chore: dependency vendoring of markdownlint-rule-helpers

.eslintrc.json

@@ -1,7 +1,11 @@
 {
   "extends": ["conventions", "prettier"],
-  "plugins": ["prettier"],
+  "plugins": ["prettier", "import", "unicorn"],
+  "parserOptions": {
+    "project": "./tsconfig.json"
+  },
   "rules": {
-    "prettier/prettier": "error"
+    "prettier/prettier": "error",
+    "import/extensions": ["error", "always"]
   }
 }

jsconfig.json

@@ -9,6 +9,7 @@
     "noEmit": true,
     "rootDir": ".",
     "baseUrl": ".",
+    "skipLibCheck": true,
     "strict": true,
     "allowUnusedLabels": false,
     "allowUnreachableCode": false,
@@ -19,8 +20,6 @@
     "noUncheckedIndexedAccess": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
-    "forceConsistentCasingInFileNames": true,
+    "forceConsistentCasingInFileNames": true
-    "maxNodeModuleJsDepth": 0
+  }
-  },
-  "exclude": ["node_modules"]
 }

package-lock.json

@@ -10,27 +10,25 @@
       "hasInstallScript": true,
       "license": "MIT",
       "dependencies": {
-        "markdown-it": "14.0.0",
+        "markdown-it": "14.0.0"
-        "markdownlint-rule-helpers": "0.24.0"
       },
       "devDependencies": {
         "@commitlint/cli": "18.4.4",
         "@commitlint/config-conventional": "18.4.4",
         "@types/markdown-it": "13.0.7",
-        "@types/node": "20.10.8",
+        "@types/node": "20.11.0",
         "editorconfig-checker": "5.1.2",
         "eslint": "8.56.0",
         "eslint-config-conventions": "13.1.0",
         "eslint-config-prettier": "9.1.0",
         "eslint-plugin-import": "2.29.1",
-        "eslint-plugin-prettier": "5.1.2",
+        "eslint-plugin-prettier": "5.1.3",
         "eslint-plugin-promise": "6.1.1",
         "eslint-plugin-unicorn": "50.0.1",
         "husky": "8.0.3",
         "lint-staged": "15.2.0",
         "markdownlint": "0.33.0",
         "markdownlint-cli2": "0.11.0",
-        "markdownlint-rule-helpers": "0.24.0",
         "pinst": "3.0.0",
         "prettier": "3.1.1",
         "semantic-release": "22.0.12",
@@ -559,13 +557,13 @@
       }
     },
     "node_modules/@humanwhocodes/config-array": {
-      "version": "0.11.13",
+      "version": "0.11.14",
-      "resolved": "https://registry.npmjs.org/@humanwhocodes/config-array/-/config-array-0.11.13.tgz",
+      "resolved": "https://registry.npmjs.org/@humanwhocodes/config-array/-/config-array-0.11.14.tgz",
-      "integrity": "sha512-JSBDMiDKSzQVngfRjOdFXgFfklaXI4K9nLF49Auh21lmBWRLIK3+xTErTWD4KU54pb6coM6ESE7Awz/FNU3zgQ==",
+      "integrity": "sha512-3T8LkOmg45BV5FICb15QQMsyUSWrQ8AygVfC7ZG32zOalnqrilm018ZVCw0eapXux8FtA33q8PSRSstjee3jSg==",
       "dev": true,
       "dependencies": {
-        "@humanwhocodes/object-schema": "^2.0.1",
+        "@humanwhocodes/object-schema": "^2.0.2",
-        "debug": "^4.1.1",
+        "debug": "^4.3.1",
         "minimatch": "^3.0.5"
       },
       "engines": {
@@ -586,9 +584,9 @@
       }
     },
     "node_modules/@humanwhocodes/object-schema": {
-      "version": "2.0.1",
+      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/@humanwhocodes/object-schema/-/object-schema-2.0.1.tgz",
+      "resolved": "https://registry.npmjs.org/@humanwhocodes/object-schema/-/object-schema-2.0.2.tgz",
-      "integrity": "sha512-dvuCeX5fC9dXgJn9t+X5atfmgQAzUOWqS1254Gh0m6i8wKd10ebXkfNKiRK+1GWi/yTvvLDHpoxLr0xxxeslWw==",
+      "integrity": "sha512-6EwiSjwWYP7pTckG6I5eyFANjPhmPjUX9JRLUSfNPC7FX7zK9gyZAfUEaECL6ALTpGX5AjnBq3C9XmVWPitNpw==",
       "dev": true
     },
     "node_modules/@nodelib/fs.scandir": {
@@ -1327,9 +1325,9 @@
       "dev": true
     },
     "node_modules/@types/node": {
-      "version": "20.10.8",
+      "version": "20.11.0",
-      "resolved": "https://registry.npmjs.org/@types/node/-/node-20.10.8.tgz",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-20.11.0.tgz",
-      "integrity": "sha512-f8nQs3cLxbAFc00vEU59yf9UyGUftkPaLGfvbVOIDdx2i1b8epBqj2aNGyP19fiyXWvlmZ7qC1XLjAzw/OKIeA==",
+      "integrity": "sha512-o9bjXmDNcF7GbM4CNQpmi+TutCgap/K3w1JyKgxAjqx41zp9qlIAVFi0IhCNsJcXolEqLWhbFbEeL0PvYm4pcQ==",
       "dev": true,
       "dependencies": {
         "undici-types": "~5.26.4"
@@ -2424,9 +2422,9 @@
       }
     },
