Disallow old anonymous extension syntax

odersky · odersky · commit 0933b9c1b587 · 2019-11-16T15:42:25.000+01:00
Disallow the previous syntax
```
  given (x: T)
    ... extension methods
```
Require instead
```
  given extension (x: T)
    ... extension methods
```
This avoids the confusion with given instances for types in parentheses and makes
i7515.scala compile. To allow building with 0.20rc1, we allow the old extension syntax
if it comes with a name. E.g. the following is still allowed, but will be dropped
once we have bootstrapped with this commit present.
```
  given ops: (x: T)
    ... extension methods
```
diff --git a/compiler/src/dotty/tools/dotc/core/Contexts.scala b/compiler/src/dotty/tools/dotc/core/Contexts.scala
@@ -596,7 +596,7 @@ object Contexts {
     def setDebug: this.type = setSetting(base.settings.Ydebug, true)
   }
 
-  given (c: Context)
+  given ops: (c: Context)
     def addNotNullInfo(info: NotNullInfo) =
       c.withNotNullInfos(c.notNullInfos.extendWith(info))
 
diff --git a/compiler/src/dotty/tools/dotc/core/Definitions.scala b/compiler/src/dotty/tools/dotc/core/Definitions.scala
@@ -92,7 +92,7 @@ class Definitions {
    *  ImplicitFunctionN traits follow this template:
    *
    *      trait ImplicitFunctionN[T0,...,T{N-1}, R] extends Object {
-   *        def apply given ($x0: T0, ..., $x{N_1}: T{N-1}): R
+   *        def apply(given $x0: T0, ..., $x{N_1}: T{N-1}): R
    *      }
    *
    *  ErasedFunctionN traits follow this template:
diff --git a/compiler/src/dotty/tools/dotc/core/tasty/TastyFormat.scala b/compiler/src/dotty/tools/dotc/core/tasty/TastyFormat.scala
@@ -167,7 +167,7 @@ Standard-Section: "ASTs" TopLevelStat*
                   POLYtype       Length result_Type NamesTypes                     -- A polymorphic method type `[NamesTypes]result`, used in refinements
                   METHODtype     Length result_Type NamesTypes                     -- A method type `(NamesTypes)result`, needed for refinements
                   ERASEDMETHODtype      Length result_Type NamesTypes              -- A method type `erased (NamesTypes)result`, needed for refinements
-                  GIVENMETHODtype       Length result_Type NamesTypes              -- A method type `given (NamesTypes)result`, needed for refinements
+                  GIVENMETHODtype       Length result_Type NamesTypes              -- A method type `(given NamesTypes)result`, needed for refinements
                   ERASEDGIVENMETHODtype Length result_Type NamesTypes              -- A method type `given(erased NamesTypes)result`, needed for refinements
                   IMPLICITMETHODtype    Length result_Type NamesTypes              -- A method type `(implicit NamesTypes)result`, needed for refinements
   // TODO: remove ERASEDIMPLICITMETHODtype
diff --git a/compiler/src/dotty/tools/dotc/parsing/Parsers.scala b/compiler/src/dotty/tools/dotc/parsing/Parsers.scala
@@ -3442,7 +3442,7 @@ object Parsers {
               if isExtension then
                 checkExtensionParams(paramsStart, vparamss)
 
-          parseParams(isExtension = !hasGivenSig)
+          parseParams(isExtension = false)
           val parents =
             if in.token == COLON then
               in.nextToken()
diff --git a/compiler/src/dotty/tools/dotc/typer/Nullables.scala b/compiler/src/dotty/tools/dotc/typer/Nullables.scala
@@ -137,7 +137,7 @@ object Nullables with
     // TODO: Add constant pattern if the constant type is not nullable
     case _ => false
 
-  given (infos: List[NotNullInfo])
+  given notNullInfoOps: (infos: List[NotNullInfo])
 
     /** Do the current not-null infos imply that `ref` is not null?
      *  Not-null infos are as a history where earlier assertions and retractions replace
@@ -161,7 +161,7 @@ object Nullables with
       then infos
       else info :: infos
 
-  given (tree: Tree)
+  given treeOps: (tree: Tree)
 
     /* The `tree` with added nullability attachment */
     def withNotNullInfo(info: NotNullInfo): tree.type =
@@ -251,7 +251,7 @@ object Nullables with
           tree.computeNullable()
       }.traverse(tree)
 
