update

package/node_modules/@npmcli/arborist/lib/case-insensitive-map.js

@@ -0,0 +1,50 @@
+// package children are represented with a Map object, but many file systems
+// are case-insensitive and unicode-normalizing, so we need to treat
+// node.children.get('FOO') and node.children.get('foo') as the same thing.
+
+module.exports = class CIMap extends Map {
+  #keys = new Map()
+
+  constructor (items = []) {
+    super()
+    for (const [key, val] of items) {
+      this.set(key, val)
+    }
+  }
+
+  #normKey (key) {
+    if (typeof key !== 'string') {
+      return key
+    }
+    return key.normalize('NFKD').toLowerCase()
+  }
+
+  get (key) {
+    const normKey = this.#normKey(key)
+    return this.#keys.has(normKey) ? super.get(this.#keys.get(normKey))
+      : undefined
+  }
+
+  set (key, val) {
+    const normKey = this.#normKey(key)
+    if (this.#keys.has(normKey)) {
+      super.delete(this.#keys.get(normKey))
+    }
+    this.#keys.set(normKey, key)
+    return super.set(key, val)
+  }
+
+  delete (key) {
+    const normKey = this.#normKey(key)
+    if (this.#keys.has(normKey)) {
+      const prevKey = this.#keys.get(normKey)
+      this.#keys.delete(normKey)
+      return super.delete(prevKey)
+    }
+  }
+
+  has (key) {
+    const normKey = this.#normKey(key)
+    return this.#keys.has(normKey) && super.has(this.#keys.get(normKey))
+  }
+}