refactor(eslint): enforce prefer-arrow-callback rule

Author: KristjanESPERANTO

clientonly/index.js

@@ -50,11 +50,11 @@ function getServerConfig (url) {
 			let configData = "";
 
 			// Gather incoming data
-			response.on("data", function (chunk) {
+			response.on("data", (chunk) => {
 				configData += chunk;
 			});
 			// Resolve promise at the end of the HTTP/HTTPS stream
-			response.on("end", function () {
+			response.on("end", () => {
 				try {
 					resolve(JSON.parse(configData));
 				} catch (parseError) {
@@ -63,7 +63,7 @@ function getServerConfig (url) {
 			});
 		});
 
-		request.on("error", function (error) {
+		request.on("error", (error) => {
 			reject(new Error(`Unable to read config from server (${url}) (${error.message})`));
 		});
 	});
@@ -122,16 +122,16 @@ async function startClient (config, prefix) {
 		const child = require("node:child_process").spawn(electron, elecParams, options);
 
 		// Pipe all child process output to current stdout
-		child.stdout.on("data", function (buf) {
+		child.stdout.on("data", (buf) => {
 			process.stdout.write(`Client: ${buf}`);
 		});
 
 		// Pipe all child process errors to current stderr
-		child.stderr.on("data", function (buf) {
+		child.stderr.on("data", (buf) => {
 			process.stderr.write(`Client: ${buf}`);
 		});
 
-		child.on("error", function (err) {
+		child.on("error", (err) => {
 			process.stderr.write(`Client: ${err}`);
 		});
 

defaultmodules/alert/alert.js

@@ -124,7 +124,7 @@ Module.register("alert", {
 
 	renderMessage (type, data) {
 		return new Promise((resolve) => {
-			this.nunjucksEnvironment().render(this.getTemplate(type), data, function (err, res) {
+			this.nunjucksEnvironment().render(this.getTemplate(type), data, (err, res) => {
 				if (err) {
 					Log.error("[alert] Failed to render alert", err);
 				}

defaultmodules/calendar/calendar.js

@@ -559,7 +559,7 @@ Module.register("calendar", {
 			}
 			if (limitNumberOfEntries) {
 				// sort entries before clipping
-				by_url_calevents.sort(function (a, b) {
+				by_url_calevents.sort((a, b) => {
 					return a.startDate - b.startDate;
 				});
 				Log.debug(`[calendar] pushing ${by_url_calevents.length} events to total with room for ${remainingEntries}`);
@@ -570,7 +570,7 @@ Module.register("calendar", {
 			}
 		}
 		Log.info(`[calendar] sorting events count=${events.length}`);
-		events.sort(function (a, b) {
+		events.sort((a, b) => {
 			return a.startDate - b.startDate;
 		});
 
@@ -674,7 +674,7 @@ Module.register("calendar", {
 
 	mergeUnique (arr1, arr2) {
 		return arr1.concat(
-			arr2.filter(function (item) {
+			arr2.filter((item) => {
 				return arr1.indexOf(item) === -1;
 			})
 		);

defaultmodules/calendar/calendarfetcherutils.js

@@ -150,7 +150,7 @@ const CalendarFetcherUtils = {
 			}
 		});
 
-		newEvents.sort(function (a, b) {
+		newEvents.sort((a, b) => {
 			return a.startDate - b.startDate;
 		});
 

defaultmodules/calendar/debug.js

@@ -25,12 +25,12 @@ Log.log("Create fetcher ...");
 
 const fetcher = new CalendarFetcher(url, fetchInterval, [], maximumEntries, maximumNumberOfDays, auth);
 
-fetcher.onReceive(function (fetcher) {
+fetcher.onReceive((fetcher) => {
 	Log.log(fetcher.events);
 	process.exit(0);
 });
 
-fetcher.onError(function (fetcher, error) {
+fetcher.onError((fetcher, error) => {
 	Log.log("Fetcher error:", error);
 	process.exit(1);
 });

defaultmodules/newsfeed/newsfeed.js

@@ -182,7 +182,7 @@ Module.register("newsfeed", {
 		const item = this.newsItems[this.activeItem];
 		this.activeItemHash = item.hash;
 
