.annotation.retains(x, *) = y: Object @annotation.retains(x)
 
diff --git a/tests/pos-custom-args/captures/capt2.scala b/tests/pos-custom-args/captures/capt2.scala
@@ -1,4 +1,4 @@
-import scala.retains
+import annotation.retains
 class C
 type Cap = C @retains(*)
 
diff --git a/tests/pos-custom-args/captures/cc-expand.scala b/tests/pos-custom-args/captures/cc-expand.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 object Test:
 
   class A
diff --git a/tests/pos-custom-args/captures/classes.scala b/tests/pos-custom-args/captures/classes.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 class B
 type Cap = {*} B
 class C(val n: Cap):
diff --git a/tests/pos-custom-args/captures/list-encoding.scala b/tests/pos-custom-args/captures/list-encoding.scala
@@ -1,4 +1,5 @@
 package listEncoding
+import annotation.retains
 
 class Cap
 
diff --git a/tests/pos-custom-args/captures/try.scala b/tests/pos-custom-args/captures/try.scala
@@ -1,3 +1,4 @@
+import annotation.retains
 import language.experimental.erasedDefinitions
 
 class CT[E <: Exception]

Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,4 @@`
	`1`	`+import annotation.retains`
`1`	`2`	`class C`
`2`	`3`	`type Cap = C @retains(*)`
`3`	`4`
Original file line number	Diff line number	Diff line change
`@@ -1,3 +1,4 @@`
	`1`	`+import annotation.retains`
`1`	`2`	`import language.experimental.erasedDefinitions`
`2`	`3`
`3`	`4`	`class CT[E <: Exception]`