diff --git a/.cursor/rules/ultracite.mdc b/.cursor/rules/ultracite.mdc index 98495535..392683c8 100644 --- a/.cursor/rules/ultracite.mdc +++ b/.cursor/rules/ultracite.mdc @@ -18,300 +18,56 @@ Ultracite enforces strict type safety, accessibility standards, and consistent c 2. Consider edge cases and error scenarios 3. Follow the rules below strictly 4. Validate accessibility requirements +5. Avoid code duplication ## Rules ### Accessibility (a11y) -- Don't use `accessKey` attribute on any HTML element. -- Don't set `aria-hidden="true"` on focusable elements. -- Don't add ARIA roles, states, and properties to elements that don't support them. -- Don't use distracting elements like `` or ``. -- Only use the `scope` prop on `` elements. -- Don't assign non-interactive ARIA roles to interactive HTML elements. -- Make sure label elements have text content and are associated with an input. -- Don't assign interactive ARIA roles to non-interactive HTML elements. -- Don't assign `tabIndex` to non-interactive HTML elements. -- Don't use positive integers for `tabIndex` property. -- Don't include "image", "picture", or "photo" in img alt prop. -- Don't use explicit role property that's the same as the implicit/default role. -- Make static elements with click handlers use a valid role attribute. -- Always include a `title` element for SVG elements. -- Give all elements requiring alt text meaningful information for screen readers. -- Make sure anchors have content that's accessible to screen readers. -- Assign `tabIndex` to non-interactive HTML elements with `aria-activedescendant`. -- Include all required ARIA attributes for elements with ARIA roles. -- Make sure ARIA properties are valid for the element's supported roles. +- Always include a `title` element for icons unless there's text beside the icon. - Always include a `type` attribute for button elements. -- Make elements with interactive roles and handlers focusable. -- Give heading elements content that's accessible to screen readers (not hidden with `aria-hidden`). -- Always include a `lang` attribute on the html element. -- Always include a `title` attribute for iframe elements. - Accompany `onClick` with at least one of: `onKeyUp`, `onKeyDown`, or `onKeyPress`. - Accompany `onMouseOver`/`onMouseOut` with `onFocus`/`onBlur`. -- Include caption tracks for audio and video elements. -- Use semantic elements instead of role attributes in JSX. -- Make sure all anchors are valid and navigable. -- Ensure all ARIA properties (`aria-*`) are valid. -- Use valid, non-abstract ARIA roles for elements with ARIA roles. -- Use valid ARIA state and property values. -- Use valid values for the `autocomplete` attribute on input elements. -- Use correct ISO language/country codes for the `lang` attribute. ### Code Complexity and Quality -- Don't use consecutive spaces in regular expression literals. -- Don't use the `arguments` object. - Don't use primitive type aliases or misleading types. - Don't use the comma operator. -- Don't use empty type parameters in type aliases and interfaces. -- Don't write functions that exceed a given Cognitive Complexity score. -- Don't nest describe() blocks too deeply in test files. -- Don't use unnecessary boolean casts. -- Don't use unnecessary callbacks with flatMap. - Use for...of statements instead of Array.forEach. -- Don't create classes that only have static members (like a static namespace). -- Don't use this and super in static contexts. -- Don't use unnecessary catch clauses. -- Don't use unnecessary constructors. -- Don't use unnecessary continue statements. -- Don't export empty modules that don't change anything. -- Don't use unnecessary escape sequences in regular expression literals. -- Don't use unnecessary fragments. -- Don't use unnecessary labels. -- Don't use unnecessary nested block statements. -- Don't rename imports, exports, and destructured assignments to the same name. -- Don't use unnecessary string or template literal concatenation. -- Don't use String.raw in template literals when there are no escape sequences. -- Don't use useless case statements in switch statements. -- Don't use ternary operators when simpler alternatives exist. -- Don't use useless `this` aliasing. -- Don't use any or unknown as type constraints. - Don't initialize variables to undefined. -- Don't use the void operators (they're not familiar). -- Use arrow functions instead of function expressions. -- Use Date.now() to get milliseconds since the Unix Epoch. - Use .flatMap() instead of map().flat() when possible. -- Use literal property access instead of computed property access. -- Don't use parseInt() or Number.parseInt() when binary, octal, or hexadecimal literals work. -- Use concise optional chaining instead of chained logical expressions. -- Use regular expression literals instead of the RegExp constructor when possible. -- Don't use number literal object member names that aren't base 10 or use underscore separators. -- Remove redundant terms from logical expressions. -- Use while loops instead of for loops when you don't need initializer and update expressions. -- Don't pass children as props. -- Don't reassign const variables. -- Don't use constant expressions in conditions. -- Don't use `Math.min` and `Math.max` to clamp values when the result is constant. -- Don't return a value from a constructor. -- Don't use empty character classes in regular expression literals. -- Don't use empty destructuring patterns. -- Don't call global object properties as functions. -- Don't declare functions and