Added null checks

scripts/AnimeNotifier.ts

@@ -18,7 +18,7 @@ import * as actions from "./Actions"
 export default class AnimeNotifier {
 	app: Application
 	analytics: Analytics
-	user: HTMLElement
+	user: HTMLElement | null
 	title: string
 	webpCheck: Promise<boolean>
 	webpEnabled: boolean
@@ -110,12 +110,18 @@ export default class AnimeNotifier {
 	run() {
 		// Initiate the elements we need
 		this.user = document.getElementById("user")
-		this.app.content = document.getElementById("content")
-		this.app.loading = document.getElementById("loading")
+		this.app.content = document.getElementById("content") as HTMLElement
+		this.app.loading = document.getElementById("loading") as HTMLElement
 
 		// Theme
-		if(this.user && this.user.dataset.pro === "true" && this.user.dataset.theme !== "light") {
-			actions.applyTheme(this.user.dataset.theme)
+		if(this.user && this.user.dataset.pro === "true") {
+			const theme = this.user.dataset.theme
+
+			// Don't apply light theme on load because
+			// it's already the standard theme.
+			if(theme && theme !== "light") {
+				actions.applyTheme(theme)
+			}
 		}
 
 		// Status message
@@ -196,7 +202,7 @@ export default class AnimeNotifier {
 			if(document.title !== this.title) {
 				document.title = this.title
 			}
-		} else {
+		} else if(headers[0].textContent) {
 			document.title = headers[0].textContent
 		}
 	}
@@ -289,7 +295,7 @@ export default class AnimeNotifier {
 	}
 
 	async onBeforeUnload(e: BeforeUnloadEvent) {
-		let message = undefined
+		let message = ""
 
 		// Prevent closing tab on new thread page
 		if(this.app.currentPath === "/new/thread" && document.activeElement.tagName === "TEXTAREA" && (document.activeElement as HTMLTextAreaElement).value.length > 20) {
@@ -325,7 +331,14 @@ export default class AnimeNotifier {
 
 						// Dynamic label assignment to prevent label texts overflowing
 						// and taking horizontal space at page load.
-						element.dataset.label = element.getAttribute("aria-label")
+						let label = element.getAttribute("aria-label")
+
+						if(!label) {
+							console.error("Tooltip without a label:", element)
+							return
+						}
+
+						element.dataset.label = label
 
 						// This is the most expensive call in this whole function,
 						// it consumes about 2-4 ms every time you call it.
@@ -350,7 +363,7 @@ export default class AnimeNotifier {
 
 							let tipChild = document.createElement("div")
 							tipChild.classList.add("tip-offset-child")
-							tipChild.setAttribute("data-label", element.getAttribute("data-label"))
+							tipChild.setAttribute("data-label", element.dataset.label)
 							tipChild.style.left = Math.round(leftOffset) + "px"
 							tipChild.style.width = rect.width + "px"
 							tipChild.style.height = rect.height + "px"
@@ -373,24 +386,25 @@ export default class AnimeNotifier {
 					continue
 				}
 
-				element.addEventListener("dragstart", e => {
-					if(!element.draggable) {
+				element.addEventListener("dragstart", evt => {
+					if(!element.draggable || !evt.dataTransfer) {
 						return
 					}
 
 					let image = element.getElementsByClassName("anime-list-item-image")[0]
 
 					if(image) {
-						e.dataTransfer.setDragImage(image, 0, 0)
+						evt.dataTransfer.setDragImage(image, 0, 0)
 					}
 
 					let name = element.getElementsByClassName("anime-list-item-name")[0]
 
-					e.dataTransfer.setData("text/plain", JSON.stringify({
+					evt.dataTransfer.setData("text/plain", JSON.stringify({
 						api: element.dataset.api,
 						animeTitle: name.textContent
 					}))
-					e.dataTransfer.effectAllowed = "move"
+
+					evt.dataTransfer.effectAllowed = "move"
 				}, false)
 
 				// Prevent re-attaching the same listeners
@@ -404,7 +418,7 @@ export default class AnimeNotifier {
 				}
 
 				element.addEventListener("drop", async e => {
-					let toElement = e.toElement as HTMLElement
+					let toElement = e.toElement
 
 					// Find tab element
 					while(toElement && !toElement.classList.contains("tab")) {
@@ -412,12 +426,12 @@ export default class AnimeNotifier {
 					}
 
