Add diagnostic for wrong specialize label

Author: kimdv

CodeGeneration/Sources/SyntaxSupport/AttributeNodes.swift

@@ -656,7 +656,15 @@ public let ATTRIBUTE_NODES: [Node] = [
     children: [
       Child(
         name: "Label",
-        kind: .node(kind: .token),
+        kind: .token(choices: [
+          .keyword(text: "target"),
+          .keyword(text: "availability"),
+          .keyword(text: "exported"),
+          .keyword(text: "kind"),
+          .keyword(text: "spi"),
+          .keyword(text: "spiModule"),
+          .keyword(text: "available"),
+        ]),
         nameForDiagnostics: "label",
         documentation: "The label of the argument"
       ),

Sources/SwiftParser/Attributes.swift

@@ -816,7 +816,8 @@ extension Parser {
         elements.append(
           .labeledSpecializeEntry(
             RawLabeledSpecializeEntrySyntax(
-              label: ident,
+              RawUnexpectedNodesSyntax([ident], arena: self.arena),
+              label: RawTokenSyntax(missing: .identifier, arena: self.arena),
               unexpectedBeforeColon,
               colon: colon,
               value: valueLabel,

Sources/SwiftParserDiagnostics/ParseDiagnosticsGenerator.swift

@@ -1120,6 +1120,33 @@ public class ParseDiagnosticsGenerator: SyntaxAnyVisitor {
     return .visitChildren
   }
 
+  public override func visit(_ node: LabeledSpecializeEntrySyntax) -> SyntaxVisitorContinueKind {
+    if shouldSkip(node) {
+      return .skipChildren
+    }
+
+    if let unexpectedIdentifier = node.unexpectedBeforeLabel?.onlyPresentToken(where: { $0.tokenKind.isIdentifier }) {
+      addDiagnostic(
+        unexpectedIdentifier,
+        UnknownParameterError(
+          parameter: unexpectedIdentifier,
+          validParameters: [
+            .keyword(.target),
+            .keyword(.availability),
+            .keyword(.exported),
+            .keyword(.kind),
+            .keyword(.spi),
+            .keyword(.spiModule),
+            .keyword(.available),
+          ]
+        ),
+        handledNodes: [unexpectedIdentifier.id, node.label.id]
+      )
+    }
+
+    return .visitChildren
+  }
+
   public override func visit(_ node: MacroExpansionDeclSyntax) -> SyntaxVisitorContinueKind {
     if shouldSkip(node) {
       return .skipChildren

Sources/SwiftParserDiagnostics/ParserDiagnosticMessages.swift

@@ -512,6 +512,23 @@ public struct UnknownDirectiveError: ParserError {
   }
 }
 
+public struct UnknownParameterError: ParserError {
+  public let parameter: TokenSyntax
+  public let validParameters: [TokenSyntax]
+
+  public var message: String {
+    var message = "unknown parameter '\(parameter.description)'"
+
+    if let parentTypeName = parameter.ancestorOrSelf(mapping: { $0.nodeTypeNameForDiagnostics(allowBlockNames: false) }) {
+      message += " in \(parentTypeName)"
+    }
+
+    message += "; valid parameters \(nodesDescription(validParameters, format: true))"
+
+    return message
+  }
+}
+
 // MARK: - Notes (please sort alphabetically)
 
 public struct EffectSpecifierDeclaredHere: ParserNote {

Sources/SwiftSyntax/generated/raw/RawSyntaxValidation.swift

@@ -1648,7 +1648,15 @@ func validateLayout(layout: RawSyntaxBuffer, as kind: SyntaxKind) {
   case .labeledSpecializeEntry:
     assert(layout.count == 9)
     assertNoError(kind, 0, verify(layout[0], as: RawUnexpectedNodesSyntax?.self))
-    assertNoError(kind, 1, verify(layout[1], as: RawTokenSyntax.self))
+    assertNoError(kind, 1, verify(layout[1], as: RawTokenSyntax.self, tokenChoices: [
+            .keyword("target"), 
+            .keyword("availability"), 
+            .keyword("exported"), 
+            .keyword("kind"), 
+            .keyword("spi"), 
+            .keyword("spiModule"), 
+            .keyword("available")
+          ]))
     assertNoError(kind, 2, verify(layout[2], as: RawUnexpectedNodesSyntax?.self))
     assertNoError(kind, 3, verify(layout[3], as: RawTokenSyntax.self, tokenChoices: [.tokenKind(.colon)]))
     assertNoError(kind, 4, verify(layout[4], as: RawUnexpectedNodesSyntax?.self))

Tests/SwiftParserTest/AttributeTests.swift

@@ -73,41 +73,64 @@ final class AttributeTests: XCTestCase {
   func testMissingClosingParenToAttribute() {
     assertParse(
       """
-      @_specializeℹ️(e1️⃣
+      @_specializeℹ️(1️⃣e2️⃣
       """,
       diagnostics: [
         DiagnosticSpec(
+          locationMarker: "1️⃣",
+          message: "unknown parameter 'e' in token; valid parameters 'target', 'availability', 'exported', 'kind', 'spi', 'spiModule', and 'available'"
+        ),
+        DiagnosticSpec(
+          locationMarker: "2️⃣",
           message: "expected ':' in attribute argument",
           fixIts: ["insert ':'"]
         ),
         DiagnosticSpec(
+          locationMarker: "2️⃣",
           message: "expected ')' to end attribute",
           notes: [NoteSpec(message: "to match this opening '('")],
           fixIts: ["insert ')'"]
         ),
         DiagnosticSpec(
+          locationMarker: "2️⃣",
           message: "expected declaration after attribute",
           fixIts: ["insert declaration"]
         ),
       ],
       fixedSource: """
-        @_specialize(e:) <#declaration#>
+        @_specialize(e  <#identifier#>:) <#declaration#>
         """
     )
   }
 
   func testMultipleInvalidSpecializeParams() {
     assertParse(
       """
-      @_specialize(e1️⃣, exported2️⃣)3️⃣
+      @_specialize(1️⃣e2️⃣, exported3️⃣)4️⃣
       """,
       diagnostics: [
-        DiagnosticSpec(locationMarker: "1️⃣", message: "expected ':' in attribute argument", fixIts: ["insert ':'"]),
-        DiagnosticSpec(locationMarker: "2️⃣", message: "expected ': false' in attribute argument", fixIts: ["insert ': false'"]),
-        DiagnosticSpec(locationMarker: "3️⃣", message: "expected declaration after attribute", fixIts: ["insert declaration"]),
+        DiagnosticSpec(
+          locationMarker: "1️⃣",
+          message: "unknown parameter 'e' in token; valid parameters 'target', 'availability', 'exported', 'kind', 'spi', 'spiModule', and 'available'"
+        ),
+        DiagnosticSpec(
+          locationMarker: "2️⃣",
+          message: "expected ':' in attribute argument",
+          fixIts: ["insert ':'"]
+        ),
+        DiagnosticSpec(
+          locationMarker: "3️⃣",
+          message: "expected ': false' in attribute argument",
+          fixIts: ["insert ': false'"]
+        ),
+        DiagnosticSpec(
+          locationMarker: "4️⃣",
+          message: "expected declaration after attribute",
+          fixIts: ["insert declaration"]
+        ),
       ],
       fixedSource: """
-        @_specialize(e:, exported: false)  <#declaration#>
+        @_specialize(e  <#identifier#>:, exported: false)  <#declaration#>
         """
     )
   }