Specify node names for diagnostics in gyb_syntax_support

Sources/SwiftParser/Diagnostics/ParserDiagnosticMessages.swift

@@ -16,25 +16,14 @@ import SwiftSyntax
 let diagnosticDomain: String = "SwiftParser"
 
 extension Syntax {
-  // FIXME: These should be defined in gyb_syntax_support.
   var nodeTypeNameForDiagnostics: String? {
-    if self.is(DeclSyntax.self) {
-      return "declaration"
-    } else if self.is(ExprSyntax.self) {
-      return "expression"
-    } else if self.is(PatternSyntax.self) {
-      return "pattern"
-    } else if self.is(StmtSyntax.self) {
-      return "statement"
-    } else if self.is(TypeSyntax.self) {
-      return "type"
-    } else if self.is(FunctionParameterSyntax.self) {
-      return "function parameter"
-    } else if self.is(ParameterClauseSyntax.self) {
-      return "parameter clause"
-    } else {
-      return nil
+    if let name = self.as(SyntaxEnum.self).nameForDiagnostics {
+      return name
+    }
+    if let parent = self.parent {
+      return parent.nodeTypeNameForDiagnostics
     }
+    return nil
   }
 }
 

Sources/SwiftSyntax/SyntaxEnum.swift.gyb

@@ -30,6 +30,23 @@ public enum SyntaxEnum {
   case ${node.swift_syntax_kind}(${node.name})
 %   end
 % end
+
+  public var nameForDiagnostics: String? {
+    switch self {
+    case .unknown:
+      return nil
+    case .token:
+      return "token"
+% for node in NON_BASE_SYNTAX_NODES:
+    case .${node.swift_syntax_kind}:
+%   if node.name_for_diagnostics:
+      return "${node.name_for_diagnostics}"
+%   else:
+      return nil
+%   end
+% end
+    }
+  }
 }
 
 public extension Syntax {