Add explicit function return types

packages/react-pdf/src/Document.spec.tsx

@@ -12,6 +12,7 @@ import { makeAsyncCallback, loadPDF, muteConsole, restoreConsole } from '../../.
 
 import type { PDFDocumentProxy } from 'pdfjs-dist';
 import type { ScrollPageIntoViewArgs } from './shared/types.js';
+import type LinkService from './LinkService.js';
 
 const pdfFile = loadPDF('./../../__mocks__/_pdf.pdf');
 const pdfFile2 = loadPDF('./../../__mocks__/_pdf2.pdf');
@@ -433,7 +434,8 @@ describe('Document', () => {
 
       const onItemClick = vi.fn();
       const instance = createRef<{
-        pages: React.RefObject<Record<string, unknown>[]>;
+        linkService: React.RefObject<LinkService>;
+        pages: React.RefObject<HTMLDivElement[]>;
         viewer: React.RefObject<{ scrollPageIntoView: (args: ScrollPageIntoViewArgs) => void }>;
       }>();
 
@@ -473,7 +475,9 @@ describe('Document', () => {
       const { func: onLoadSuccess, promise: onLoadSuccessPromise } = makeAsyncCallback();
 
       const instance = createRef<{
-        pages: React.RefObject<Record<string, unknown>[]>;
+        linkService: React.RefObject<LinkService>;
+        // biome-ignore lint/suspicious/noExplicitAny: Intentional use to simplify the test
+        pages: React.RefObject<any[]>;
         viewer: React.RefObject<{ scrollPageIntoView: (args: ScrollPageIntoViewArgs) => void }>;
       }>();
 

packages/react-pdf/src/Document.tsx

@@ -232,7 +232,14 @@ function isParameterObject(file: File): file is Source {
 /**
  * Loads a document passed using `file` prop.
  */
-const Document = forwardRef(function Document(
+const Document: React.ForwardRefExoticComponent<
+  DocumentProps &
+    React.RefAttributes<{
+      linkService: React.RefObject<LinkService>;
+      pages: React.RefObject<HTMLDivElement[]>;
+      viewer: React.RefObject<{ scrollPageIntoView: (args: ScrollPageIntoViewArgs) => void }>;
+    }>
+> = forwardRef(function Document(
   {
     children,
     className,
@@ -255,7 +262,7 @@ const Document = forwardRef(function Document(
     renderMode,
     rotate,
     ...otherProps
-  }: DocumentProps,
+  },
   ref,
 ) {
   const [sourceState, sourceDispatch] = useResolver<Source | null>();

packages/react-pdf/src/DocumentContext.tsx

@@ -4,4 +4,7 @@ import { createContext } from 'react';
 
 import type { DocumentContextType } from './shared/types.js';
 
-export default createContext<DocumentContextType>(null);
+const documentContext: React.Context<DocumentContextType> =
+  createContext<DocumentContextType>(null);
+
+export default documentContext;

packages/react-pdf/src/LinkService.ts

@@ -49,31 +49,31 @@ export default class LinkService implements IPDFLinkService {
     this.pdfViewer = undefined;
   }
 
-  setDocument(pdfDocument: PDFDocumentProxy) {
+  setDocument(pdfDocument: PDFDocumentProxy): void {
     this.pdfDocument = pdfDocument;
   }
 
-  setViewer(pdfViewer: PDFViewer) {
+  setViewer(pdfViewer: PDFViewer): void {
     this.pdfViewer = pdfViewer;
   }
 
-  setExternalLinkRel(externalLinkRel?: ExternalLinkRel) {
+  setExternalLinkRel(externalLinkRel?: ExternalLinkRel): void {
     this.externalLinkRel = externalLinkRel;
   }
 
-  setExternalLinkTarget(externalLinkTarget?: ExternalLinkTarget) {
+  setExternalLinkTarget(externalLinkTarget?: ExternalLinkTarget): void {
     this.externalLinkTarget = externalLinkTarget;
   }
 
