for (cacheDir in dir.asFile.listFiles()) {
            if (!cacheDir.name.matches(dirVersionPattern)) {
                continue
            }
            for (name in listOf("fileHashes", "outputFileStates", "fileSnapshots")) {
                val stateDir = File(cacheDir, name)
                if (stateDir.isDirectory) {
                    logger.lifecycle("Removing old cache directory : $stateDir")