Make NamedTuples a standard feature again in 3.7

Author: WojciechMazur

compiler/src/dotty/tools/dotc/config/Feature.scala

@@ -33,7 +33,6 @@ object Feature:
   val pureFunctions = experimental("pureFunctions")
   val captureChecking = experimental("captureChecking")
   val into = experimental("into")
-  val namedTuples = experimental("namedTuples")
   val modularity = experimental("modularity")
   val betterMatchTypeExtractors = experimental("betterMatchTypeExtractors")
   val quotedPatternsWithPolymorphicFunctions = experimental("quotedPatternsWithPolymorphicFunctions")
@@ -64,7 +63,6 @@ object Feature:
     (pureFunctions, "Enable pure functions for capture checking"),
     (captureChecking, "Enable experimental capture checking"),
     (into, "Allow into modifier on parameter types"),
-    (namedTuples, "Allow named tuples"),
     (modularity, "Enable experimental modularity features"),
     (betterMatchTypeExtractors, "Enable better match type extractors"),
     (betterFors, "Enable improvements in `for` comprehensions")

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

@@ -671,7 +671,7 @@ object Parsers {
       else leading :: Nil
 
     def maybeNamed(op: () => Tree): () => Tree = () =>
-      if isIdent && in.lookahead.token == EQUALS && in.featureEnabled(Feature.namedTuples) then
+      if isIdent && in.lookahead.token == EQUALS && sourceVersion.enablesNamedTuples then
         atSpan(in.offset):
           val name = ident()
           in.nextToken()
@@ -1137,32 +1137,15 @@ object Parsers {
           if (prec < opPrec || leftAssoc && prec == opPrec) {
             opStack = opStack.tail
             recur {
-              migrateInfixOp(opInfo, isType):
-                atSpan(opInfo.operator.span union opInfo.operand.span union top.span):
-                  InfixOp(opInfo.operand, opInfo.operator, top)
+              atSpan(opInfo.operator.span union opInfo.operand.span union top.span):
+                InfixOp(opInfo.operand, opInfo.operator, top)
             }
           }
           else top
         }
       recur(top)
     }
 
-    private def migrateInfixOp(opInfo: OpInfo, isType: Boolean)(infixOp: InfixOp): Tree = {
-      def isNamedTupleOperator = opInfo.operator.name match
-        case nme.EQ | nme.NE |  nme.eq | nme.ne | nme.`++` | nme.zip => true
-        case _ => false
-      if isType then infixOp
-      else infixOp.right match
-        case Tuple(args) if args.exists(_.isInstanceOf[NamedArg]) && !isNamedTupleOperator =>
-          report.errorOrMigrationWarning(DeprecatedInfixNamedArgumentSyntax(), infixOp.right.srcPos, MigrationVersion.AmbiguousNamedTupleSyntax)
-          if MigrationVersion.AmbiguousNamedTupleSyntax.needsPatch then
-            val asApply = cpy.Apply(infixOp)(Select(opInfo.operand, opInfo.operator.name), args)
-            patch(source, infixOp.span, asApply.show(using ctx.withoutColors))
-            asApply // allow to use pre-3.6 syntax in migration mode
-          else infixOp
-        case _ => infixOp
-    }
-
     /** True if we are seeing a lambda argument after a colon of the form:
      *    : (params) =>
      *      body
@@ -2177,7 +2160,7 @@ object Parsers {
 
       if namedOK && isIdent && in.lookahead.token == EQUALS then
         commaSeparated(() => namedArgType())
-      else if tupleOK && isIdent && in.lookahead.isColon && in.featureEnabled(Feature.namedTuples) then
+      else if tupleOK && isIdent && in.lookahead.isColon && sourceVersion.enablesNamedTuples then
         commaSeparated(() => namedElem())
       else
         commaSeparated(() => argType())

compiler/src/dotty/tools/dotc/typer/Typer.scala

@@ -825,7 +825,7 @@ class Typer(@constructorOnly nestingLevel: Int = 0) extends Namer
     def tryNamedTupleSelection() =
       val namedTupleElems = qual.tpe.widenDealias.namedTupleElementTypes(true)
       val nameIdx = namedTupleElems.indexWhere(_._1 == selName)
-      if nameIdx >= 0 && Feature.enabled(Feature.namedTuples) then
+      if nameIdx >= 0 && sourceVersion.enablesNamedTuples then
         typed(
           untpd.Apply(
             untpd.Select(untpd.TypedSplice(qual), nme.apply),