vars that are accessible outside their block. -- Make sure builtins are correctly instantiated. -- Don't use super() incorrectly inside classes. Also check that super() is called in classes that extend other constructors. -- Don't use variables and function parameters before they're declared. -- Don't use 8 and 9 escape sequences in string literals. -- Don't use literal numbers that lose precision. ### React and JSX Best Practices -- Don't use the return value of React.render. -- Make sure all dependencies are correctly specified in React hooks. -- Make sure all React hooks are called from the top level of component functions. -- Don't forget key props in iterators and collection literals. -- Don't destructure props inside JSX components in Solid projects. +- Don't import `React` itself. - Don't define React components inside other components. -- Don't use event handlers on non-interactive elements. -- Don't assign to React component props. - Don't use both `children` and `dangerouslySetInnerHTML` props on the same element. -- Don't use dangerous JSX props. -- Don't use Array index in keys. - Don't insert comments as text nodes. -- Don't assign JSX properties multiple times. -- Don't add extra closing tags for components without children. - Use `<>...` instead of `...`. -- Watch out for possible "wrong" semicolons inside JSX elements. ### Correctness and Safety - Don't assign a value to itself. -- Don't return a value from a setter. -- Don't compare expressions that modify string case with non-compliant values. -- Don't use lexical declarations in switch clauses. -- Don't use variables that haven't been declared in the document. -- Don't write unreachable code. -- Make sure super() is called exactly once on every code path in a class constructor before this is accessed if the class has a superclass. -- Don't use control flow statements in finally blocks. -- Don't use optional chaining where undefined values aren't allowed. -- Don't have unused function parameters. -- Don't have unused imports. -- Don't have unused labels. -- Don't have unused private class members. -- Don't have unused variables. -- Make sure void (self-closing) elements don't have children. -- Don't return a value from a function with the return type 'void' -- Use isNaN() when checking for NaN. -- Make sure "for" loop update clauses move the counter in the right direction. -- Make sure typeof expressions are compared to valid values. -- Make sure generator functions contain yield. +- Use props instead of parameters in all functions. +- Avoid unused imports and variables. - Don't use await inside loops. -- Don't use bitwise operators. -- Don't use expressions where the operation doesn't change the value. -- Make sure Promise-like statements are handled appropriately. -- Don't use __dirname and __filename in the global scope. -- Prevent import cycles. -- Don't use configured elements. - Don't hardcode sensitive data like API keys and tokens. -- Don't let variable declarations shadow variables from outer scopes. - Don't use the TypeScript directive @ts-ignore. -- Prevent duplicate polyfills from Polyfill.io. -- Don't use useless backreferences in regular expressions that always match empty strings. -- Don't use unnecessary escapes in string literals. -- Don't use useless undefined. -- Make sure getters and setters for the same property are next to each other in class and object definitions. -- Make sure object literals are declared consistently (defaults to explicit definitions). -- Use static Response methods instead of new Response() constructor when possible. -- Make sure switch-case statements are exhaustive. - Make sure the `preconnect` attribute is used when using Google Fonts. -- Use `Array#{indexOf,lastIndexOf}()` instead of `Array#{findIndex,findLastIndex}()` when looking for the index of an item. -- Make sure iterable callbacks return consistent values. -- Use `with { type: "json" }` for JSON module imports. -- Use numeric separators in numeric literals. -- Use object spread instead of `Object.assign()` when constructing new objects. -- Always use the radix argument when using `parseInt()`. -- Make sure JSDoc comment lines start with a single asterisk, except for the first one. -- Include a description parameter for `Symbol()`. -- Don't use spread (`...`) syntax on accumulators. - Don't use the `delete` operator. -- Don't access namespace imports dynamically. -- Don't use namespace imports. -- Declare regex literals at the top level. -- Don't use `target="_blank"` without `rel="noopener"`. ### TypeScript Best Practices - Don't use TypeScript enums. -- Don't export imported variables. -- Don't add type annotations to variables, parameters, and class properties that are initialized with literal expressions. -- Don't use TypeScript namespaces. -- Don't use non-null assertions with the `!