-		const items = this.newsItems.map(function (item) {
+		const items = this.newsItems.map((item) => {
 			item.publishDate = moment(new Date(item.pubdate)).fromNow();
 			return item;
 		});
@@ -250,7 +250,7 @@ Module.register("newsfeed", {
 				}
 			}
 		}
-		newsItems.sort(function (a, b) {
+		newsItems.sort((a, b) => {
 			const dateA = new Date(a.pubdate);
 			const dateB = new Date(b.pubdate);
 			return dateB - dateA;

defaultmodules/weather/weather.js

@@ -329,14 +329,14 @@ Module.register("weather", {
 	addFilters () {
 		this.nunjucksEnvironment().addFilter(
 			"formatTime",
-			function (date) {
+			(date) => {
 				return formatTime(this.config, date);
-			}.bind(this)
+			}
 		);
 
 		this.nunjucksEnvironment().addFilter(
 			"unit",
-			function (value, type, valueUnit) {
+			(value, type, valueUnit) => {
 				let formattedValue;
 				if (type === "temperature") {
 					if (value === null || value === undefined) {
@@ -365,40 +365,40 @@ Module.register("weather", {
 					formattedValue = WeatherUtils.convertWind(value, this.config.windUnits);
 				}
 				return formattedValue;
-			}.bind(this)
+			}
 		);
 
 		this.nunjucksEnvironment().addFilter(
 			"roundValue",
-			function (value) {
+			(value) => {
 				return this.roundValue(value);
-			}.bind(this)
+			}
 		);
 
 		this.nunjucksEnvironment().addFilter(
 			"decimalSymbol",
-			function (value) {
+			(value) => {
 				return value.toString().replace(/\./g, this.config.decimalSymbol);
-			}.bind(this)
+			}
 		);
 
 		this.nunjucksEnvironment().addFilter(
 			"calcNumSteps",
-			function (forecast) {
+			(forecast) => {
 				return Math.min(forecast.length, this.config.maxNumberOfDays);
-			}.bind(this)
+			}
 		);
 
 		this.nunjucksEnvironment().addFilter(
 			"calcNumEntries",
-			function (dataArray) {
+			(dataArray) => {
 				return Math.min(dataArray.length, this.config.maxEntries);
-			}.bind(this)
+			}
 		);
 
 		this.nunjucksEnvironment().addFilter(
 			"opacity",
-			function (currentStep, numSteps) {
+			(currentStep, numSteps) => {
 				if (this.config.fade && this.config.fadePoint < 1) {
 					if (this.config.fadePoint < 0) {
 						this.config.fadePoint = 0;
@@ -413,7 +413,7 @@ Module.register("weather", {
 				} else {
 					return 1;
 				}
-			}.bind(this)
+			}
 		);
 	}
 });

eslint.config.mjs

@@ -82,6 +82,7 @@ export default defineConfig([
 			"no-unneeded-ternary": "error",
 			"no-useless-return": "error",
 			"object-shorthand": ["error", "methods"],
+			"prefer-arrow-callback": "error",
 			"prefer-const": "error",
 			"prefer-template": "error",
 			"require-await": "error"

js/app.js

@@ -44,7 +44,7 @@ if (process.env.MM_CONFIG_FILE) {
 
 // The next part is here to prevent a major exception when there
 // is no internet connection. This could probable be solved better.
-process.on("uncaughtException", function (err) {
+process.on("uncaughtException", (err) => {
 	// ignore strange exceptions under aarch64 coming from systeminformation:
 	if (!err.stack.includes("node_modules/systeminformation")) {
 		Log.error("Whoops! There was an uncaught exception...");

js/electron.js

@@ -122,7 +122,7 @@ function createWindow () {
 	});
 
 	// Set responders for window events.
-	mainWindow.on("closed", function () {
+	mainWindow.on("closed", () => {
 		mainWindow = null;
 	});
 
@@ -146,7 +146,7 @@ function createWindow () {
 }
 
 // Quit when all windows are closed.
-app.on("window-all-closed", function () {
+app.on("window-all-closed", () => {
 	if (process.env.mmTestMode) {
 		// if we are running tests
 		app.quit();
@@ -155,7 +155,7 @@ app.on("window-all-closed", function () {
 	}
 });
 
-app.on("activate", function () {
+app.on("activate", () => {
 
 	/*
 	 * On OS X it's common to re-create a window in the app when the