-  setHistory() {
+  setHistory(): void {
     // Intentionally empty
   }
 
-  get pagesCount() {
+  get pagesCount(): number {
     return this.pdfDocument ? this.pdfDocument.numPages : 0;
   }
 
-  get page() {
+  get page(): number {
     invariant(this.pdfViewer, 'PDF viewer is not initialized.');
 
     return this.pdfViewer.currentPageNumber || 0;
@@ -85,7 +85,7 @@ export default class LinkService implements IPDFLinkService {
     this.pdfViewer.currentPageNumber = value;
   }
 
-  get rotation() {
+  get rotation(): number {
     return 0;
   }
 
@@ -147,11 +147,11 @@ export default class LinkService implements IPDFLinkService {
     });
   }
 
-  navigateTo(dest: Dest) {
+  navigateTo(dest: Dest): void {
     this.goToDestination(dest);
   }
 
-  goToPage(pageNumber: number) {
+  goToPage(pageNumber: number): void {
     const pageIndex = pageNumber - 1;
 
     invariant(this.pdfViewer, 'PDF viewer is not initialized.');
@@ -167,41 +167,41 @@ export default class LinkService implements IPDFLinkService {
     });
   }
 
-  addLinkAttributes(link: HTMLAnchorElement, url: string, newWindow: boolean) {
+  addLinkAttributes(link: HTMLAnchorElement, url: string, newWindow: boolean): void {
     link.href = url;
     link.rel = this.externalLinkRel || DEFAULT_LINK_REL;
     link.target = newWindow ? '_blank' : this.externalLinkTarget || '';
   }
 
-  getDestinationHash() {
+  getDestinationHash(): string {
     return '#';
   }
 
-  getAnchorUrl() {
+  getAnchorUrl(): string {
     return '#';
   }
 
-  setHash() {
+  setHash(): void {
     // Intentionally empty
   }
 
-  executeNamedAction() {
+  executeNamedAction(): void {
     // Intentionally empty
   }
 
-  cachePageRef() {
+  cachePageRef(): void {
     // Intentionally empty
   }
 
-  isPageVisible() {
+  isPageVisible(): boolean {
     return true;
   }
 
-  isPageCached() {
+  isPageCached(): boolean {
     return true;
   }
 
-  executeSetOCGState() {
+  executeSetOCGState(): void {
     // Intentionally empty
   }
 }

packages/react-pdf/src/Message.tsx

@@ -3,6 +3,6 @@ type MessageProps = {
   type: 'error' | 'loading' | 'no-data';
 };
 
-export default function Message({ children, type }: MessageProps) {
+export default function Message({ children, type }: MessageProps): React.ReactElement {
   return <div className={`react-pdf__message react-pdf__message--${type}`}>{children}</div>;
 }

packages/react-pdf/src/Outline.tsx

@@ -64,7 +64,7 @@ export type OutlineProps = {
  *
  * Should be placed inside `<Document />`. Alternatively, it can have `pdf` prop passed, which can be obtained from `<Document />`'s `onLoadSuccess` callback function.
  */
-export default function Outline(props: OutlineProps) {
+export default function Outline(props: OutlineProps): React.ReactElement | null {
   const documentContext = useDocumentContext();
 
   const mergedProps = { ...documentContext, ...props };

packages/react-pdf/src/OutlineContext.tsx

@@ -4,4 +4,6 @@ import { createContext } from 'react';
 
 import type { OutlineContextType } from './shared/types.js';
 
-export default createContext<OutlineContextType>(null);
+const outlineContext: React.Context<OutlineContextType> = createContext<OutlineContextType>(null);
+
+export default outlineContext;

packages/react-pdf/src/OutlineItem.tsx

@@ -18,7 +18,7 @@ type OutlineItemProps = {
   pdf?: PDFDocumentProxy | false;
 };
 
