When formatting, insert a trailing space after 'async'

Author: ahoppen

CodeGeneration/Sources/generate-swiftbasicformat/BasicFormatFile.swift

@@ -168,7 +168,7 @@ private func createTokenFormatFunction() -> FunctionDecl {
   ) {
     VariableDecl("var node = node")
     SwitchStmt(expression: MemberAccessExpr(base: "node", name: "tokenKind")) {
-      for token in SYNTAX_TOKENS {
+      for token in SYNTAX_TOKENS where token.name != "ContextualKeyword" {
         SwitchCase(label: SwitchCaseLabel(caseItems: CaseItem(pattern: ExpressionPattern(expression: MemberAccessExpr(name: token.swiftKind))))) {
           if token.requiresLeadingSpace {
             IfStmt(
@@ -196,6 +196,20 @@ private func createTokenFormatFunction() -> FunctionDecl {
       SwitchCase(label: SwitchCaseLabel(caseItems: CaseItem(pattern: ExpressionPattern(expression: MemberAccessExpr(name: "eof"))))) {
         BreakStmt("break")
       }
+      SwitchCase(label: SwitchCaseLabel(caseItems: CaseItem(pattern: ExpressionPattern(expression: MemberAccessExpr(name: "contextualKeyword"))))) {
+        SwitchStmt(
+          """
+          switch node.text {
+            case "async":
+              if node.trailingTrivia.isEmpty {
+                node.trailingTrivia += .space
+              }
+            default:
+              break
+          }
+          """
+        )
+      }
     }
     SequenceExpr("node.leadingTrivia = node.leadingTrivia.indented(indentation: indentation)")
     SequenceExpr("node.trailingTrivia = node.trailingTrivia.indented(indentation: indentation)")

Sources/SwiftBasicFormat/generated/BasicFormat.swift

@@ -3147,8 +3147,6 @@ open class BasicFormat: SyntaxRewriter {
       break
     case .dollarIdentifier: 
       break
-    case .contextualKeyword: 
-      break
     case .rawStringDelimiter: 
       break
     case .stringSegment: 
@@ -3159,6 +3157,15 @@ open class BasicFormat: SyntaxRewriter {
       break
     case .eof: 
       break
+    case .contextualKeyword: 
+      switch node.text {
+        case "async":
+          if node.trailingTrivia.isEmpty {
+            node.trailingTrivia += .space
+          }
+        default:
+          break
+      }
     }
     node.leadingTrivia = node.leadingTrivia.indented(indentation: indentation)
     node.trailingTrivia = node.trailingTrivia.indented(indentation: indentation)