 
     internal var syntaxMap: SyntaxMap {
         guard let syntaxMap = syntaxMapCache.get(self) else {
+            if let handler = assertHandler {
+                handler()
+                return SyntaxMap(data: [])
+            }
             fatalError("Never call this for file that sourcekitd fails.")
         }
         return syntaxMap

        }
    }

    internal var structure: Structure {
        guard let structure = structureCache.get(self) else {
            fatalError("Never call this for file that sourcekitd fails.")
        }
        return structure


    internal var syntaxKindsByLines: [[SyntaxKind]] {
        guard let syntaxKindsByLines = syntaxKindsByLinesCache.get(self) else {
            if let handler = assertHandler {
                handler()
                return []
            }
            fatalError("Never call this for file that sourcekitd fails.")
        }
        return syntaxKindsByLines
