Adding dependency check scripts.

package.json

@@ -9,6 +9,7 @@
     "@types/node": "20.10.0",
     "@types/proper-lockfile": "^4.1.4",
     "@typescript-eslint/parser": "6.9.0",
+    "depcheck": "^1.4.7",
     "esbuild": "^0.18.17",
     "esbuild-node-externals": "^1.14.0",
     "eslint": "^8.52.0",

scripts/depcheck.js

@@ -0,0 +1,29 @@
+#!/usr/bin/node
+
+const depcheck = require("depcheck")
+
+function filterResults(missing) {
+  if (missing.src) {
+    delete missing.src
+  }
+  return missing
+}
+
+function printMissing(missing) {
+  for (let [key, value] of Object.entries(filterResults(missing))) {
+    console.log(`Package ${key} missing in: ${value.join(", ")}`)
+  }
+}
+
+depcheck(process.cwd(), {
+  ignorePatterns: ["dist"],
+  skipMissing: false,
+}).then(results => {
+  if (Object.values(filterResults(results.missing)).length > 0) {
+    printMissing(results.missing)
+    console.error("Missing packages found - stopping.")
+    process.exit(-1)
+  } else {
+    console.log("No missing dependencies.")
+  }
+})