Print children for "Could not find subtree after UTF8 offset" syntax comparison error message

Author: ahoppen

Sources/_SwiftSyntaxTestSupport/Syntax+Assertions.swift

@@ -186,7 +186,7 @@ public enum SubtreeError: Error, CustomStringConvertible {
     case let .invalidMarker(name):
       return "Could not find marker with name '\(name)'"
     case let .invalidSubtree(tree, afterUTF8Offset, type):
-      return "Could not find subtree after UTF8 offset \(afterUTF8Offset) with type \(type) in:\n\(tree.debugDescription)"
+      return "Could not find subtree after UTF8 offset \(afterUTF8Offset) with type \(type) in:\n\(tree.debugDescription(includeChildren: true))"
     }
   }
 }