 					// Ignore a drop on the current status tab
-					if(!toElement || toElement.classList.contains("active")) {
+					if(!toElement || toElement.classList.contains("active") || !e.dataTransfer) {
 						return
 					}
 
 					let data = e.dataTransfer.getData("text/plain")
-					let json = null
+					let json: any
 
 					try {
 						json = JSON.parse(data)
@@ -433,6 +447,11 @@ export default class AnimeNotifier {
 					e.preventDefault()
 
 					let tabText = toElement.textContent
+
+					if(!tabText) {
+						return
+					}
+
 					let newStatus = tabText.toLowerCase()
 
 					if(newStatus === "on hold") {
@@ -477,7 +496,7 @@ export default class AnimeNotifier {
 				}
 
 				element.addEventListener("dragstart", e => {
-					if(!element.draggable) {
+					if(!element.draggable || !e.dataTransfer) {
 						return
 					}
 
@@ -1236,8 +1255,10 @@ export default class AnimeNotifier {
 			return element.dataset.api
 		}
 
-		let apiObject: HTMLElement
-		let parent = element
+		let apiObject: HTMLElement | undefined
+		let parent: HTMLElement | null
+
+		parent = element
 
 		while(parent = parent.parentElement) {
 			if(parent.dataset.api !== undefined) {
@@ -1246,7 +1267,7 @@ export default class AnimeNotifier {
 			}
 		}
 
-		if(!apiObject) {
+		if(!apiObject || !apiObject.dataset.api) {
 			this.statusMessage.showError("API object not found")
 			throw "API object not found"
 		}
@@ -1269,6 +1290,10 @@ export default class AnimeNotifier {
 	onKeyDown(e: KeyboardEvent) {
 		let activeElement = document.activeElement
 
+		if(!activeElement) {
+			return
+		}
+
 		// Ignore hotkeys on input elements
 		switch(activeElement.tagName) {
 			case "INPUT":

scripts/AudioPlayer.ts

@@ -17,7 +17,7 @@ export default class AudioPlayer {
 	playId = 0
 
 	// Save last request so that we can cancel it
-	lastRequest: XMLHttpRequest
+	lastRequest: XMLHttpRequest | null
 
 	// DOM elements
 	audioPlayer: HTMLElement
@@ -194,7 +194,7 @@ export default class AudioPlayer {
 
 	// Stop
 	stop() {
-		this.arn.currentMediaId = undefined
+		this.arn.currentMediaId = ""
 
 		// Remove CSS class "playing"
 		let playingElements = document.getElementsByClassName("playing")

scripts/DateView.ts

@@ -60,7 +60,7 @@ function getRemainingTime(remaining: number): string {
 }
 
 export function displayAiringDate(element: HTMLElement, now: Date) {
-	if(element.dataset.startDate === "") {
+	if(!element.dataset.startDate || !element.dataset.endDate) {
 		element.textContent = ""
 		return
 	}
@@ -133,8 +133,8 @@ export function displayDate(element: HTMLElement, now: Date) {
 	}
 }
 
-export function displayTime(element: HTMLElement, now: Date) {
-	if(element.dataset.date === "") {
+export function displayTime(element: HTMLElement) {
+	if(!element.dataset.date) {
 		element.textContent = ""
 		return
 	}

scripts/PushManager.ts

@@ -5,7 +5,7 @@ export default class PushManager {
 		this.pushSupported = ("serviceWorker" in navigator) && ("PushManager" in window)
 	}
 
-	async subscription(): Promise<PushSubscription> {
+	async subscription() {
 		if(!this.pushSupported) {
 			return Promise.resolve(null)
 		}
@@ -13,13 +13,9 @@ export default class PushManager {
 		let registration = await navigator.serviceWorker.ready
 		let subscription = await registration.pushManager.getSubscription()
 
-		if(subscription) {
 		return Promise.resolve(subscription)
 	}
 
-		return Promise.resolve(null)
-	}
-
 	async subscribe(userId: string) {
 		if(!this.pushSupported) {
 			return

scripts/ServerEvents.ts

@@ -75,11 +75,16 @@ export default class ServerEvents {
 
 		let button = document.getElementById("load-new-activities")
 
