diff --git a/package-lock.json b/package-lock.json
index 2af5768..29a9d0a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -3562,6 +3562,12 @@
         }
       }
     },
+    "mock-fs": {
+      "version": "4.13.0",
+      "resolved": "https://registry.npmjs.org/mock-fs/-/mock-fs-4.13.0.tgz",
+      "integrity": "sha512-DD0vOdofJdoaRNtnWcrXe6RQbpHkPPmtqGq14uRX0F8ZKJ5nv89CVTYl/BZdppDxBDaV0hl75htg3abpEWlPZA==",
+      "dev": true
+    },
     "ms": {
       "version": "2.1.2",
       "resolved": "https://registry.npmjs.org/ms/-/ms-2.1.2.tgz",
diff --git a/package.json b/package.json
index 050c1a3..8248258 100644
--- a/package.json
+++ b/package.json
@@ -58,6 +58,7 @@
     "eslint-plugin-import": "^2.22.1",
     "eslint-plugin-mocha": "^8.0.0",
     "mocha": "^7.2.0",
+    "mock-fs": "^4.13.0",
     "nyc": "^15.1.0",
     "sinon": "^9.2.0"
   }