Convert tests to use new type pattern syntax

Convert many existing occurrences of `t` as a type pattern
variable to `type t`.

Author: odersky

compiler/src/dotty/tools/dotc/parsing/Parsers.scala

@@ -1805,14 +1805,12 @@ object Parsers {
 
     /** ClsTypeParamClause::=  `[' ClsTypeParam {`,' ClsTypeParam} `]'
      *  ClsTypeParam      ::=  {Annotation} [`+' | `-'] TypeParamCore
-     *
      *  DefTypeParamClause::=  `[' DefTypeParam {`,' DefTypeParam} `]'
      *  DefTypeParam      ::=  {Annotation} TypeParamCore
      *  TypeParamCore     ::=  id [HkTypeParamClause] TypeParamBounds
      *
      *  TypTypeParamCaluse::=  `[' TypTypeParam {`,' TypTypeParam} `]'
      *  TypTypeParam      ::=  {Annotation} id [HkTypePamClause] TypeBounds
-     *
      *  HkTypeParamClause ::=  `[' HkTypeParam {`,' HkTypeParam} `]'
      *  HkTypeParam       ::=  {Annotation} ['+' | `-'] (id [HkTypePamClause] | _') TypeBounds
      */

docs/docs/internals/syntax.md

@@ -242,14 +242,14 @@ SimplePattern1    ::=  Path
                     |  SimplePattern1 ‘.’ id
 PatVar            ::=  varid
                     |  ‘_’
-BindingTypePattern::=  Type
 TypePattern       ::=  RefinedType
 Patterns          ::=  Pattern {‘,’ Pattern}
 ArgumentPatterns  ::=  ‘(’ [Patterns] ‘)’                                       Apply(fn, pats)
                     |  ‘(’ [Patterns ‘,’] Pattern2 ‘:’ ‘_’ ‘*’ ‘)’
 