     "node_modules/electron-to-chromium": {
-      "version": "1.4.625",
+      "version": "1.4.628",
-      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.4.625.tgz",
+      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.4.628.tgz",
-      "integrity": "sha512-DENMhh3MFgaPDoXWrVIqSPInQoLImywfCwrSmVl3cf9QHzoZSiutHwGaB/Ql3VkqcQV30rzgdM+BjKqBAJxo5Q==",
+      "integrity": "sha512-2k7t5PHvLsufpP6Zwk0nof62yLOsCf032wZx7/q0mv8gwlXjhcxI3lz6f0jBr0GrnWKcm3burXzI3t5IrcdUxw==",
       "dev": true
     },
     "node_modules/emoji-regex": {
@@ -2913,9 +2911,9 @@
       }
     },
     "node_modules/eslint-plugin-prettier": {
-      "version": "5.1.2",
+      "version": "5.1.3",
-      "resolved": "https://registry.npmjs.org/eslint-plugin-prettier/-/eslint-plugin-prettier-5.1.2.tgz",
+      "resolved": "https://registry.npmjs.org/eslint-plugin-prettier/-/eslint-plugin-prettier-5.1.3.tgz",
-      "integrity": "sha512-dhlpWc9vOwohcWmClFcA+HjlvUpuyynYs0Rf+L/P6/0iQE6vlHW9l5bkfzN62/Stm9fbq8ku46qzde76T1xlSg==",
+      "integrity": "sha512-C9GCVAs4Eq7ZC/XFQHITLiHJxQngdtraXaM+LoUFoFp/lHNl2Zn8f3WQbe9HvTBBQ9YnKFB0/2Ajdqwo5D1EAw==",
       "dev": true,
       "dependencies": {
         "prettier-linter-helpers": "^1.0.0",
@@ -5176,30 +5174,6 @@
         "url": "https://github.com/sponsors/DavidAnson"
       }
     },
-    "node_modules/markdownlint-rule-helpers": {
-      "version": "0.24.0",
-      "resolved": "https://registry.npmjs.org/markdownlint-rule-helpers/-/markdownlint-rule-helpers-0.24.0.tgz",
-      "integrity": "sha512-Q7l/VO0ro3+oK7ZzB0aODVFwD0/X+S3JXM9ItdTTgo23yqsv7XzGHx+cGp/zlqD1W8+uiSoXflMVXzh5KSKskA==",
-      "dev": true,
-      "dependencies": {
-        "markdownlint-micromark": "0.1.2"
-      },
-      "engines": {
-        "node": ">=16"
-      },
-      "funding": {
-        "url": "https://github.com/sponsors/DavidAnson"
-      }
-    },
-    "node_modules/markdownlint-rule-helpers/node_modules/markdownlint-micromark": {
-      "version": "0.1.2",
-      "resolved": "https://registry.npmjs.org/markdownlint-micromark/-/markdownlint-micromark-0.1.2.tgz",
-      "integrity": "sha512-jRxlQg8KpOfM2IbCL9RXM8ZiYWz2rv6DlZAnGv8ASJQpUh6byTBnEsbuMZ6T2/uIgntyf7SKg/mEaEBo1164fQ==",
-      "dev": true,
-      "engines": {
-        "node": ">=14.18.0"
-      }
-    },
     "node_modules/marked": {
       "version": "9.1.6",
       "resolved": "https://registry.npmjs.org/marked/-/marked-9.1.6.tgz",
@@ -5436,9 +5410,9 @@
       }
     },
     "node_modules/npm": {
-      "version": "10.2.5",
+      "version": "10.3.0",
-      "resolved": "https://registry.npmjs.org/npm/-/npm-10.2.5.tgz",
+      "resolved": "https://registry.npmjs.org/npm/-/npm-10.3.0.tgz",
-      "integrity": "sha512-lXdZ7titEN8CH5YJk9C/aYRU9JeDxQ4d8rwIIDsvH3SMjLjHTukB2CFstMiB30zXs4vCrPN2WH6cDq1yHBeJAw==",
+      "integrity": "sha512-9u5GFc1UqI2DLlGI7QdjkpIaBs3UhTtY8KoCqYJK24gV/j/tByaI4BA4R7RkOc+ASqZMzFPKt4Pj2Z8JcGo//A==",
       "bundleDependencies": [
         "@isaacs/string-locale-compare",
         "@npmcli/arborist",
@@ -5520,12 +5494,12 @@
         "@npmcli/fs": "^3.1.0",
         "@npmcli/map-workspaces": "^3.0.4",
         "@npmcli/package-json": "^5.0.0",
-        "@npmcli/promise-spawn": "^7.0.0",
+        "@npmcli/promise-spawn": "^7.0.1",
-        "@npmcli/run-script": "^7.0.2",
+        "@npmcli/run-script": "^7.0.3",
         "@sigstore/tuf": "^2.2.0",
         "abbrev": "^2.0.0",
         "archy": "~1.0.0",
-        "cacache": "^18.0.1",
+        "cacache": "^18.0.2",
         "chalk": "^5.3.0",
         "ci-info": "^4.0.0",
         "cli-columns": "^4.0.0",
@@ -5679,7 +5653,7 @@
       }
     },
     "node_modules/npm/node_modules/@npmcli/arborist": {
-      "version": "7.2.2",
+      "version": "7.3.0",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -5726,7 +5700,7 @@
       }
     },
     "node_modules/npm/node_modules/@npmcli/config": {
-      "version": "8.0.3",
+      "version": "8.1.0",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -5784,7 +5758,7 @@
       }
     },
     "node_modules/npm/node_modules/@npmcli/git": {
-      "version": "5.0.3",
+      "version": "5.0.4",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -5885,7 +5859,7 @@
