[sending] Add support for 'sending'.

rdar://128216574

Author: gottesmm

CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift

@@ -472,6 +472,7 @@ public let DECL_NODES: [Node] = [
           .keyword(.transferring),
           .keyword(.unowned),
           .keyword(.weak),
+          .keyword(.sending),
         ])
       ),
       Child(

CodeGeneration/Sources/SyntaxSupport/ExperimentalFeatures.swift

@@ -19,6 +19,7 @@ public enum ExperimentalFeature: String, CaseIterable {
   case nonescapableTypes
   case transferringArgsAndResults
   case trailingComma
+  case sendingArgsAndResults
 
   /// The name of the feature, which is used in the doc comment.
   public var featureName: String {
@@ -35,6 +36,8 @@ public enum ExperimentalFeature: String, CaseIterable {
       return "TransferringArgsAndResults"
     case .trailingComma:
       return "trailing comma"
+    case .sendingArgsAndResults:
+      return "SendingArgsAndResults"
     }
   }
 

CodeGeneration/Sources/SyntaxSupport/KeywordSpec.swift

@@ -263,6 +263,7 @@ public enum Keyword: CaseIterable {
   case safe
   case scoped
   case `self`
+  case sending
   case `Self`
   case Sendable
   case set
@@ -701,6 +702,11 @@ public enum Keyword: CaseIterable {
         "transferring",
         experimentalFeature: .transferringArgsAndResults
       )
+    case .sending:
+      return KeywordSpec(
+        "sending",
+        experimentalFeature: .sendingArgsAndResults
+      )
     case .transpose:
       return KeywordSpec("transpose")
     case .true:

CodeGeneration/Sources/SyntaxSupport/TypeNodes.swift

@@ -593,6 +593,7 @@ public let TYPE_NODES: [Node] = [
           .keyword(.consuming),
           .keyword(.transferring),
           .keyword(._resultDependsOn),
+          .keyword(.sending),
         ]),
         documentation: "The specifier token that's attached to the type."
       )

Sources/SwiftParser/Declarations.swift

@@ -23,7 +23,7 @@ extension DeclarationModifier {
       .borrowing, .class, .consuming, .convenience, .distributed, .dynamic,
       .final, .indirect, .infix, .isolated, .lazy, .mutating, .nonmutating,
       .optional, .override, .postfix, .prefix, .reasync, ._resultDependsOn, ._resultDependsOnSelf, .required,
-      .rethrows, .static, .weak, .transferring:
+      .rethrows, .static, .weak, .transferring, .sending:
       return false
     case .fileprivate, .internal, .nonisolated, .package, .open, .private,
       .public, .unowned:

Sources/SwiftParser/Patterns.swift

@@ -378,6 +378,7 @@ extension Parser.Lookahead {
         && !self.at(.keyword(.borrowing))
         && !self.at(.keyword(.consuming))
         && !(experimentalFeatures.contains(.transferringArgsAndResults) && self.at(.keyword(.transferring)))
+        && !(experimentalFeatures.contains(.sendingArgsAndResults) && self.at(.keyword(.sending)))
         && !(experimentalFeatures.contains(.nonescapableTypes) && self.at(.keyword(._resultDependsOn)))
       {
         return true

Sources/SwiftParser/TokenPrecedence.swift

@@ -237,7 +237,7 @@ enum TokenPrecedence: Comparable {
       .__setter_access, .indirect, .isolated, .nonisolated, .distributed, ._local,
       .inout, ._mutating, ._borrow, ._borrowing, .borrowing, ._consuming, .consuming, .consume, ._resultDependsOnSelf,
       ._resultDependsOn,
-      .transferring, .dependsOn, .scoped,
+      .transferring, .dependsOn, .scoped, .sending,
       // Accessors
       .get, .set, .didSet, .willSet, .unsafeAddress, .addressWithOwner, .addressWithNativeOwner, .unsafeMutableAddress,
       .mutableAddressWithOwner, .mutableAddressWithNativeOwner, ._read, ._modify,

Sources/SwiftParser/TokenSpecSet.swift

@@ -377,6 +377,7 @@ enum DeclarationModifier: TokenSpecSet {
   case reasync
   case required
   case `rethrows`
+  case sending
   case `static`
   case transferring
   case unowned
@@ -420,6 +421,7 @@ enum DeclarationModifier: TokenSpecSet {
     case TokenSpec(.rethrows): self = .rethrows
     case TokenSpec(.static): self = .static
     case TokenSpec(.transferring): self = .transferring
+    case TokenSpec(.sending): self = .sending
     case TokenSpec(.unowned): self = .unowned
     case TokenSpec(.weak): self = .weak
     case TokenSpec(._resultDependsOn) where experimentalFeatures.contains(.nonescapableTypes): self = ._resultDependsOn
@@ -465,6 +467,7 @@ enum DeclarationModifier: TokenSpecSet {
     case .rethrows: return TokenSpec(.rethrows, recoveryPrecedence: .declKeyword)
     case .static: return .keyword(.static)
     case .transferring: return .keyword(.transferring)
+    case .sending: return .keyword(.sending)
     case .unowned: return TokenSpec(.unowned, recoveryPrecedence: .declKeyword)
     case .weak: return TokenSpec(.weak, recoveryPrecedence: .declKeyword)
     case ._resultDependsOn: return TokenSpec(._resultDependsOn, recoveryPrecedence: .declKeyword)

Tests/SwiftParserTest/DeclarationTests.swift

@@ -3309,6 +3309,21 @@ final class DeclarationTests: ParserTestCase {
     )
   }
 
+  func testSendingTypeSpecifier() {
+    assertParse(
+      "func testVarDeclTupleElt() -> (sending String, String) {}",
+      experimentalFeatures: .sendingArgsAndResults
+    )
+    assertParse(
+      "func testVarDeclTuple2(_ x: (sending String)) {}",
+      experimentalFeatures: .sendingArgsAndResults
+    )
+    assertParse(
+      "func testVarDeclTuple2(_ x: (sending String, String)) {}",
+      experimentalFeatures: .sendingArgsAndResults
+    )
+  }
+
   func testMisplacedAttributeInVarDeclWithMultipleBindings() {
     assertParse(
       """