this.classBackupDir = spec.getClassBackupDir();
        this.shouldBackupFiles = classBackupDir != null;
        this.result = result;
        this.uniqueIndex = new AtomicLong();
    }

    public void maybeBackupClassFile(String classFqName) {
        // Classes to compile are stashed before the compilation, so there is nothing to backup
        if (shouldBackupFiles && !classesToCompile.contains(classFqName)) {

            return DirectInstantiator.instantiate(incrementalCompileTaskClass, task,
                (Function<File, Optional<String>>) compilationSourceDirs::relativize,
                (Consumer<String>) classBackupService::maybeBackupClassFile,
                (Consumer<Map<String, Set<String>>>) sourceToClassMapping::putAll,
                (BiConsumer<String, String>) constantsAnalysisResult::addPublicDependent,

            result.getSourceClassesMapping().computeIfAbsent(relativePath, key -> new HashSet<>()).add(classFqName);
            compilationClassBackupService.maybeBackupClassFile(classFqName);
            Iterator<InnerClassNode> iterator = classNode.getInnerClasses();
            while (iterator.hasNext()) {
                inspectClassNode(sourceUnit, iterator.next());
            }