       }
     },
     "node_modules/npm/node_modules/@npmcli/promise-spawn": {
-      "version": "7.0.0",
+      "version": "7.0.1",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -5909,7 +5883,7 @@
       }
     },
     "node_modules/npm/node_modules/@npmcli/run-script": {
-      "version": "7.0.2",
+      "version": "7.0.3",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -6013,18 +5987,6 @@
         "node": "^14.17.0 || ^16.13.0 || >=18.0.0"
       }
     },
-    "node_modules/npm/node_modules/abort-controller": {
-      "version": "3.0.0",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT",
-      "dependencies": {
-        "event-target-shim": "^5.0.0"
-      },
-      "engines": {
-        "node": ">=6.5"
-      }
-    },
     "node_modules/npm/node_modules/agent-base": {
       "version": "7.1.0",
       "dev": true,
@@ -6087,14 +6049,10 @@
       "license": "MIT"
     },
     "node_modules/npm/node_modules/are-we-there-yet": {
-      "version": "4.0.1",
+      "version": "4.0.2",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
-      "dependencies": {
-        "delegates": "^1.0.0",
-        "readable-stream": "^4.1.0"
-      },
       "engines": {
         "node": "^14.17.0 || ^16.13.0 || >=18.0.0"
       }
@@ -6105,26 +6063,6 @@
       "inBundle": true,
       "license": "MIT"
     },
-    "node_modules/npm/node_modules/base64-js": {
-      "version": "1.5.1",
-      "dev": true,
-      "funding": [
-        {
-          "type": "github",
-          "url": "https://github.com/sponsors/feross"
-        },
-        {
-          "type": "patreon",
-          "url": "https://www.patreon.com/feross"
-        },
-        {
-          "type": "consulting",
-          "url": "https://feross.org/support"
-        }
-      ],
-      "inBundle": true,
-      "license": "MIT"
-    },
     "node_modules/npm/node_modules/bin-links": {
       "version": "4.0.3",
       "dev": true,
@@ -6158,30 +6096,6 @@
         "balanced-match": "^1.0.0"
       }
     },
-    "node_modules/npm/node_modules/buffer": {
-      "version": "6.0.3",
-      "dev": true,
-      "funding": [
-        {
-          "type": "github",
-          "url": "https://github.com/sponsors/feross"
-        },
-        {
-          "type": "patreon",
-          "url": "https://www.patreon.com/feross"
-        },
-        {
-          "type": "consulting",
-          "url": "https://feross.org/support"
-        }
-      ],
-      "inBundle": true,
-      "license": "MIT",
-      "dependencies": {
-        "base64-js": "^1.3.1",
-        "ieee754": "^1.2.1"
-      }
-    },
     "node_modules/npm/node_modules/builtins": {
       "version": "5.0.1",
       "dev": true,
@@ -6192,7 +6106,7 @@
       }
     },
     "node_modules/npm/node_modules/cacache": {
-      "version": "18.0.1",
+      "version": "18.0.2",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -6487,12 +6401,6 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
-    "node_modules/npm/node_modules/delegates": {
-      "version": "1.0.0",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT"
-    },
     "node_modules/npm/node_modules/diff": {
       "version": "5.1.0",
       "dev": true,
@@ -6539,24 +6447,6 @@
       "inBundle": true,
       "license": "MIT"
     },
-    "node_modules/npm/node_modules/event-target-shim": {
-      "version": "5.0.1",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT",
-      "engines": {
-        "node": ">=6"
-      }
-    },
-    "node_modules/npm/node_modules/events": {
-      "version": "3.3.0",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT",
-      "engines": {
-        "node": ">=0.8.x"
-      }
-    },
     "node_modules/npm/node_modules/exponential-backoff": {
       "version": "3.1.1",
       "dev": true,
@@ -6752,26 +6642,6 @@
         "node": ">=0.10.0"
       }
     },
-    "node_modules/npm/node_modules/ieee754": {
-      "version": "1.2.1",
-      "dev": true,
-      "funding": [
-        {
-          "type": "github",
-          "url": "https://github.com/sponsors/feross"
-        },
-        {
-          "type": "patreon",
-          "url": "https://www.patreon.com/feross"
-        },
-        {
-          "type": "consulting",