-export default function OutlineItem(props: OutlineItemProps) {
+export default function OutlineItem(props: OutlineItemProps): React.ReactElement {
   const documentContext = useDocumentContext();
 
   const outlineContext = useOutlineContext();

packages/react-pdf/src/Page.tsx

@@ -300,7 +300,7 @@ export type PageProps = {
  *
  * Should be placed inside `<Document />`. Alternatively, it can have `pdf` prop passed, which can be obtained from `<Document />`'s `onLoadSuccess` callback function, however some advanced functions like linking between pages inside a document may not be working correctly.
  */
-export default function Page(props: PageProps) {
+export default function Page(props: PageProps): React.ReactElement {
   const documentContext = useDocumentContext();
 
   const mergedProps = { ...documentContext, ...props };

packages/react-pdf/src/Page/AnnotationLayer.tsx

@@ -14,7 +14,7 @@ import { cancelRunningTask } from '../shared/utils.js';
 
 import type { Annotations } from '../shared/types.js';
 
-export default function AnnotationLayer() {
+export default function AnnotationLayer(): React.ReactElement {
   const documentContext = useDocumentContext();
   const pageContext = usePageContext();
 

packages/react-pdf/src/Page/Canvas.tsx

@@ -24,7 +24,7 @@ type CanvasProps = {
   canvasRef?: React.Ref<HTMLCanvasElement>;
 };
 
-export default function Canvas(props: CanvasProps) {
+export default function Canvas(props: CanvasProps): React.ReactElement {
   const pageContext = usePageContext();
 
   invariant(pageContext, 'Unable to find Page context.');

packages/react-pdf/src/Page/TextLayer.tsx

@@ -17,7 +17,7 @@ function isTextItem(item: TextItem | TextMarkedContent): item is TextItem {
   return 'str' in item;
 }
 
-export default function TextLayer() {
+export default function TextLayer(): React.ReactElement {
   const pageContext = usePageContext();
 
   invariant(pageContext, 'Unable to find Page context.');

packages/react-pdf/src/PageContext.tsx

@@ -4,4 +4,6 @@ import { createContext } from 'react';
 
 import type { PageContextType } from './shared/types.js';
 
-export default createContext<PageContextType>(null);
+const pageContext: React.Context<PageContextType> = createContext<PageContextType>(null);
+
+export default pageContext;

packages/react-pdf/src/Ref.ts

@@ -7,7 +7,7 @@ export default class Ref {
     this.gen = gen;
   }
 
-  toString() {
+  toString(): string {
     let str = `${this.num}R`;
     if (this.gen !== 0) {
       str += this.gen;

packages/react-pdf/src/StructTree.tsx

@@ -11,7 +11,7 @@ import { cancelRunningTask } from './shared/utils.js';
 
 import type { StructTreeNodeWithExtraAttributes } from './shared/types.js';
 
-export default function StructTree() {
+export default function StructTree(): React.ReactElement | null {
   const pageContext = usePageContext();
 
   invariant(pageContext, 'Unable to find Page context.');

packages/react-pdf/src/StructTreeItem.tsx

@@ -14,7 +14,10 @@ type StructTreeItemProps = {
   node: StructTreeNodeWithExtraAttributes | StructTreeContent;
 };
 
-export default function StructTreeItem({ className, node }: StructTreeItemProps) {
+export default function StructTreeItem({
+  className,
+  node,
+}: StructTreeItemProps): React.ReactElement {
   const attributes = useMemo(() => getAttributes(node), [node]);
 
   // biome-ignore lint/correctness/useExhaustiveDependencies: Looks like a Biome error

packages/react-pdf/src/Thumbnail.tsx

@@ -48,7 +48,7 @@ export type ThumbnailProps = Omit<
  *
  * Should be placed inside `<Document />`. Alternatively, it can have `pdf` prop passed, which can be obtained from `<Document />`'s `onLoadSuccess` callback function.
  */
-export default function Thumbnail(props: ThumbnailProps) {
+export default function Thumbnail(props: ThumbnailProps): React.ReactElement {
   const documentContext = useDocumentContext();
 
   const mergedProps = { ...documentContext, ...props };

packages/react-pdf/src/shared/constants.ts

@@ -56,4 +56,4 @@ export const PDF_ROLE_TO_HTML_ROLE = {
   Artifact: null,
 };
 
