Stable references for events in TS and JS

Author: Raicuparta

src/lang/globals.js

@@ -36,29 +36,40 @@ import * as TAURI_API_EVENT from "@tauri-apps/api/event";
  * }}
  */
 function __makeEvents__(mappings) {
+	const eventsProxies = Object.fromEntries(
+		Object.keys(mappings).map((event) => {
+			const name = mappings[event];
+
+			const proxyHandlerGet = {
+				listen: (arg) => TAURI_API_EVENT.listen(name, arg),
+				once: (arg) => TAURI_API_EVENT.once(name, arg),
+				emit: (arg) => TAURI_API_EVENT.emit(name, arg),
+			};
+
+			const proxy = new Proxy(
+				(() => {}),
+				{
+					apply: (_, __, [window]) => ({
+							listen: (arg) => window.listen(name, arg),
+							once: (arg) => window.once(name, arg),
+							emit: (arg) => window.emit(name, arg),
+					}),
+					get: (_, command) => proxyHandlerGet[command],
+				},
+			);
+
+			return [event, proxy];
+		})
+	);
+
 	return new Proxy(
 		{},
 		{
 			get: (_, event) => {
-				const name = mappings[event];
-
-				new Proxy(() => {}, {
-					apply: (_, __, [window]) => ({
-						listen: (arg) => window.listen(name, arg),
-						once: (arg) => window.once(name, arg),
-						emit: (arg) => window.emit(name, arg),
-					}),
-					get: (_, command) => {
-						switch (command) {
-							case "listen":
-								return (arg) => TAURI_API_EVENT.listen(name, arg);
-							case "once":
-								return (arg) => TAURI_API_EVENT.once(name, arg);
-							case "emit":
-								return (arg) => TAURI_API_EVENT.emit(name, arg);
-						}
-					},
-				});
+				if (typeof event === "string") {
+					return eventsProxies[event];
+				}
+				return undefined;
 			},
 		},
 	);

src/lang/globals.ts

@@ -1,29 +1,31 @@
 import {
-	invoke as TAURI_INVOKE,
-	Channel as TAURI_CHANNEL,
+  invoke as TAURI_INVOKE,
+  Channel as TAURI_CHANNEL,
 } from "@tauri-apps/api/core";
 import * as TAURI_API_EVENT from "@tauri-apps/api/event";
 import { type WebviewWindow as __WebviewWindow__ } from "@tauri-apps/api/webviewWindow";
 
 type __EventObj__<T> = {
-	listen: (
-		cb: TAURI_API_EVENT.EventCallback<T>,
-	) => ReturnType<typeof TAURI_API_EVENT.listen<T>>;
-	once: (
-		cb: TAURI_API_EVENT.EventCallback<T>,
-	) => ReturnType<typeof TAURI_API_EVENT.once<T>>;
-	emit: null extends T
-		? (payload?: T) => ReturnType<typeof TAURI_API_EVENT.emit>
-		: (payload: T) => ReturnType<typeof TAURI_API_EVENT.emit>;
+  listen: (
+    cb: TAURI_API_EVENT.EventCallback<T>
+  ) => ReturnType<typeof TAURI_API_EVENT.listen<T>>;
+  once: (
+    cb: TAURI_API_EVENT.EventCallback<T>
+  ) => ReturnType<typeof TAURI_API_EVENT.once<T>>;
+  emit: null extends T
+    ? (payload?: T) => ReturnType<typeof TAURI_API_EVENT.emit>
+    : (payload: T) => ReturnType<typeof TAURI_API_EVENT.emit>;
 };
 
 export type Result<T, E> =
-	| { status: "ok"; data: T }
-	| { status: "error"; error: E };
+  | { status: "ok"; data: T }
+  | { status: "error"; error: E };
 
 function __makeEvents__<T extends Record<string, any>>(
 	mappings: Record<keyof T, string>,
 ) {
+	const eventObjects: Record<string, T[keyof T]> = {};
+
 	return new Proxy(
 		{} as unknown as {
 			[K in keyof T]: __EventObj__<T[K]> & {
@@ -34,23 +36,30 @@ function __makeEvents__<T extends Record<string, any>>(
 			get: (_, event) => {
 				const name = mappings[event as keyof T];
 
-				return new Proxy((() => {}) as any, {
-					apply: (_, __, [window]: [__WebviewWindow__]) => ({
-						listen: (arg: any) => window.listen(name, arg),
-						once: (arg: any) => window.once(name, arg),
-						emit: (arg: any) => window.emit(name, arg),
-					}),
-					get: (_, command: keyof __EventObj__<any>) => {
-						switch (command) {
-							case "listen":
-								return (arg: any) => TAURI_API_EVENT.listen(name, arg);
-							case "once":
-								return (arg: any) => TAURI_API_EVENT.once(name, arg);
-							case "emit":
-								return (arg: any) => TAURI_API_EVENT.emit(name, arg);
-						}
-					},
-				});
+				let eventObject = eventObjects[name];
+				if (!eventObject) {
+					eventObject = new Proxy((() => {}) as any, {
+						apply: (_, __, [window]: [__WebviewWindow__]) => ({
+							listen: (arg: any) => window.listen(name, arg),
+							once: (arg: any) => window.once(name, arg),
+							emit: (arg: any) => window.emit(name, arg),
+						}),
+						get: (_, command: keyof __EventObj__<any>) => {
+							switch (command) {
+								case "listen":
+									return (arg: any) => TAURI_API_EVENT.listen(name, arg);
+								case "once":
+									return (arg: any) => TAURI_API_EVENT.once(name, arg);
+								case "emit":
+									return (arg: any) => TAURI_API_EVENT.emit(name, arg);
+							}
+						},
+					});
+
+					eventObjects[name] = eventObject;
+				}
+
+				return eventObject;
 			},
 		},
 	);