-          "url": "https://feross.org/support"
-        }
-      ],
-      "inBundle": true,
-      "license": "BSD-3-Clause"
-    },
     "node_modules/npm/node_modules/ignore-walk": {
       "version": "6.0.4",
       "dev": true,
@@ -6963,7 +6833,7 @@
       }
     },
     "node_modules/npm/node_modules/libnpmdiff": {
-      "version": "6.0.4",
+      "version": "6.0.5",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -6983,7 +6853,7 @@
       }
     },
     "node_modules/npm/node_modules/libnpmexec": {
-      "version": "7.0.5",
+      "version": "7.0.6",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -7005,7 +6875,7 @@
       }
     },
     "node_modules/npm/node_modules/libnpmfund": {
-      "version": "5.0.2",
+      "version": "5.0.3",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -7043,7 +6913,7 @@
       }
     },
     "node_modules/npm/node_modules/libnpmpack": {
-      "version": "6.0.4",
+      "version": "6.0.5",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -7468,7 +7338,7 @@
       }
     },
     "node_modules/npm/node_modules/npm-packlist": {
-      "version": "8.0.1",
+      "version": "8.0.2",
       "dev": true,
       "inBundle": true,
       "license": "ISC",
@@ -7636,7 +7506,7 @@
       }
     },
     "node_modules/npm/node_modules/postcss-selector-parser": {
-      "version": "6.0.13",
+      "version": "6.0.15",
       "dev": true,
       "inBundle": true,
       "license": "MIT",
@@ -7657,15 +7527,6 @@
         "node": "^14.17.0 || ^16.13.0 || >=18.0.0"
       }
     },
-    "node_modules/npm/node_modules/process": {
-      "version": "0.11.10",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT",
-      "engines": {
-        "node": ">= 0.6.0"
-      }
-    },
     "node_modules/npm/node_modules/promise-all-reject-late": {
       "version": "1.0.1",
       "dev": true,
@@ -7772,22 +7633,6 @@
         "node": "^14.17.0 || ^16.13.0 || >=18.0.0"
       }
     },
-    "node_modules/npm/node_modules/readable-stream": {
-      "version": "4.4.2",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT",
-      "dependencies": {
-        "abort-controller": "^3.0.0",
-        "buffer": "^6.0.3",
-        "events": "^3.3.0",
-        "process": "^0.11.10",
-        "string_decoder": "^1.3.0"
-      },
-      "engines": {
-        "node": "^12.22.0 || ^14.17.0 || >=16.0.0"
-      }
-    },
     "node_modules/npm/node_modules/retry": {
       "version": "0.12.0",
       "dev": true,
@@ -7797,26 +7642,6 @@
         "node": ">= 4"
       }
     },
-    "node_modules/npm/node_modules/safe-buffer": {
-      "version": "5.2.1",
-      "dev": true,
-      "funding": [
-        {
-          "type": "github",
-          "url": "https://github.com/sponsors/feross"
-        },
-        {
-          "type": "patreon",
-          "url": "https://www.patreon.com/feross"
-        },
-        {
-          "type": "consulting",
-          "url": "https://feross.org/support"
-        }
-      ],
-      "inBundle": true,
-      "license": "MIT"
-    },
     "node_modules/npm/node_modules/safer-buffer": {
       "version": "2.1.2",
       "dev": true,
@@ -7987,15 +7812,6 @@
         "node": "^14.17.0 || ^16.13.0 || >=18.0.0"
       }
     },
-    "node_modules/npm/node_modules/string_decoder": {
-      "version": "1.3.0",
-      "dev": true,
-      "inBundle": true,
-      "license": "MIT",
-      "dependencies": {
-        "safe-buffer": "~5.2.0"
-      }
-    },
     "node_modules/npm/node_modules/string-width": {
       "version": "4.2.3",
       "dev": true,
@@ -9322,9 +9138,9 @@
       "dev": true
     },
     "node_modules/safe-regex-test": {
-      "version": "1.0.1",
+      "version": "1.0.2",
-      "resolved": "https://registry.npmjs.org/safe-regex-test/-/safe-regex-test-1.0.1.tgz",
+      "resolved": "https://registry.npmjs.org/safe-regex-test/-/safe-regex-test-1.0.2.tgz",
-      "integrity": "sha512-Y5NejJTTliTyY4H7sipGqY+RX5P87i3F7c4Rcepy72nq+mNLhIsD0W4c7kEmduMDQCSqtPsXPlSTsFhh2LQv+g==",
+      "integrity": "sha512-83S9w6eFq12BBIJYvjMux6/dkirb8+4zJRA9cxNBVb7Wq5fJBW+Xze48WqR8pxua7bDuAaaAxtVVd4Idjp1dBQ==",
       "dev": true,
       "dependencies": {
         "call-bind": "^1.0.5",