-export const HEADING_PATTERN = /^H(\d+)$/;
+export const HEADING_PATTERN: RegExp = /^H(\d+)$/;

packages/react-pdf/src/shared/hooks/useDocumentContext.ts

@@ -2,6 +2,8 @@ import { useContext } from 'react';
 
 import DocumentContext from '../../DocumentContext.js';
 
-export default function useDocumentContext() {
+import type { DocumentContextType } from '../types.js';
+
+export default function useDocumentContext(): DocumentContextType {
   return useContext(DocumentContext);
 }

packages/react-pdf/src/shared/hooks/useOutlineContext.ts

@@ -2,6 +2,8 @@ import { useContext } from 'react';
 
 import OutlineContext from '../../OutlineContext.js';
 
-export default function useOutlineContext() {
+import type { OutlineContextType } from '../types.js';
+
+export default function useOutlineContext(): OutlineContextType {
   return useContext(OutlineContext);
 }

packages/react-pdf/src/shared/hooks/usePageContext.ts

@@ -2,6 +2,8 @@ import { useContext } from 'react';
 
 import PageContext from '../../PageContext.js';
 
-export default function usePageContext() {
+import type { PageContextType } from '../types.js';
+
+export default function usePageContext(): PageContextType {
   return useContext(PageContext);
 }

packages/react-pdf/src/shared/hooks/useResolver.ts

@@ -23,6 +23,6 @@ function reducer<T>(state: State<T>, action: Action<T>): State<T> {
   }
 }
 
-export default function useResolver<T>() {
+export default function useResolver<T>(): [State<T>, React.Dispatch<Action<T>>] {
   return useReducer(reducer<T>, { value: undefined, error: undefined });
 }

packages/react-pdf/src/shared/utils.ts

@@ -7,12 +7,12 @@ import type { PageCallback } from './types.js';
 /**
  * Checks if we're running in a browser environment.
  */
-export const isBrowser = typeof document !== 'undefined';
+export const isBrowser: boolean = typeof document !== 'undefined';
 
 /**
  * Checks whether we're running from a local file system.
  */
-export const isLocalFileSystem = isBrowser && window.location.protocol === 'file:';
+export const isLocalFileSystem: boolean = isBrowser && window.location.protocol === 'file:';
 
 /**
  * Checks whether a variable is defined.
@@ -83,28 +83,28 @@ export function dataURItoByteString(dataURI: unknown): string {
   return unescape(dataString);
 }
 
-export function getDevicePixelRatio() {
+export function getDevicePixelRatio(): number {
   return (isBrowser && window.devicePixelRatio) || 1;
 }
 
 const allowFileAccessFromFilesTip =
   'On Chromium based browsers, you can use --allow-file-access-from-files flag for debugging purposes.';
 
-export function displayCORSWarning() {
+export function displayCORSWarning(): void {
   warning(
     !isLocalFileSystem,
     `Loading PDF as base64 strings/URLs may not work on protocols other than HTTP/HTTPS. ${allowFileAccessFromFilesTip}`,
   );
 }
 
-export function displayWorkerWarning() {
+export function displayWorkerWarning(): void {
   warning(
     !isLocalFileSystem,
     `Loading PDF.js worker may not work on protocols other than HTTP/HTTPS. ${allowFileAccessFromFilesTip}`,
   );
 }
 
-export function cancelRunningTask(runningTask?: { cancel?: () => void } | null) {
+export function cancelRunningTask(runningTask?: { cancel?: () => void } | null): void {
   if (runningTask?.cancel) runningTask.cancel();
 }