refactor(examples): Add missing function return types (#26003)

In preparation for globally enabling an eslint rule that requires them.

Author: Josmithr

examples/apps/staging/src/container/groceryList/groceryList.ts

@@ -74,7 +74,7 @@ class GroceryList implements IGroceryList {
 		}
 	}
 
-	public readonly addItem = (name: string) => {
+	public readonly addItem = (name: string): void => {
 		// Use timestamp as a hack for a consistent sortable order.
 		this.map.set(`${Date.now()}-${uuid()}`, name);
 	};
@@ -85,11 +85,11 @@ class GroceryList implements IGroceryList {
 		);
 	};
 
-	public readonly removeItem = (id: string) => {
+	public readonly removeItem = (id: string): void => {
 		this.map.delete(id);
 	};
 
-	private readonly onMapValueChanged = (changed: IValueChanged) => {
+	private readonly onMapValueChanged = (changed: IValueChanged): void => {
 		const changedId = changed.key;
 		const newName = this.map.get(changedId);
 		if (newName === undefined) {

examples/apps/staging/src/container/suggestionGroceryList.ts

@@ -40,7 +40,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 	 */
 	private readonly _suggestionGroceryItems = new Map<string, SuggestionGroceryItem>();
 	private _inStagingMode = false;
-	public get inStagingMode() {
+	public get inStagingMode(): boolean {
 		return this._inStagingMode;
 	}
 
@@ -86,7 +86,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		}
 	}
 
-	public readonly addItem = (name: string) => {
+	public readonly addItem = (name: string): void => {
 		if (this._inStagingMode) {
 			// Use timestamp as a hack for a consistent sortable order.  Prefixed with 'z' to sort last.
 			const suggestedAddition = new SuggestionGroceryItem(
@@ -116,7 +116,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		);
 	};
 
-	public readonly removeItem = (id: string) => {
+	public readonly removeItem = (id: string): void => {
 		if (this._inStagingMode) {
 			const suggestedRemoval = this._suggestionGroceryItems.get(id);
 			if (suggestedRemoval !== undefined) {
@@ -133,8 +133,8 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		}
 	};
 
-	public readonly getSuggestions = () => {
-		const asyncGetSuggestions = async () => {
+	public readonly getSuggestions = (): void => {
+		const asyncGetSuggestions = async (): Promise<void> => {
 			const { adds, removals } = await getChangesFromHealthBot(this.groceryList);
 			// Check to make sure we are still in staging mode after we get the results - if not, then just
 			// discard the suggestions.  Alternatively, we could wait for the network call to return before
@@ -154,7 +154,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		asyncGetSuggestions().catch(console.error);
 	};
 
-	public readonly acceptSuggestions = () => {
+	public readonly acceptSuggestions = (): void => {
 		const adds = [...this._suggestionGroceryItems.values()].filter(
 			(item) => item.suggestion === "add",
 		);
@@ -175,7 +175,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		this._events.emit("leaveStagingMode");
 	};
 
-	public readonly rejectSuggestions = () => {
+	public readonly rejectSuggestions = (): void => {
 		for (const item of this._suggestionGroceryItems.values()) {
 			if (item.suggestion === "add") {
 				item.removeItem();
@@ -188,7 +188,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		this._events.emit("leaveStagingMode");
 	};
 
-	private readonly onItemAdded = (item: IGroceryItem) => {
+	private readonly onItemAdded = (item: IGroceryItem): void => {
 		const addedItem = new SuggestionGroceryItem(
 			item.id,
 			item.name,
@@ -207,7 +207,7 @@ export class SuggestionGroceryList implements ISuggestionGroceryList {
 		this._events.emit("itemAdded", addedItem);
 	};
 
-	private readonly onItemRemoved = (item: IGroceryItem) => {
+	private readonly onItemRemoved = (item: IGroceryItem): void => {
 		const removedItem = this._suggestionGroceryItems.get(item.id);
 		this._suggestionGroceryItems.delete(item.id);
 		this._events.emit("itemRemoved", removedItem);

examples/apps/staging/src/start.ts

@@ -24,15 +24,15 @@ import {
 } from "./container/index.js";
 import { AppView, DebugView } from "./view/index.js";
 
-const updateTabForId = (id: string) => {
+const updateTabForId = (id: string): void => {
 	// Update the URL with the actual ID
 	location.hash = id;
 
 	// Put the ID in the tab title
 	document.title = id;
 };
 
-const render = (groceryList: ISuggestionGroceryList) => {
+const render = (groceryList: ISuggestionGroceryList): void => {
 	const appDiv = document.getElementById("app") as HTMLDivElement;
 	const appRoot = createRoot(appDiv);
 	appRoot.render(createElement(AppView, { groceryList }));

examples/apps/staging/src/view/appView.tsx

@@ -13,11 +13,11 @@ export interface IAppViewProps {
 	groceryList: ISuggestionGroceryList;
 }
 
-export const AppView: FC<IAppViewProps> = ({ groceryList }: IAppViewProps) => {
+export const AppView: FC<IAppViewProps> = ({ groceryList }: IAppViewProps): JSX.Element => {
 	const [inStagingMode, setInStagingMode] = useState<boolean>(groceryList.inStagingMode);
 
 	useEffect(() => {
-		const handleStagingModeChanged = () => {
+		const handleStagingModeChanged = (): void => {
 			setInStagingMode(groceryList.inStagingMode);
 		};
 		groceryList.events.on("enterStagingMode", handleStagingModeChanged);
@@ -30,10 +30,10 @@ export const AppView: FC<IAppViewProps> = ({ groceryList }: IAppViewProps) => {
 
 	let actions;
 	if (inStagingMode) {
-		const onAcceptChanges = () => {
+		const onAcceptChanges = (): void => {
 			groceryList.acceptSuggestions();
 		};
-		const onRejectChanges = () => {
+		const onRejectChanges = (): void => {
 			groceryList.rejectSuggestions();
 		};
 		actions = (

examples/apps/staging/src/view/groceryListView.tsx

@@ -46,10 +46,10 @@ interface IAddItemViewProps {
 	readonly addItem: (name: string) => void;
 }
 