-		if(!button) {
+		if(!button || !button.dataset.count) {
 			return
 		}
 
 		let buttonText = document.getElementById("load-new-activities-text")
+
+		if(!buttonText) {
+			return
+		}
+
 		let newCount = parseInt(button.dataset.count) + 1
 		button.dataset.count = newCount.toString()
 		buttonText.textContent = plural(newCount, "new activity")

scripts/ServiceWorker/ServiceWorker.ts

@@ -99,12 +99,19 @@ function onActivate(evt: any) {
 	// Only keep current version of the cache and delete old caches
 	let cacheWhitelist = [cache.version]
 
+	// Query existing cache keys
 	let deleteOldCache = caches.keys().then(keyList => {
-		return Promise.all(keyList.map(key => {
+		// Create a deletion for every key that's not whitelisted
+		let deletions = keyList.map(key => {
 			if(cacheWhitelist.indexOf(key) === -1) {
 				return caches.delete(key)
 			}
-		}))
+
+			return Promise.resolve(false)
+		})
+
+		// Wait for deletions
+		return Promise.all(deletions)
 	})
 
 	// Immediate claim helps us gain control over a new client immediately
@@ -334,7 +341,7 @@ function broadcast(msg: object) {
 }
 
 // installCache is called when the service worker is installed for the first time.
-async function installCache() {
+function installCache() {
 	let urls = [
 		"/",
 		"/scripts",
@@ -343,19 +350,17 @@ async function installCache() {
 		"https://media.notify.moe/images/elements/noise-strong.png",
 	]
 
-	let promises = []
-
-	for(let url of urls) {
+	let requests = urls.map(async url => {
 		let request = new Request(url, {
 			credentials: "same-origin",
 			mode: "cors"
 		})
 
-		let promise = fetch(request).then(response => cache.store(request, response))
-		promises.push(promise)
-	}
+		const response = await fetch(request)
+		await cache.store(request, response)
+	})
 
-	return Promise.all(promises)
+	return Promise.all(requests)
 }
 
 // Serve network first.

scripts/ServiceWorkerManager.ts

@@ -63,7 +63,13 @@ export default class ServiceWorkerManager {
 	}
 
 	postMessage(message: any) {
-		navigator.serviceWorker.controller.postMessage(JSON.stringify(message))
+		const controller = navigator.serviceWorker.controller
+
+		if(!controller) {
+			return
+		}
+
+		controller.postMessage(JSON.stringify(message))
 	}
 
 	onMessage(evt: MessageEvent) {

scripts/SideBar.ts

@@ -9,8 +9,9 @@ export default class SideBar {
 		this.element = element
 
 		document.body.addEventListener("click", e => {
-			if(document.activeElement.id === "search")
-				return;
+			if(document.activeElement && document.activeElement.id === "search") {
+				return
+			}
 
 			this.hide()
 		})

scripts/TouchController.ts

@@ -15,6 +15,8 @@ export default class TouchController {
 
 		this.downSwipe = this.upSwipe = this.rightSwipe = this.leftSwipe = () => null
 		this.threshold = 3
+		this.x = -1
+		this.y = -1
 	}
 
 	handleTouchStart(evt) {
@@ -23,7 +25,7 @@ export default class TouchController {
 	}
 
 	handleTouchMove(evt) {
-		if(!this.x || !this.y) {
+		if(this.x === -1 || this.y === -1) {
 			return
 		}
 
@@ -47,7 +49,7 @@ export default class TouchController {
 			}
 		}
 
-		this.x = undefined
-		this.y = undefined
+		this.x = -1
+		this.y = -1
 	}
 }

scripts/Utils/uploadWithProgress.ts

@@ -20,8 +20,10 @@ export function uploadWithProgress(url, options: RequestInit, onProgress: ((ev:
 
 		xhr.open(options.method || "GET", url, true)
 
-		for(let k in options.headers || {}) {
-			xhr.setRequestHeader(k, options.headers[k])
+		if(options.headers) {
+			for(let key in options.headers) {
+				xhr.setRequestHeader(key, options.headers[key])
+			}
 		}
 
 		xhr.send(options.body)

tsconfig.json

@@ -6,6 +6,7 @@
 		"baseUrl": ".",
 		"strict": false,
 		"strictFunctionTypes": false,
+		"strictNullChecks": true,
 		"noUnusedLocals": true,
 		"noUnusedParameters": false
 	}