 
     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

})
private var syntaxMapCache = Cache({file in responseCache.get(file).map(SyntaxMap.init)})
private var syntaxKindsByLinesCache = Cache({file in file.syntaxKindsByLine()})

private var _allDeclarationsByType = [String: [String]]()
private var queueForRebuild = [Structure]()


    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
