Merge pull request #1033 from ahoppen/ahoppen/separate-non-punctuation

Make sure that any keyword or identifier inserted by a Fix-It is separated from the previous one by trivia

Author: ahoppen

Sources/SwiftParserDiagnostics/DiagnosticExtensions.swift

@@ -11,6 +11,7 @@
 //===----------------------------------------------------------------------===//
 
 import SwiftDiagnostics
+import SwiftBasicFormat
 import SwiftSyntax
 
 extension FixIt {
@@ -91,6 +92,18 @@ extension FixIt.Changes {
         ),
         .replaceLeadingTrivia(token: nextToken, newTrivia: [])
       ]
+    } else if let firstToken = node.firstToken(viewMode: .all),
+              let previousToken = node.previousToken(viewMode: .fixedUp),
+              !firstToken.tokenKind.isPunctuation,
+              !previousToken.tokenKind.isPunctuation,
+              firstToken.leadingTrivia.isEmpty,
+              (previousToken.presence == .missing ? BasicFormat().visit(previousToken).trailingTrivia : previousToken.trailingTrivia).isEmpty {
+      /// If neither this nor the previous token are punctionation make sure they
+      /// are separated by a space.
+      return [.replace(
+        oldNode: Syntax(node),
+        newNode: Syntax(presentNode).withLeadingTrivia(.space)
+      )]
     } else {
       return [.replace(
         oldNode: Syntax(node),

Tests/SwiftParserTest/translated/ToplevelLibraryTests.swift

@@ -44,7 +44,9 @@ final class ToplevelLibraryTests: XCTestCase {
       """,
       diagnostics: [
         DiagnosticSpec(message: "expected 'in', expression, and body in 'for' statement"),
-      ]
+      ], fixedSource: """
+        for i in <#expression#> {}
+        """
     )
   }
 }