` postfix operator. -- Don't use parameter properties in class constructors. -- Don't use user-defined types. -- Use `as const` instead of literal types and type annotations. - Use either `T[]` or `Array` consistently. -- Initialize each enum member value explicitly. -- Use `export type` for types. -- Use `import type` for types. -- Make sure all enum members are literal values. -- Don't use TypeScript const enum. -- Don't declare empty interfaces. -- Don't let variables evolve into any type through reassignments. -- Don't use the any type. -- Don't misuse the non-null assertion operator (!) in TypeScript files. -- Don't use implicit any type on variable declarations. -- Don't merge interfaces and classes unsafely. -- Don't use overload signatures that aren't next to each other. -- Use the namespace keyword instead of the module keyword to declare TypeScript namespaces. +- Don't use the `any` type. ### Style and Consistency - Don't use global `eval()`. -- Don't use callbacks in asynchronous tests and hooks. -- Don't use negation in `if` statements that have `else` clauses. -- Don't use nested ternary expressions. -- Don't reassign function parameters. -- This rule lets you specify global variable names you don't want to use in your application. -- Don't use specified modules when loaded by import or require. -- Don't use constants whose value is the upper-case version of their name. - Use `String.slice()` instead of `String.substr()` and `String.substring()`. -- Don't use template literals if you don't need interpolation or special-character handling. - Don't use `else` blocks when the `if` block breaks early. -- Don't use yoda expressions. -- Don't use Array constructors. -- Use `at()` instead of integer index access. -- Follow curly brace conventions. -- Use `else if` instead of nested `if` statements in `else` clauses. -- Use single `if` statements instead of nested `if` clauses. -- Use `new` for all builtins except `String`, `Number`, and `Boolean`. -- Use consistent accessibility modifiers on class properties and methods. -- Use `const` declarations for variables that are only assigned once. - Put default function parameters and optional function parameters last. -- Include a `default` clause in switch statements. -- Use the `**` operator instead of `Math.pow`. -- Use `for-of` loops when you need the index to extract an item from the iterated array. -- Use `node:assert/strict` over `node:assert`. -- Use the `node:` protocol for Node.js builtin modules. -- Use Number properties instead of global ones. -- Use assignment operator shorthand where possible. -- Use function types instead of object types with call signatures. -- Use template literals over string concatenation. - Use `new` when throwing an error. -- Don't throw non-Error values. - Use `String.trimStart()` and `String.trimEnd()` over `String.trimLeft()` and `String.trimRight()`. -- Use standard constants instead of approximated literals. -- Don't assign values in expressions. -- Don't use async functions as Promise executors. -- Don't reassign exceptions in catch clauses. -- Don't reassign class members. -- Don't compare against -0. -- Don't use labeled statements that aren't loops. -- Don't use void type outside of generic or return types. -- Don't use console. -- Don't use control characters and escape sequences that match control characters in regular expression literals. -- Don't use debugger. -- Don't assign directly to document.cookie. -- Use `===` and `!==`. -- Don't use duplicate case labels. -- Don't use duplicate class members. -- Don't use duplicate conditions in if-else-if chains. -- Don't use two keys with the same name inside objects. -- Don't use duplicate function parameter names. -- Don't have duplicate hooks in describe blocks. -- Don't use empty block statements and static blocks. -- Don't let switch clauses fall through. -- Don't reassign function declarations. -- Don't allow assignments to native objects and read-only global variables. -- Use Number.isFinite instead of global isFinite. -- Use Number.isNaN instead of global isNaN. -- Don't assign to imported bindings. -- Don't use irregular whitespace characters. -- Don't use labels that share a name with a variable. -- Don't use characters made with multiple code points in character class syntax. -- Make sure to use new and constructor properly. -- Don't use shorthand assign when the variable appears on both sides. -- Don't use octal escape sequences in string literals. -- Don't use Object.prototype builtins directly. -- Don't redeclare variables, functions, classes, and types in the same scope. -- Don't have redundant "use strict". -- Don't compare things where both sides are exactly the same. -- Don't let identifiers shadow restricted names. -- Don't use sparse arrays (arrays with holes). -- Don't use template literal placeholder syntax in regular strings. -- Don't use the then property. -- Don't use unsafe negation. -- Don't use var. -- Don't use with statements in non-strict contexts. -- Make sure async functions actually use await. -- Make sure default clauses in switch statements come last. -- Make sure to pass a message value when creating a built-in error. -- Make sure get methods always return a value. -- Use a recommended display strategy with Google Fonts. -- Make sure for-in loops include an if statement. -- Use Array.isArray() instead of instanceof Array. -- Make sure to use the digits argument with Number#toFixed(). -- Make sure to use the "use strict" directive in script files. ### Next.js Specific Rules - Don't use `` elements in Next.js projects. - Don't use `` elements in Next.js projects. -- Don't import next/document outside of pages/_document.jsx in Next.js projects. -- Don't use the next/head module in pages/_document.js on Next.js projects. - -### Testing Best Practices -- Don't use export or module.exports in test files. -- Don't use focused tests. -- Make sure the assertion function, like expect, is placed inside an it() function call. -- Don't use disabled tests. - -## Common Tasks -- `npx ultracite init` - Initialize Ultracite in your project -- `npx ultracite format` - Format and fix code automatically -- `npx ultracite lint` - Check for issues without fixing ## Example: Error Handling ```typescript