package.json

@@ -44,27 +44,25 @@
     "postpublish": "pinst --enable"
   },
   "dependencies": {
-    "markdown-it": "14.0.0",
+    "markdown-it": "14.0.0"
-    "markdownlint-rule-helpers": "0.24.0"
   },
   "devDependencies": {
     "@commitlint/cli": "18.4.4",
     "@commitlint/config-conventional": "18.4.4",
     "@types/markdown-it": "13.0.7",
-    "@types/node": "20.10.8",
+    "@types/node": "20.11.0",
     "editorconfig-checker": "5.1.2",
     "eslint": "8.56.0",
     "eslint-config-conventions": "13.1.0",
     "eslint-config-prettier": "9.1.0",
     "eslint-plugin-import": "2.29.1",
-    "eslint-plugin-prettier": "5.1.2",
+    "eslint-plugin-prettier": "5.1.3",
     "eslint-plugin-promise": "6.1.1",
     "eslint-plugin-unicorn": "50.0.1",
     "husky": "8.0.3",
     "lint-staged": "15.2.0",
     "markdownlint": "0.33.0",
     "markdownlint-cli2": "0.11.0",
-    "markdownlint-rule-helpers": "0.24.0",
     "pinst": "3.0.0",
     "prettier": "3.1.1",
     "semantic-release": "22.0.12",

