♻️ Require await in async functions

This commit enables the ESLint rule `require-await` which requires the
use of `await` in async functions and fixes issues that have been
uncovered by this rule. This rule helps to spot unintentional and
leftover `async` keywords.

eslint.config.js

@@ -35,6 +35,7 @@ export default tseslint.config(
  'no-else-return': ['error', { allowElseIf: false }],
  'dot-notation': 'error',
  'one-var': ['error', 'never'],
+ 'require-await': 'error',
  '@typescript-eslint/no-explicit-any': 'off',
  '@typescript-eslint/consistent-type-imports': ['error', { prefer: 'type-imports' }],
  'simple-import-sort/imports': 'error',

src/font-loader.test.ts

@@ -136,7 +136,7 @@ describe('font-loader', () => {
  beforeEach(() => {
  testFont = fakeFont('Test');
  fontLoader = new FontLoader([]);
- fontLoader.loadFont = vi.fn(async (selector: FontSelector) => {
+ fontLoader.loadFont = vi.fn((selector: FontSelector) => {
  if (selector.fontFamily === 'Test') return testFont;
  throw new Error('No such font defined');
  });

src/font-loader.ts

@@ -18,7 +18,7 @@ export class FontLoader {
  this.#fontDefs = fontDefs;
  }
 
- async loadFont(selector: FontSelector): Promise<LoadedFont> {
+ loadFont(selector: FontSelector): LoadedFont {
  if (!this.#fontDefs.length) {
  throw new Error('No fonts defined');
  }

src/image-loader.test.ts

@@ -57,9 +57,9 @@ describe('image-loader', () => {
 
  beforeEach(() => {
  imageLoader = new ImageLoader([]);
- imageLoader.loadImage = vi.fn(async (selector: ImageSelector) => {
- if (selector.name === 'liberty') return { data: libertyJpg };
- if (selector.name === 'torus') return { data: torusPng };
+ imageLoader.loadImage = vi.fn((selector: ImageSelector) => {
+ if (selector.name === 'liberty') return Promise.resolve({ data: libertyJpg });
+ if (selector.name === 'torus') return Promise.resolve({ data: torusPng });
  throw new Error('No such image');
  });
  });

src/image-loader.ts

@@ -43,7 +43,7 @@ export class ImageStore {
  this.#imageLoader = imageLoader;
  }
 
- async selectImage(selector: ImageSelector): Promise<Image> {
+ selectImage(selector: ImageSelector): Promise<Image> {
  const cacheKey = selector.name;
  return (this.#imageCache[cacheKey] ??= this.loadImage(selector));
  }

src/images/jpeg.test.ts

@@ -7,13 +7,13 @@ import { isJpeg, readJpegInfo } from './jpeg.ts';
 
 describe('jpeg', () => {
  describe('isJpeg', () => {
- it('returns true for JPEG header', async () => {
+ it('returns true for JPEG header', () => {
  const data = new Uint8Array([0xff, 0xd8, 0xff]);
 
  expect(isJpeg(data)).toBe(true);
  });
 
- it('returns false for other data', async () => {
+ it('returns false for other data', () => {
  expect(isJpeg(new Uint8Array())).toBe(false);
  expect(isJpeg(new Uint8Array([1, 2, 3]))).toBe(false);
  });

src/images/png.test.ts

@@ -7,13 +7,13 @@ import { isPng, readPngInfo } from './png.ts';
 
 describe('png', () => {
  describe('isPng', () => {
- it('returns true if PNG header found', async () => {
+ it('returns true if PNG header found', () => {
  const info = isPng(new Uint8Array([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]));
 
  expect(info).toBe(true);
  });
 
- it('returns false for other data', async () => {
+ it('returns false for other data', () => {
  expect(isPng(new Uint8Array())).toBe(false);
  expect(isPng(new Uint8Array([1, 2, 3, 4, 5]))).toBe(false);
  });

src/layout/layout-columns.test.ts

@@ -13,8 +13,8 @@ describe('layout-columns', () => {
 
  beforeEach(() => {
  const fontStore = new FontStore(new FontLoader([]));
- fontStore.selectFont = async () => {
- return fakeFont('Test');
+ fontStore.selectFont = () => {
+ return Promise.resolve(fakeFont('Test'));
  };
  ctx = { fontStore } as MakerCtx;
  box = { x: 20, y: 30, width: 400, height: 700 };

src/layout/layout-image.test.ts

@@ -14,10 +14,10 @@ describe('layout-image', () => {
 
  beforeEach(() => {
  const imageStore = new ImageStore(new ImageLoader([]));
- imageStore.selectImage = vi.fn(async (selector: ImageSelector) => {
+ imageStore.selectImage = vi.fn((selector: ImageSelector) => {
  const match = /^img-(\d+)-(\d+)$/.exec(selector.name);
  if (match) {
- return fakeImage(selector.name, Number(match[1]), Number(match[2]));
+ return Promise.resolve(fakeImage(selector.name, Number(match[1]), Number(match[2])));
  }
  throw new Error(`Unknown image: ${selector.name}`);
  });

src/layout/layout-rows.test.ts

@@ -14,7 +14,7 @@ describe('layout-rows', () => {
 
  beforeEach(() => {
  const fontStore = new FontStore(new FontLoader([]));
- fontStore.selectFont = async () => fakeFont('Test');
+ fontStore.selectFont = () => Promise.resolve(fakeFont('Test'));
  ctx = { fontStore } as MakerCtx;
  box = { x: 20, y: 30, width: 400, height: 700 };
  });

src/layout/layout-text.test.ts

@@ -17,8 +17,8 @@ describe('layout-text', () => {
  defaultFont = fakeFont('Test');
  const italicFont = fakeFont('Test', { style: 'italic' });
  const fontStore = new FontStore(new FontLoader([]));
- fontStore.selectFont = async (selector: FontSelector) => {
- return selector.fontStyle === 'italic' ? italicFont : defaultFont;
+ fontStore.selectFont = (selector: FontSelector) => {
+ return Promise.resolve(selector.fontStyle === 'italic' ? italicFont : defaultFont);
  };
  box = { x: 20, y: 30, width: 400, height: 700 };
  ctx = { fontStore } as MakerCtx;

src/layout/layout.test.ts

@@ -18,7 +18,7 @@ describe('layout', () => {
 
  beforeEach(() => {
  const fontStore = new FontStore(new FontLoader([]));
- fontStore.loadFont = async () => fakeFont('Test');
+ fontStore.loadFont = () => Promise.resolve(fakeFont('Test'));
  ctx = { fontStore } as MakerCtx;
  box = { x: 20, y: 30, width: 400, height: 700 };
  });

src/print-value.test.ts

@@ -27,7 +27,7 @@ describe('print-value', () => {
 
  it('prints functions', () => {
  expect(printValue((x: unknown) => x)).toEqual('anonymous function');
- expect(printValue(async (x: unknown) => x)).toEqual('anonymous function');
+ expect(printValue((x: unknown) => x)).toEqual('anonymous function');
  expect(printValue(printValue)).toEqual('function printValue');
  });
 

src/text.test.ts

@@ -21,8 +21,8 @@ describe('text', () => {
  normalFont = fakeFont('Test');
  const italicFont = fakeFont('Test', { style: 'italic' });
  fontStore = new FontStore(new FontLoader([]));
- fontStore.selectFont = async (selector) => {
- return selector.fontStyle === 'italic' ? italicFont : normalFont;
+ fontStore.selectFont = (selector) => {
+ return Promise.resolve(selector.fontStyle === 'italic' ? italicFont : normalFont);
  };
  });