-  given (tree: Assign)
+  given assignOps: (tree: Assign)
     def computeAssignNullable()(given Context): tree.type = tree.lhs match
       case TrackedRef(ref) =>
         tree.withNotNullInfo(NotNullInfo(Set(), Set(ref))) // TODO: refine with nullability type info
diff --git a/docs/docs/reference/changed-features/numeric-literals.md b/docs/docs/reference/changed-features/numeric-literals.md
@@ -201,7 +201,7 @@ no code that can be executed at runtime. That's why we define an intermediary cl
 method in the `FromDigits` given instance. That method is defined in terms of a macro
 implementation method `fromDigitsImpl`. Here is its definition:
 ```scala
-  private def fromDigitsImpl(digits: Expr[String]) given (ctx: QuoteContext): Expr[BigFloat] =
+  private def fromDigitsImpl(digits: Expr[String])(given ctx: QuoteContext): Expr[BigFloat] =
     digits match {
       case Const(ds) =>
         try {
diff --git a/docs/docs/reference/contextual/relationship-implicits.md b/docs/docs/reference/contextual/relationship-implicits.md
@@ -21,7 +21,7 @@ Given instances can be mapped to combinations of implicit objects, classes and i
     ```
  2. Parameterized given instances are mapped to combinations of classes and implicit methods. E.g.,
     ```scala
-      given listOrd[T](given (ord: Ord[T]): Ord[List[T]] { ... }
+      given listOrd[T](given ord: Ord[T]): Ord[List[T]] { ... }
     ```
     maps to
     ```scala
diff --git a/docs/docs/reference/metaprogramming/macros.md b/docs/docs/reference/metaprogramming/macros.md
@@ -170,7 +170,7 @@ quote but no splice between the parameter binding of `T` and its
 usage. But the code can be made phase correct by adding a binding
 of a `Type[T]` tag:
 ```scala
-def reflect[T, U](f: Expr[T] => Expr[U]) given (t: Type[T]): Expr[T => U] =
+def reflect[T, U](f: Expr[T] => Expr[U])(given t: Type[T]): Expr[T => U] =
   '{ (x: $t) => ${ f('x) } }
 ```
 In this version of `reflect`, the type of `x` is now the result of
diff --git a/docs/docs/reference/other-new-features/tupled-function.md b/docs/docs/reference/other-new-features/tupled-function.md
@@ -28,7 +28,7 @@ The compiler will synthesize an instance of `TupledFunction[F, G]` if:
 * `F` is a function type of arity `N`
 * `G` is a function with a single tuple argument of size `N` and it's types are equal to the arguments of `F`
 * The return type of `F` is equal to the return type of `G`
-* `F` and `G` are the same kind of function (both are `(...) => R` or both are `given (...) => R`)
+* `F` and `G` are the same kind of function (both are `(...) => R` or both are `(given ...) => R`)
 * If only one of `F` or `G` is instantiated the second one is inferred.
 
 Examples
@@ -43,7 +43,7 @@ Examples
  *  @tparam Args the tuple type with the same types as the function arguments of F
  *  @tparam R the return type of F
  */
-def (f: F) tupled[F, Args <: Tuple, R] given (tf: TupledFunction[F, Args => R]): Args => R = tf.tupled(f)
+def (f: F) tupled[F, Args <: Tuple, R](given tf: TupledFunction[F, Args => R]): Args => R = tf.tupled(f)
 ```
 
