broadcastchannel: polyfill close method - closes #61

broadcastchannel.js

@@ -44,7 +44,11 @@ class LocalStoragePolyfill {
      * @type {null|function({data:ArrayBuffer}):void}
      */
     this.onmessage = null
-    storage.onChange(e => e.key === room && this.onmessage !== null && this.onmessage({ data: buffer.fromBase64(e.newValue || '') }))
+    /**
+     * @param {any} e
+     */
+    this._onChange = e => e.key === room && this.onmessage !== null && this.onmessage({ data: buffer.fromBase64(e.newValue || '') })
+    storage.onChange(this._onChange)
   }
 
   /**
@@ -53,6 +57,10 @@ class LocalStoragePolyfill {
   postMessage (buf) {
     storage.varStorage.setItem(this.room, buffer.toBase64(buffer.createUint8ArrayFromArrayBuffer(buf)))
   }
+
+  close () {
+    storage.offChange(this._onChange)
+  }
 }
 /* c8 ignore stop */
 

storage.js

@@ -1,4 +1,4 @@
-/* global localStorage, addEventListener */
+/* eslint-env browser */
 
 /**
  * Isomorphic variable storage.
@@ -61,3 +61,12 @@ export const varStorage = _localStorage
  */
 /* c8 ignore next */
 export const onChange = eventHandler => usePolyfill || addEventListener('storage', /** @type {any} */ (eventHandler))
+
+/**
+ * A polyfill for `removeEventListener('storage', event => {..})` that does nothing if the polyfill is being used.
+ *
+ * @param {function({ key: string, newValue: string, oldValue: string }): void} eventHandler
+ * @function
+ */
+/* c8 ignore next */
+export const offChange = eventHandler => usePolyfill || removeEventListener('storage', /** @type {any} */ (eventHandler))

tsconfig.json

@@ -17,7 +17,7 @@
     "paths": {
       "lib0/*": ["./*"],
       "lib0/webcrypto": ["./webcrypto.browser.js"],
-      "lib0/performance": ["./performance.browser.js"],
+      "lib0/performance": ["./performance.node.js"],
       "lib0/logging": ["./logging.node.js"]
     }
   },