diff --git a/package.json b/package.json
index 621f989..e7c18d4 100644
--- a/package.json
+++ b/package.json
@@ -83,7 +83,7 @@
     "babel-plugin-transform-remove-console": "6.9.4",
     "babel-plugin-unassert": "3.2.0",
     "babel-preset-power-assert": "3.0.0",
-    "c8": "8.0.0",
+    "c8": "8.0.1",
     "esdoc": "1.1.0",
     "esdoc-ecmascript-proposal-plugin": "1.0.0",
     "esdoc-inject-script-plugin": "1.0.0",
diff --git a/yarn.lock b/yarn.lock
index 4e4f0fc..8cfa379 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3478,23 +3478,23 @@ bundle-name@^3.0.0:
   dependencies:
     run-applescript "^5.0.0"
 
-c8@8.0.0:
-  version "8.0.0"
-  resolved "https://registry.yarnpkg.com/c8/-/c8-8.0.0.tgz#99c7408fbbafaa5630ddc80881adbfe461fc6c8f"
-  integrity sha512-XHA5vSfCLglAc0Xt8eLBZMv19lgiBSjnb1FLAQgnwkuhJYEonpilhEB4Ea3jPAbm0FhD6VVJrc0z73jPe7JyGQ==
+c8@8.0.1:
+  version "8.0.1"
+  resolved "https://registry.yarnpkg.com/c8/-/c8-8.0.1.tgz#bafd60be680e66c5530ee69f621e45b1364af9fd"
+  integrity sha512-EINpopxZNH1mETuI0DzRA4MZpAUH+IFiRhnmFD3vFr3vdrgxqi3VfE3KL0AIL+zDq8rC9bZqwM/VDmmoe04y7w==
   dependencies:
     "@bcoe/v8-coverage" "^0.2.3"
     "@istanbuljs/schema" "^0.1.3"
     find-up "^5.0.0"
     foreground-child "^2.0.0"
     istanbul-lib-coverage "^3.2.0"
-    istanbul-lib-report "^3.0.0"
-    istanbul-reports "^3.1.4"
+    istanbul-lib-report "^3.0.1"
+    istanbul-reports "^3.1.6"
     rimraf "^3.0.2"
     test-exclude "^6.0.0"
     v8-to-istanbul "^9.0.0"
-    yargs "^16.2.0"
-    yargs-parser "^20.2.9"
+    yargs "^17.7.2"
+    yargs-parser "^21.1.1"
 
 cacheable-lookup@^5.0.3:
   version "5.0.4"
@@ -6876,10 +6876,19 @@ istanbul-lib-report@^3.0.0:
     make-dir "^3.0.0"
     supports-color "^7.1.0"
 
-istanbul-reports@^3.1.4:
-  version "3.1.4"
-  resolved "https://registry.yarnpkg.com/istanbul-reports/-/istanbul-reports-3.1.4.tgz#1b6f068ecbc6c331040aab5741991273e609e40c"
-  integrity sha512-r1/DshN4KSE7xWEknZLLLLDn5CJybV3nw01VTkp6D5jzLuELlcbudfj/eSQFvrKsJuTVCGnePO7ho82Nw9zzfw==
+istanbul-lib-report@^3.0.1:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/istanbul-lib-report/-/istanbul-lib-report-3.0.1.tgz#908305bac9a5bd175ac6a74489eafd0fc2445a7d"
+  integrity sha512-GCfE1mtsHGOELCU8e/Z7YWzpmybrx/+dSTfLrvY8qRmaY6zXTKWn6WQIjaAFw069icm6GVMNkgu0NzI4iPZUNw==
+  dependencies:
+    istanbul-lib-coverage "^3.0.0"
+    make-dir "^4.0.0"
+    supports-color "^7.1.0"
+
+istanbul-reports@^3.1.6:
+  version "3.1.6"
+  resolved "https://registry.yarnpkg.com/istanbul-reports/-/istanbul-reports-3.1.6.tgz#2544bcab4768154281a2f0870471902704ccaa1a"
+  integrity sha512-TLgnMkKg3iTDsQ9PbPTdpfAK2DzjF9mqUG7RMgcQl8oFjad8ob4laGxv5XV5U9MAfx8D6tSJiUyuAwzLicaxlg==
   dependencies:
     html-escaper "^2.0.0"
     istanbul-lib-report "^3.0.0"
@@ -7542,6 +7551,13 @@ make-dir@^3.0.0, make-dir@^3.0.2:
   dependencies:
     semver "^6.0.0"
 
