Replace ESLint and Prettier with Biome

.github/workflows/ci.yml

@@ -18,32 +18,11 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Cache Yarn cache
-        uses: actions/cache@v4
-        env:
-          cache-name: yarn-cache
-        with:
-          path: ~/.yarn/berry/cache
-          key: ${{ runner.os }}-${{ env.cache-name }}-${{ hashFiles('**/yarn.lock') }}
-          restore-keys: |
-            ${{ runner.os }}-${{ env.cache-name }}
-
-      - name: Use Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '20'
-
-      - name: Enable Corepack
-        run: corepack enable
-
-      - name: Install dependencies
-        run: yarn --immutable
-
-      - name: Build package
-        run: yarn build
+      - name: Setup Biome
+        uses: biomejs/setup-biome@v2
 
       - name: Run tests
-        run: yarn lint
+        run: biome lint
 
   typescript:
     name: Type checking
@@ -88,29 +67,11 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Cache Yarn cache
-        uses: actions/cache@v4
-        env:
-          cache-name: yarn-cache
-        with:
-          path: ~/.yarn/berry/cache
-          key: ${{ runner.os }}-${{ env.cache-name }}-${{ hashFiles('**/yarn.lock') }}
-          restore-keys: |
-            ${{ runner.os }}-${{ env.cache-name }}
-
-      - name: Use Node.js
-        uses: actions/setup-node@v4
-        with:
-          node-version: '20'
-
-      - name: Enable Corepack
-        run: corepack enable
-
-      - name: Install dependencies
-        run: yarn --immutable
+      - name: Setup Biome
+        uses: biomejs/setup-biome@v2
 
       - name: Run formatting
-        run: yarn format
+        run: biome format
 
   unit:
     name: Unit tests

.husky/pre-commit

@@ -1 +1 @@
-yarn lint-staged
+yarn format --staged --no-errors-on-unmatched --write

.vscode/extensions.json

@@ -1,4 +1,4 @@
 {
-  "recommendations": ["dbaeumer.vscode-eslint", "eamodio.gitlens", "esbenp.prettier-vscode"],
+  "recommendations": ["biomejs.biome", "eamodio.gitlens"],
   "unwantedRecommendations": ["dbaeumer.jshint"]
 }

.vscode/settings.json

@@ -1,5 +1,5 @@
 {
-  "editor.defaultFormatter": "esbenp.prettier-vscode",
+  "editor.defaultFormatter": "biomejs.biome",
   "editor.formatOnSave": true,
   "search.exclude": {
     "**/.yarn": true

biome.json

@@ -0,0 +1,43 @@
+{
+  "$schema": "https://biomejs.dev/schemas/1.8.0/schema.json",
+  "files": {
+    "ignore": [".tsimp", "coverage", "dist", ".pnp.cjs", ".pnp.loader.mjs"]
+  },
+  "formatter": {
+    "lineWidth": 100,
+    "indentStyle": "space"
+  },
+  "linter": {
+    "rules": {
+      "complexity": {
+        "noUselessSwitchCase": "off"
+      },
+      "suspicious": {
+        "noConsoleLog": "warn"
+      }
+    }
+  },
+  "javascript": {
+    "formatter": {
+      "quoteStyle": "single"
+    }
+  },
+  "overrides": [
+    {
+      "include": ["**/package.json"],
+      "formatter": {
+        "lineWidth": 1
+      }
+    },
+    {
+      "include": ["**/vite.config.ts"],
+      "linter": {
+        "rules": {
+          "suspicious": {
+            "noConsoleLog": "off"
+          }
+        }
+      }
+    }
+  ]
+}

package.json

@@ -18,12 +18,7 @@
     "unit": "yarn workspaces foreach --all run unit"
   },
   "devDependencies": {
-    "husky": "^9.0.0",
-    "lint-staged": "^15.0.0",
-    "prettier": "^3.2.0"
-  },
-  "resolutions": {
-    "eslint-plugin-import": "npm:eslint-plugin-i@^2.28.0"
+    "husky": "^9.0.0"
   },
   "packageManager": "[email protected]"
 }

packages/react-date-picker/package.json

@@ -85,8 +85,8 @@
     "build-js-cjs-package": "echo '{\n  \"type\": \"commonjs\"\n}' > dist/cjs/package.json",
     "clean": "rimraf dist",
     "copy-styles": "cpy 'src/**/*.css' dist",
-    "format": "prettier --check . --cache",
-    "lint": "eslint . --ext .js,.jsx,.ts,.tsx",
+    "format": "biome format",
+    "lint": "biome lint",
     "prepack": "yarn clean && yarn build",
     "test": "yarn lint && yarn tsc && yarn format && yarn unit",
     "tsc": "tsc",
@@ -115,18 +115,16 @@
     "update-input-width": "^1.4.0"
   },
   "devDependencies": {
+    "@biomejs/biome": "^1.8.0",
     "@testing-library/dom": "^10.0.0",
     "@testing-library/jest-dom": "^6.0.0",
     "@testing-library/react": "^15.0.0",
     "@testing-library/user-event": "^14.5.0",
     "@types/node": "*",
     "@types/react": "*",
     "cpy-cli": "^5.0.0",
-    "eslint": "^8.56.0",
-    "eslint-config-wojtekmaj": "^1.0.0",
     "happy-dom": "^12.6.0",
     "nodemon": "^3.0.0",
-    "prettier": "^3.2.0",
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
     "rimraf": "^3.0.0",

packages/react-date-picker/src/DateInput.spec.tsx

@@ -499,11 +499,11 @@ describe('DateInput', () => {
 
     const { container } = render(<DateInput {...defaultProps} onChange={onChange} value={date} />);
 