src/index.js

@@ -3,8 +3,8 @@
 const { pathToFileURL } = require("node:url")
 const fs = require("node:fs")
 
+const { filterTokens } = require("./markdownlint-rule-helpers/helpers.js")
 const {
-  filterTokens,
   convertHeadingToHTMLFragment,
   getMarkdownHeadings,
   getMarkdownIdOrAnchorNameFragments,

src/markdownlint-rule-helpers/helpers.js

@@ -0,0 +1,38 @@
+/**
+ * Dependency Vendoring of `markdownlint-rule-helpers`
+ * @see https://www.npmjs.com/package/markdownlint-rule-helpers
+ */
+
+/** @typedef {import('markdownlint').RuleParams} MarkdownLintRuleParams */
+/** @typedef {import('markdownlint').MarkdownItToken} MarkdownItToken */
+
+/**
+ * Calls the provided function for each matching token.
+ *
+ * @param {MarkdownLintRuleParams} params RuleParams instance.
+ * @param {string} type Token type identifier.
+ * @param {(token: MarkdownItToken) => void} handler Callback function.
+ * @returns {void}
+ */
+const filterTokens = (params, type, handler) => {
+  for (const token of params.tokens) {
+    if (token.type === type) {
+      handler(token)
+    }
+  }
+}
+
+/**
+ * Gets a Regular Expression for matching the specified HTML attribute.
+ *
+ * @param {string} name HTML attribute name.
+ * @returns {RegExp} Regular Expression for matching.
+ */
+const getHtmlAttributeRe = (name) => {
+  return new RegExp(`\\s${name}\\s*=\\s*['"]?([^'"\\s>]*)`, "iu")
+}
+
+module.exports = {
+  filterTokens,
+  getHtmlAttributeRe,
+}

src/utils.js

@@ -1,25 +1,6 @@
 const MarkdownIt = require("markdown-it")
-// @ts-ignore
-const { getHtmlAttributeRe } = require("markdownlint-rule-helpers")
 
-/** @typedef {import('markdownlint').RuleParams} MarkdownLintRuleParams */
+const { getHtmlAttributeRe } = require("./markdownlint-rule-helpers/helpers.js")
-/** @typedef {import('markdownlint').MarkdownItToken} MarkdownItToken */
-
-/**
- * Calls the provided function for each matching token.
- *
- * @param {MarkdownLintRuleParams} params RuleParams instance.
- * @param {string} type Token type identifier.
- * @param {(token: MarkdownItToken) => void} handler Callback function.
- * @returns {void}
- */
-const filterTokens = (params, type, handler) => {
-  for (const token of params.tokens) {
-    if (token.type === type) {
-      handler(token)
-    }
-  }
-}
 
 /**
  * Converts a Markdown heading into an HTML fragment according to the rules
@@ -114,12 +95,12 @@ const getMarkdownIdOrAnchorNameFragments = (content) => {
   for (const token of tokens) {
     const anchorMatch =
       anchorIdRe.exec(token.content) || anchorNameRe.exec(token.content)
-    if (!anchorMatch || anchorMatch.length === 0) {
+    if (anchorMatch == null) {
       continue
     }
 
     const anchorIdOrName = anchorMatch[1]
-    if (anchorIdOrName.length <= 0) {
+    if (anchorIdOrName == null || anchorIdOrName.length <= 0) {
       continue
     }
 
@@ -133,7 +114,6 @@ const getMarkdownIdOrAnchorNameFragments = (content) => {
 }
 
 module.exports = {
-  filterTokens,
   convertHeadingToHTMLFragment,
   getMarkdownHeadings,
   getMarkdownIdOrAnchorNameFragments,