+make-dir@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/make-dir/-/make-dir-4.0.0.tgz#c3c2307a771277cd9638305f915c29ae741b614e"
+  integrity sha512-hXdUTZYIVOt1Ex//jAQi+wTZZpUpwBj/0QsOzqegb3rGMMeJiSEu5xLHnYfBrRV4RH2+OCSOO95Is/7x1WJ4bw==
+  dependencies:
+    semver "^7.5.3"
+
 make-error@^1.1.1:
   version "1.3.6"
   resolved "https://registry.yarnpkg.com/make-error/-/make-error-1.3.6.tgz#2eb2e37ea9b67c4891f684a1394799af484cf7a2"
@@ -9766,6 +9782,13 @@ semver@^7.5.1:
   dependencies:
     lru-cache "^6.0.0"
 
+semver@^7.5.3:
+  version "7.5.4"
+  resolved "https://registry.yarnpkg.com/semver/-/semver-7.5.4.tgz#483986ec4ed38e1c6c48c34894a9182dbff68a6e"
+  integrity sha512-1bCSESV6Pv+i21Hvpxp3Dx+pSD8lIPt8uVjRrxAUt/nbswYc+tK6Y2btiULjd4+fnq15PX+nqQDC7Oft7WkwcA==
+  dependencies:
+    lru-cache "^6.0.0"
+
 serialize-error@^7.0.1:
   version "7.0.1"
   resolved "https://registry.yarnpkg.com/serialize-error/-/serialize-error-7.0.1.tgz#f1360b0447f61ffb483ec4157c737fab7d778e18"
@@ -10984,7 +11007,7 @@ yaml@^2.2.2:
   resolved "https://registry.yarnpkg.com/yaml/-/yaml-2.2.2.tgz#ec551ef37326e6d42872dad1970300f8eb83a073"
   integrity sha512-CBKFWExMn46Foo4cldiChEzn7S7SRV+wqiluAb6xmueD/fGyRHIhX8m14vVGgeFWjN540nKCNVj6P21eQjgTuA==
 
-yargs-parser@^20.2.2, yargs-parser@^20.2.3, yargs-parser@^20.2.9:
+yargs-parser@^20.2.3:
   version "20.2.9"
   resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-20.2.9.tgz#2eb7dc3b0289718fc295f362753845c41a0c94ee"
   integrity sha512-y11nGElTIV+CT3Zv9t7VKl+Q3hTQoT9a1Qzezhhl6Rp21gJ/IVTW7Z3y9EWXhuUBC2Shnf+DX0antecpAwSP8w==
@@ -10999,19 +11022,6 @@ yargs-parser@^21.1.1:
   resolved "https://registry.yarnpkg.com/yargs-parser/-/yargs-parser-21.1.1.tgz#9096bceebf990d21bb31fa9516e0ede294a77d35"
   integrity sha512-tVpsJW7DdjecAiFpbIB1e3qxIQsE6NoPc5/eTdrbbIC4h0LVsWhnoa3g+m2HclBIujHzsxZ4VJVA+GUuc2/LBw==
 
-yargs@^16.2.0:
-  version "16.2.0"
-  resolved "https://registry.yarnpkg.com/yargs/-/yargs-16.2.0.tgz#1c82bf0f6b6a66eafce7ef30e376f49a12477f66"
-  integrity sha512-D1mvvtDG0L5ft/jGWkLpG1+m0eQxOfaBvTNELraWj22wSVUMWxZUvYgJYcKh6jGGIkJFhH4IZPQhR4TKpc8mBw==
-  dependencies:
-    cliui "^7.0.2"
-    escalade "^3.1.1"
-    get-caller-file "^2.0.5"
-    require-directory "^2.1.1"
-    string-width "^4.2.0"
-    y18n "^5.0.5"
-    yargs-parser "^20.2.2"
-
 yargs@^17.0.0:
   version "17.3.0"
   resolved "https://registry.yarnpkg.com/yargs/-/yargs-17.3.0.tgz#295c4ffd0eef148ef3e48f7a2e0f58d0e4f26b1c"