compiler/test/dotty/tools/dotc/CompilationTests.scala

@@ -79,8 +79,6 @@ class CompilationTests {
       compileFile("tests/rewrites/i20002.scala", defaultOptions.and("-indent", "-rewrite")),
       compileDir("tests/rewrites/annotation-named-pararamters", defaultOptions.and("-rewrite", "-source:3.6-migration")),
       compileFile("tests/rewrites/i21418.scala", unindentOptions.and("-rewrite", "-source:3.5-migration")),
-      compileFile("tests/rewrites/infix-named-args.scala", defaultOptions.and("-rewrite", "-source:3.6-migration")),
-      compileFile("tests/rewrites/ambiguous-named-tuple-assignment.scala", defaultOptions.and("-rewrite", "-source:3.6-migration")),
       compileFile("tests/rewrites/i21382.scala", defaultOptions.and("-indent", "-rewrite")),
       compileFile("tests/rewrites/unused.scala", defaultOptions.and("-rewrite", "-Wunused:all")),
       compileFile("tests/rewrites/i22440.scala", defaultOptions.and("-rewrite"))

docs/_docs/reference/experimental/named-tuples.md renamed to docs/_docs/reference/other-new-features/named-tuples.md

@@ -1,10 +1,11 @@
 ---
 layout: doc-page
 title: "Named Tuples"
-nightlyOf: https://docs.scala-lang.org/scala3/reference/experimental/named-tuples.html
+nightlyOf: https://docs.scala-lang.org/scala3/reference/other-new-features/named-tuples.html
 ---
 
-The elements of a tuple can now be named. Example:
+Starting in Scala 3.7, the elements of a tuple can be named.
+Example:
 ```scala
 type Person = (name: String, age: Int)
 val Bob: Person = (name = "Bob", age = 33)

docs/sidebar.yml

@@ -72,6 +72,7 @@ subsection:
           - page: reference/other-new-features/export.md
           - page: reference/other-new-features/opaques.md
           - page: reference/other-new-features/opaques-details.md
+          - page: reference/other-new-features/named-tuples.md
           - page: reference/other-new-features/open-classes.md
           - page: reference/other-new-features/parameter-untupling.md
           - page: reference/other-new-features/parameter-untupling-spec.md
@@ -158,7 +159,6 @@ subsection:
           - page: reference/experimental/cc.md
           - page: reference/experimental/purefuns.md
           - page: reference/experimental/tupled-function.md
-          - page: reference/experimental/named-tuples.md
           - page: reference/experimental/modularity.md
           - page: reference/experimental/typeclasses.md
           - page: reference/experimental/runtimeChecked.md

language-server/test/dotty/tools/languageserver/CompletionTest.scala

@@ -1725,8 +1725,7 @@ class CompletionTest {
      .completion(m6, Set())
 
   @Test def namedTupleCompletion: Unit =
-    code"""|import scala.language.experimental.namedTuples
-           |
+    code"""|
            |val person: (name: String, city: String) =
            |  (name = "Jamie", city = "Lausanne")
            |

library/src/scala/NamedTuple.scala

@@ -1,8 +1,6 @@
 package scala
-import annotation.experimental
 import compiletime.ops.boolean.*
 
-@experimental
 object NamedTuple:
 
   /** The type to which named tuples get mapped to. For instance,
@@ -133,7 +131,6 @@ object NamedTuple:
 end NamedTuple
 
 /** Separate from NamedTuple object so that we can match on the opaque type NamedTuple. */
-@experimental
 object NamedTupleDecomposition:
   import NamedTuple.*
   extension [N <: Tuple, V <: Tuple](x: NamedTuple[N, V])

library/src/scala/runtime/stdLibPatches/language.scala

@@ -97,6 +97,7 @@ object language:
      *  @see [[https://dotty.epfl.ch/docs/reference/experimental/named-tuples]]
      */
     @compileTimeOnly("`namedTuples` can only be used at compile time in import statements")
+    @deprecated("The experimental.namedTuples language import is no longer needed since the feature is now standard", since = "3.7")
     object namedTuples
 
     /** Experimental support for new features for better modularity, including

presentation-compiler/test/dotty/tools/pc/tests/completion/CompletionSuite.scala

@@ -2032,8 +2032,7 @@ class CompletionSuite extends BaseCompletionSuite:
 
   @Test def `namedTuple completions` =
     check(
-      """|import scala.language.experimental.namedTuples
-         |import scala.NamedTuple.*
+      """|import scala.NamedTuple.*
          |
          |val person = (name = "Jamie", city = "Lausanne")
          |
@@ -2044,8 +2043,7 @@ class CompletionSuite extends BaseCompletionSuite:
 
   @Test def `Selectable with namedTuple Fields member` =
     check(
-      """|import scala.language.experimental.namedTuples
-         |import scala.NamedTuple.*
+      """|import scala.NamedTuple.*
          |
          |class NamedTupleSelectable extends Selectable {
          |  type Fields <: AnyNamedTuple