Macros are not experimental

Author: liufengyun

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

@@ -36,9 +36,9 @@ object Feature:
     Properties.experimental && !ctx.settings.YnoExperimental.value
 
   def isExperimental(feature: TermName): Boolean =
-    feature match
+    feature != scala2macros && feature.match
     case QualifiedName(nme.experimental, _) => true
-    case _ => true
+    case _ => false
 
   /** Is `feature` enabled by by a command-line setting? The enabling setting is
    *
@@ -117,7 +117,9 @@ object Feature:
   /** Check that experimental compiler options are only set for snapshot or nightly compiler versions. */
   def checkExperimentalFlags(using Context): Unit =
     if !experimentalEnabled then
-      val features = ctx.settings.language.value.filter(_.contains(nme.experimental.toString))
+      val features = ctx.settings.language.value.filter { feature =>
+        feature.contains(nme.experimental.toString) && !feature.contains("macros")
+      }
       if features.nonEmpty then
         report.error(
           experimentalWarningMessage +

compiler/src/dotty/tools/dotc/core/StdNames.scala

@@ -520,6 +520,7 @@ object StdNames {
     val longHash: N             = "longHash"
     val macroThis : N           = "_this"
     val macroContext : N        = "c"
+    val macros: N               = "macros"
     val main: N                 = "main"
     val manifest: N             = "manifest"
     val ManifestFactory: N      = "ManifestFactory"

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

@@ -3080,7 +3080,10 @@ object Parsers {
       val imp = Import(tree, selectors)
       if isLanguageImport(tree) then
         in.languageImportContext = in.languageImportContext.importContext(imp, NoSymbol)
-        if isExperimentalImport(tree) && !Feature.experimentalEnabled then
+        if isExperimentalImport(tree)
+           && !Feature.experimentalEnabled
+           && selectors.exists(_.name != nme.macros)
+        then
           report.error(Feature.experimentalWarningMessage, imp.srcPos)
         for
           case ImportSelector(id @ Ident(imported), EmptyTree, _) <- selectors