-const AddItemView: FC<IAddItemViewProps> = ({ addItem }: IAddItemViewProps) => {
+const AddItemView: FC<IAddItemViewProps> = ({ addItem }: IAddItemViewProps): JSX.Element => {
 	const nameRef = useRef<HTMLInputElement>(null);
 
-	const onAddItemButtonClick = () => {
+	const onAddItemButtonClick = (): void => {
 		if (nameRef.current === null) {
 			throw new Error("Couldn't get the new item info");
 		}
@@ -91,7 +91,7 @@ export const GroceryListView: FC<IGroceryListViewProps> = ({
 		groceryList.getItems(),
 	);
 	useEffect(() => {
-		const updateItems = () => {
+		const updateItems = (): void => {
 			// TODO: This blows away all the grocery items, making the granular add/delete events
 			// not so useful.  Is there a good way to make a more granular change?
 			setGroceryItems(groceryList.getItems());

examples/benchmarks/odspsnapshotfetch-perftestapp/src/fetchApp.ts

@@ -11,7 +11,7 @@ import { MockLogger } from "@fluidframework/telemetry-utils/internal";
 
 import { OdspSampleCache } from "./odspPersistantCache.js";
 
-export function start(div: HTMLDivElement, odspAccessToken: string) {
+export function start(div: HTMLDivElement, odspAccessToken: string): void {
 	const binaryDiv = document.createElement("div");
 	binaryDiv.style.minHeight = "400px";
 	const binaryText = document.createElement("div");
@@ -90,7 +90,7 @@ export function start(div: HTMLDivElement, odspAccessToken: string) {
 }
 
 // eslint-disable-next-line import-x/no-deprecated
-function fetchButtonClick(mockLogger: MockLogger, div: HTMLDivElement) {
+function fetchButtonClick(mockLogger: MockLogger, div: HTMLDivElement): void {
 	const fields = new Set([
 		"eventName",
 		"attempts",

examples/benchmarks/odspsnapshotfetch-perftestapp/src/odspPersistantCache.ts

@@ -20,7 +20,7 @@ export class OdspSampleCache implements IPersistedCache {
 		return this.cache.get(getKeyForCacheEntry(entry));
 	}
 
-	async put(entry: ICacheEntry, value: any) {
+	async put(entry: ICacheEntry, value: any): Promise<void> {
 		this.cache.set(getKeyForCacheEntry(entry), value);
 	}
 

examples/benchmarks/tablebench/src/app.ts

@@ -10,11 +10,11 @@ import { Table } from "./tree/index.js";
 export { generateTable };
 export { Table };
 
-export async function initApp() {
+export async function initApp(): Promise<void> {
 	const { view } = await initFluid();
 
 	// eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-	document.getElementById("run")!.addEventListener("click", () => {
+	document.getElementById("run")!.addEventListener("click", (): void => {
 		performance.mark("start");
 
 		for (const row of view.root) {

examples/benchmarks/tablebench/src/azure.ts

@@ -31,7 +31,7 @@ const containerSchema = {
 
 const config = new TreeViewConfiguration({ schema: Table });
 
-export async function initFluid() {
+export async function initFluid(): Promise<{ view: TreeView<typeof Table> }> {
 	let container;
 	let view: TreeView<typeof Table>;
 
@@ -41,7 +41,7 @@ export async function initFluid() {
 		view = tree.viewWith(config);
 		view.initialize(generateTable(10000));
 		// TODO: Waiting for 'attach()' is a work around for https://dev.azure.com/fluidframework/internal/_workitems/edit/6805
-		await container.attach().then((containerId) => (location.hash = containerId));
+		await container.attach().then((containerId: string) => (location.hash = containerId));
 	} else {
 		({ container } = await client.getContainer(
 			location.hash.substring(1),

examples/benchmarks/tablebench/src/data.ts

@@ -3,8 +3,8 @@
  * Licensed under the MIT License.
  */
 
-import { IRandom, makeRandom } from "@fluid-private/stochastic-test-utils";
-import { InsertableTypedNode } from "@fluidframework/tree";
+import { type IRandom, makeRandom } from "@fluid-private/stochastic-test-utils";
+import type { InsertableTypedNode } from "@fluidframework/tree";
 
 import { Row } from "./tree/index.js";
 
@@ -24,7 +24,7 @@ export function generateRow(random: IRandom): InsertableTypedNode<typeof Row> {
 		["Baby Food", 255.28, 159.42],
 	]);
 
-	const toDollars = (n: number) => Math.round(n * 100) / 100;
+	const toDollars = (n: number): number => Math.round(n * 100) / 100;
 
 	const unitsSold = random.integer(2, 10000);
 	const totalRevenue = toDollars(unitPrice * unitsSold);
@@ -239,7 +239,7 @@ export function generateRow(random: IRandom): InsertableTypedNode<typeof Row> {
 	};
 }
 
-export function generateTable(rows: number, seed = 1) {
+export function generateTable(rows: number, seed = 1): InsertableTypedNode<typeof Row>[] {
 	const random = makeRandom(seed);
 
 	return Array.from({ length: rows }, () => generateRow(random)).sort(