 `TupledFunction` can be used to generalize the `Function.untupled` methods to functions of any arities ([full example](https://github.com/lampepfl/dotty/blob/master/tests/run/tupled-function-untupled.scala))
@@ -58,7 +58,7 @@ def (f: F) tupled[F, Args <: Tuple, R] given (tf: TupledFunction[F, Args => R]):
  *  @tparam Args the tuple type with the same types as the function arguments of F
  *  @tparam R the return type of F
  */
-def (f: Args => R) untupled[F, Args <: Tuple, R] given (tf: TupledFunction[F, Args => R]): F = tf.untupled(f)
+def (f: Args => R) untupled[F, Args <: Tuple, R](given tf: TupledFunction[F, Args => R]): F = tf.untupled(f)
 ```
 
 `TupledFunction` can also be used to generalize the [`Tuple1.compose`](https://github.com/lampepfl/dotty/blob/master/tests/run/tupled-function-compose.scala) and [`Tuple1.andThen`](https://github.com/lampepfl/dotty/blob/master/tests/run/tupled-function-andThen.scala) methods to compose functions of larger arities and with functions that return tuples.
@@ -72,7 +72,7 @@ def (f: Args => R) untupled[F, Args <: Tuple, R] given (tf: TupledFunction[F, Ar
  *  @tparam GArgs the tuple type with the same types as the function arguments of G
  *  @tparam R the return type of F
  */
-def (f: F) compose[F, G, FArgs <: Tuple, GArgs <: Tuple, R](g: G) given (tg: TupledFunction[G, GArgs => FArgs], tf: TupledFunction[F, FArgs => R]): GArgs => R = {
+def (f: F) compose[F, G, FArgs <: Tuple, GArgs <: Tuple, R](g: G)(given tg: TupledFunction[G, GArgs => FArgs], tf: TupledFunction[F, FArgs => R]): GArgs => R = {
   (x: GArgs) => tf.tupled(f)(tg.tupled(g)(x))
 }
 ```
diff --git a/library/src/scala/tasty/reflect/CommentOps.scala b/library/src/scala/tasty/reflect/CommentOps.scala
@@ -2,7 +2,7 @@ package scala.tasty.reflect
 
 trait CommentOps extends Core {
 
-  given (self: Comment) {
+  given CommentOps: (self: Comment) {
 
     /** Raw comment string */
     def raw: String = internal.Comment_raw(self)
diff --git a/library/src/scala/tasty/reflect/ConstantOps.scala b/library/src/scala/tasty/reflect/ConstantOps.scala
@@ -3,7 +3,7 @@ package reflect
 
 trait ConstantOps extends Core {
 
-  given (const: Constant) {
+  given ConstantOps: (const: Constant) {
     def value: Any = internal.Constant_value(const)
   }
 
diff --git a/library/src/scala/tasty/reflect/ContextOps.scala b/library/src/scala/tasty/reflect/ContextOps.scala
@@ -3,7 +3,7 @@ package reflect
 
 trait ContextOps extends Core {
 
-  given (self: Context) {
+  given ContextOps: (self: Context) {
     /** Returns the owner of the context */
     def owner: Symbol = internal.Context_owner(self)
 
diff --git a/library/src/scala/tasty/reflect/FlagsOps.scala b/library/src/scala/tasty/reflect/FlagsOps.scala
@@ -2,7 +2,7 @@ package scala.tasty.reflect
 
 trait FlagsOps extends Core {
 
-  given (self: Flags) {
+  given FlagsOps: (self: Flags) {
 
     /** Is the given flag set a subset of this flag sets */
     def is(that: Flags): Boolean = internal.Flags_is(self)(that)
diff --git a/library/src/scala/tasty/reflect/IdOps.scala b/library/src/scala/tasty/reflect/IdOps.scala
@@ -3,7 +3,7 @@ package reflect
 
 trait IdOps extends Core {
 
-  given (id: Id) {
+  given IsOps: (id: Id) {
 
     /** Position in the source code */
     def pos(given ctx: Context): Position = internal.Id_pos(id)
diff --git a/library/src/scala/tasty/reflect/ImplicitsOps.scala b/library/src/scala/tasty/reflect/ImplicitsOps.scala
@@ -10,7 +10,7 @@ trait ImplicitsOps extends Core {
       internal.matchImplicitSearchSuccess(isr)
   }
 
-  given (self: ImplicitSearchSuccess) {
+  given successOps: (self: ImplicitSearchSuccess) {
     def tree(given ctx: Context): Term = internal.ImplicitSearchSuccess_tree(self)
   }
 
@@ -19,7 +19,7 @@ trait ImplicitsOps extends Core {
       internal.matchImplicitSearchFailure(isr)
   }
 
-  given (self: ImplicitSearchFailure) {
+  given failureOps: (self: ImplicitSearchFailure) {
     def explanation(given ctx: Context): String = internal.ImplicitSearchFailure_explanation(self)
   }
 
diff --git a/library/src/scala/tasty/reflect/ImportSelectorOps.scala b/library/src/scala/tasty/reflect/ImportSelectorOps.scala
@@ -3,7 +3,7 @@ package reflect
 
 trait ImportSelectorOps extends Core {
 
-  given (self: SimpleSelector) {
+  given SimpleSelectorOps: (self: SimpleSelector) {
     def selection(given ctx: Context): Id =
       internal.SimpleSelector_selection(self)
   }
@@ -13,7 +13,7 @@ trait ImportSelectorOps extends Core {
       internal.matchSimpleSelector(importSelector).map(_.selection)
   }
 