 Augmentation      ::=  ‘augment’ BindingTypePattern
                        [[nl] ImplicitParamClause] TemplateClause                Augment(name, templ)
+BindingTypePattern::=  Type
 ```
 
 ### Type and Value Parameters

tests/neg-custom-args/i1754.scala

@@ -2,7 +2,7 @@ case class One[T](fst: T)
 
 object Test {
   def bad[T](e: One[T]) = e match {
-    case foo: One[a] =>
+    case foo: One[type A] =>
       val t: T = e.fst
       val nok: Nothing = t // error
   }

tests/neg/gadt-eval.scala

@@ -20,7 +20,7 @@ object Test {
   def eval2[T](e: Exp[T]): T = e match {
     case e: Lit =>
       e.value
-    case e: Pair[t1, t2] =>
+    case e: Pair[type t1, type t2] =>
       (eval(e.fst), eval(e.fst)) // error:
         //-- [E007] Type Mismatch Error: tests/neg/gadt-eval.scala:24:6 ------------------
         //24 |      (eval(e.fst), eval(e.fst))

tests/pos/escapes2.scala

@@ -1,5 +1,5 @@
 object Test {
   class C3[T](val elem: T)
   class D3[T](val elemD: T) extends C3[T](elemD)
-  def f[T](x: C3[T]) = x match { case d: D3[t] => d.elemD }
+  def f[T](x: C3[T]) = x match { case d: D3[type X] => d.elemD }
 }

tests/pos/exhaust_2.scala

@@ -44,7 +44,7 @@ object ExhaustivityWarnBugReportMinimal {
 
   val v2: (Some[_], Int) = (???, ???)
   v2 match {
-    case (x: Some[t], _) =>
+    case (x: Some[type t], _) =>
   }
 
   val v3: (Option[_], FoundNode[_]) = (???, ???)

tests/pos/existentials-harmful.scala

@@ -47,7 +47,7 @@ object ExistentialsConsideredHarmful {
   // Type annotation on bc is required ... possible compiler bug?
   // val bc : BoxCarrier[_ <: Animal] = aBox match {
   val bc = aBox match {
-    case tb : TransportBox[a] => new BoxCarrier(tb) {
+    case tb : TransportBox[type A] => new BoxCarrier(tb) {
       def speed: Int = 12
     }
   }

tests/pos/gadt-eval.scala

@@ -13,7 +13,7 @@ object Test {
   def eval2[T](e: Exp[T]): T = e match {
     case e: Lit =>
       e.value
-    case e: Pair[t1, t2] =>
+    case e: Pair[type T1, type T2] =>
       (eval(e.fst), eval(e.snd))
   }
 }

tests/pos/i0290-type-bind.scala

@@ -3,6 +3,9 @@ object foo{
   x match {
     case t: List[tt] => t.head.asInstanceOf[tt]
   }
+  x match {
+    case t: List[type tt] => t.head.asInstanceOf[tt]
+  }
 }
 
 object bar {
@@ -12,8 +15,8 @@ object bar {
   val x: AnyRef = new C
 
   x match {
-    case x: C[u] =>
-      def x: u = x
+    case x: C[type U] =>
+      def x: U = x
       val s: Seq[_] = x
   }
 }

tests/pos/i0306.scala

@@ -5,8 +5,8 @@ object bar {
   val x: AnyRef = new C
 
   val y = x match {
-    case x: C[u] =>
-      def xx: u = xx
+    case x: C[type U] =>
+      def xx: U = xx
       xx
   }
 

tests/pos/i1365.scala

@@ -10,4 +10,7 @@ class Test[A] {
   def g(cmd: Message[A]): Unit = cmd match {
     case s: Script[z] => s.iterator.foreach(x => g(x))
   }
+  def h(cmd: Message[A]): Unit = cmd match {
+    case s: Script[type Z] => s.iterator.foreach(x => g(x))
+  }
 }

tests/pos/i947.scala

@@ -6,8 +6,8 @@ object Test {
 
     override def equals(other: Any) = other match {
       case o: c => x == o.x
-      case xs: List[c] => false
-      case ys: List[d18383] => false
+      case xs: List[type C] => false
+      case ys: List[type d18383] => false
       case _ => false
     }
 

tests/pos/t4070.scala

@@ -1,7 +1,7 @@
 package a {
   // method before classes
   trait Foo {
-    def crash(x: Dingus[_]): Unit = x match { case m: Bippy[tv] => () }
+    def crash(x: Dingus[_]): Unit = x match { case m: Bippy[type tv] => () }
 
     class Dingus[T]
     class Bippy[CC[X] <: Seq[X]]() extends Dingus[CC[Int]]
@@ -14,7 +14,7 @@ package b {
     class Dingus[T]
     class Bippy[CC[X] <: Seq[X]]() extends Dingus[CC[Int]]
 
-    def crash(x: Dingus[_]): Unit = x match { case m: Bippy[tv] => () }
+    def crash(x: Dingus[_]): Unit = x match { case m: Bippy[type tv] => () }
   }
 }
 

tests/pos/t6205.scala

@@ -2,8 +2,8 @@
 class A[T]
 class Test1 {
   def x(backing: Map[A[_], Any]) =
-    for( (k: A[kt], v) <- backing)
-      yield (k: A[kt])
+    for( (k: A[type KT], v) <- backing)
+      yield (k: A[KT])
 }
 
 // this tests same thing as above, but independent of library classes,
@@ -13,6 +13,6 @@ class Mapped[A] { def map[T](f: Holder[A] => T): Iterable[T] = ??? }
 class Test2 {
   def works(backing: Mapped[A[_]]): Iterable[A[_]]
     = backing.map(x =>
-         x match {case Holder(k: A[kt]) => (k: A[kt])}
+         x match {case Holder(k: A[type KT]) => (k: A[KT])}
       )
 }

tests/pos/t6275.scala

@@ -5,7 +5,7 @@ final class B[T] extends A[T]
 object ParsedAxis {
   type BI = B[Int]
 
-  def f1(a: A[Int]) = a match { case b: B[Int] => 3 }
+  def f1(a: A[Int]) = a match { case b: B[type Int] => 3 }
   def f2(a: A[Int]) = a match { case b: BI => 3 }
   def f3(a: A[Int]) = a match { case b: B[t] => 3 }
 }

tests/pos/t8023.scala

@@ -3,7 +3,7 @@ class D[K]
 
 object Test3 {
   def foo = (null: Any) match {
-    case a: C[k] => new C[k]() // this one worked before as the info of `A` was complete
+    case a: C[type K] => new C[K]() // this one worked before as the info of `A` was complete
     // ()
   }
 }

tests/pos/t946.scala

@@ -3,6 +3,6 @@ object pmbugbounds {
   class Foo[t <: Bar] {}
 
   (new Foo[Bar]) match {
-    case _ : Foo[x] => null
+    case _ : Foo[type X] => null
   }
 }