-    const customInputs = container.querySelectorAll('input[data-input]');
+    const customInputs = Array.from(container.querySelectorAll('input[data-input]'));
 
-    customInputs.forEach((customInput) => {
+    for (const customInput of customInputs) {
       fireEvent.change(customInput, { target: { value: '' } });
-    });
+    }
 
     expect(onChange).toHaveBeenCalledTimes(1);
     expect(onChange).toHaveBeenCalledWith(null, false);

packages/react-date-picker/src/DateInput.tsx

@@ -54,7 +54,7 @@ function getValue(
 
   const valueDate = toDate(rawValue);
 
-  if (isNaN(valueDate.getTime())) {
+  if (Number.isNaN(valueDate.getTime())) {
     throw new Error(`Invalid date: ${value}`);
   }
 
@@ -143,11 +143,11 @@ function renderCustomInputs(
 
   return placeholder.split(pattern).reduce<React.ReactNode[]>((arr, element, index) => {
     const divider = element && (
-      // eslint-disable-next-line react/no-array-index-key
+      // biome-ignore lint/suspicious/noArrayIndexKey: index is stable here
       <Divider key={`separator_${index}`}>{element}</Divider>
     );
     arr.push(divider);
-    const currentMatch = matches && matches[index];
+    const currentMatch = matches?.[index];
 
     if (currentMatch) {
       const renderFunction =
@@ -240,6 +240,7 @@ export default function DateInput({
     setIsCalendarOpen(isCalendarOpenProps);
   }, [isCalendarOpenProps]);
 
+  // biome-ignore lint/correctness/useExhaustiveDependencies: useEffect intentionally triggered on props change
   useEffect(() => {
     const nextValue = getDetailValueFrom({
       value: valueProps,
@@ -405,7 +406,7 @@ export default function DateInput({
       return;
     }
 
-    const isNumberKey = !isNaN(Number(key));
+    const isNumberKey = !Number.isNaN(Number(key));
 
     if (!isNumberKey) {
       return;
@@ -455,12 +456,10 @@ export default function DateInput({
     ].filter(filterBoolean);
 
     const values: Record<string, number> = {};
-    formElements.forEach((formElement) => {
+    for (const formElement of formElements) {
       values[formElement.name] =
-        'valueAsNumber' in formElement
-          ? formElement.valueAsNumber
-          : Number((formElement as unknown as HTMLInputElement).value);
-    });
+        'valueAsNumber' in formElement ? formElement.valueAsNumber : Number(formElement.value);
+    }
 
     const isEveryValueEmpty = formElements.every((formElement) => !formElement.value);
 
@@ -570,7 +569,6 @@ export default function DateInput({
         key="day"
         {...commonInputProps}
         ariaLabel={dayAriaLabel}
-        // eslint-disable-next-line jsx-a11y/no-autofocus
         autoFocus={index === 0 && autoFocus}
         inputRef={dayInput}
         month={month}
@@ -593,7 +591,6 @@ export default function DateInput({
           key="month"
           {...commonInputProps}
           ariaLabel={monthAriaLabel}
-          // eslint-disable-next-line jsx-a11y/no-autofocus
           autoFocus={index === 0 && autoFocus}
           inputRef={monthSelect}
           locale={locale}
@@ -612,7 +609,6 @@ export default function DateInput({
         key="month"
         {...commonInputProps}
         ariaLabel={monthAriaLabel}
-        // eslint-disable-next-line jsx-a11y/no-autofocus
         autoFocus={index === 0 && autoFocus}
         inputRef={monthInput}
         placeholder={monthPlaceholder}
@@ -629,7 +625,6 @@ export default function DateInput({
         key="year"
         {...commonInputProps}
         ariaLabel={yearAriaLabel}
-        // eslint-disable-next-line jsx-a11y/no-autofocus
         autoFocus={index === 0 && autoFocus}
         inputRef={yearInput}
         placeholder={yearPlaceholder}
@@ -668,7 +663,7 @@ export default function DateInput({
   }
 
   return (
-    // eslint-disable-next-line jsx-a11y/click-events-have-key-events, jsx-a11y/no-static-element-interactions
+    // biome-ignore lint/a11y/useKeyWithClickEvents: This interaction is designed for mouse users only
     <div className={className} onClick={onClick}>
       {renderNativeInput()}
       {renderCustomInputsInternal()}

packages/react-date-picker/src/DateInput/Input.tsx

@@ -2,8 +2,6 @@ import { useEffect, useLayoutEffect } from 'react';
 import clsx from 'clsx';
 import updateInputWidth, { getFontShorthand } from 'update-input-width';
 
-/* eslint-disable jsx-a11y/no-autofocus */
-
 type InputProps = {
   ariaLabel?: string;
   autoFocus?: boolean;
@@ -95,7 +93,7 @@ function getSelectionString(input: HTMLInputElement) {
 
   if ('getSelection' in window) {
     const selection = window.getSelection();
-    return selection && selection.toString();
+    return selection?.toString();
   }
 
   return null;
@@ -172,6 +170,7 @@ export default function Input({
       <input
         aria-label={ariaLabel}
         autoComplete="off"
+        // biome-ignore lint/a11y/noAutofocus: This is up to developers' decision
         autoFocus={autoFocus}
         className={clsx(
           `${className}__input`,