-  given (self: RenameSelector) {
+  given RenameSelectorOps: (self: RenameSelector) {
     def from(given ctx: Context): Id =
       internal.RenameSelector_from(self)
 
@@ -26,7 +26,7 @@ trait ImportSelectorOps extends Core {
       internal.matchRenameSelector(importSelector).map(x => (x.from, x.to))
   }
 
-  given (self: OmitSelector) {
+  given OmitSelectorOps: (self: OmitSelector) {
     def omitted(given ctx: Context): Id =
       internal.SimpleSelector_omitted(self)
   }
diff --git a/library/src/scala/tasty/reflect/PositionOps.scala b/library/src/scala/tasty/reflect/PositionOps.scala
@@ -2,7 +2,7 @@ package scala.tasty.reflect
 
 trait PositionOps extends Core {
 
-  given (pos: Position) {
+  given PositionOps: (pos: Position) {
 
     /** The start offset in the source file */
     def start: Int = internal.Position_start(pos)
@@ -33,7 +33,7 @@ trait PositionOps extends Core {
 
   }
 
-  given (sourceFile: SourceFile) {
+  given SourceFileOps: (sourceFile: SourceFile) {
 
     /** Path to this source file */
     def jpath: java.nio.file.Path = internal.SourceFile_jpath(sourceFile)
diff --git a/library/src/scala/tasty/reflect/SignatureOps.scala b/library/src/scala/tasty/reflect/SignatureOps.scala
@@ -9,7 +9,7 @@ trait SignatureOps extends Core {
       Some((sig.paramSigs, sig.resultSig))
   }
 
-  given (sig: Signature) {
+  given SignatureOps: (sig: Signature) {
 
     /** The signatures of the method parameters.
       *
diff --git a/library/src/scala/tasty/reflect/SymbolOps.scala b/library/src/scala/tasty/reflect/SymbolOps.scala
@@ -14,7 +14,7 @@ trait SymbolOps extends Core { selfSymbolOps: FlagsOps =>
       internal.Symbol_noSymbol
   }
 
-  given (self: Symbol) {
+  given SymbolOps: (self: Symbol) {
 
     /** Owner of this symbol. The owner is the symbol in which this symbol is defined */
     def owner(given ctx: Context): Symbol = internal.Symbol_owner(self)
diff --git a/library/src/scala/tasty/reflect/TreeOps.scala b/library/src/scala/tasty/reflect/TreeOps.scala
diff --git a/library/src/scala/tasty/reflect/TypeOrBoundsOps.scala b/library/src/scala/tasty/reflect/TypeOrBoundsOps.scala
diff --git a/tests/neg/extension-methods.scala b/tests/neg/extension-methods.scala
diff --git a/tests/neg/i5455.scala b/tests/neg/i5455.scala
diff --git a/tests/pos/i7515.scala b/tests/pos/i7515.scala
diff --git a/tests/pos/matrixOps.scala b/tests/pos/matrixOps.scala
diff --git a/tests/pos/reference/delegates.scala b/tests/pos/reference/delegates.scala
diff --git a/tests/run/extmethods2.scala b/tests/run/extmethods2.scala

Original file line number	Diff line number	Diff line change
`@@ -596,7 +596,7 @@ object Contexts {`
`596`	`596`	`def setDebug: this.type = setSetting(base.settings.Ydebug, true)`
`597`	`597`	`}`
`598`	`598`
`599`		`- given (c: Context)`
	`599`	`+ given ops: (c: Context)`
`600`	`600`	`def addNotNullInfo(info: NotNullInfo) =`
`601`	`601`	`c.withNotNullInfos(c.notNullInfos.extendWith(info))`
`602`	`602`
Original file line number	Diff line number	Diff line change
`@@ -92,7 +92,7 @@ class Definitions {`
`92`	`92`	`* ImplicitFunctionN traits follow this template:`
`93`	`93`	`*`
`94`	`94`	`* trait ImplicitFunctionN[T0,...,T{N-1}, R] extends Object {`
`95`		`- * def apply given ($x0: T0, ..., $x{N_1}: T{N-1}): R`
	`95`	`+ * def apply(given $x0: T0, ..., $x{N_1}: T{N-1}): R`
`96`	`96`	`* }`
`97`	`97`	`*`
`98`	`98`	`* ErasedFunctionN traits follow this template:`