# `@ttsc/lint` ![banner of @ttsc/lint](https://ttsc.dev/og.jpg) [![GitHub license](https://img.shields.io/badge/license-MIT-blue.svg)](https://github.com/samchon/ttsc/blob/master/LICENSE) [![NPM Version](https://img.shields.io/npm/v/@ttsc/lint.svg)](https://www.npmjs.com/package/@ttsc/lint) [![NPM Downloads](https://img.shields.io/npm/dm/@ttsc/lint.svg)](https://www.npmjs.com/package/@ttsc/lint) [![Build Status](https://github.com/samchon/ttsc/workflows/test/badge.svg)](https://github.com/samchon/ttsc/actions?query=workflow%3Atest) [![Guide Documents](https://img.shields.io/badge/Guide-Documents-forestgreen)](https://ttsc.dev/docs) [![Discord Badge](https://img.shields.io/badge/discord-samchon-d91965?style=flat&labelColor=5866f2&logo=discord&logoColor=white&link=https://discord.gg/E94XhzrUCZ)](https://discord.gg/E94XhzrUCZ) A linter and formatter. Co-protagonist of the [`ttsc`](https://ttsc.dev) toolchain, paired with `ttsc`, it replaces `eslint` and covers most of `prettier`. 720+ rules across 21 families. Lint violations surface as `error TSxxxxx` from a single compile pass; the formatter applies via `ttsc format`. ## Demonstration Given this file: ```typescript // src/index.ts var x: number = 3; let y: number = 4; const z: string = 5; console.log(x + y + z); ``` Run `ttsc` with `@ttsc/lint` enabled (see [Setup](#setup)): ```bash $ pnpm ttsc src/index.ts:3:7 - error TS2322: Type 'number' is not assignable to type 'string'. 3 const z: string = 5; ~ src/index.ts:2:5 - error TS17397: [prefer-const] Use const instead of let. 2 let y: number = 4; ~~~~~~~~~~~~~ src/index.ts:1:1 - error TS11966: [no-var] Unexpected var, use let or const instead. 1 var x: number = 3; ~~~~~~~~~~~~~~~~~~ Found 3 errors in the same file, starting at: src/index.ts:3 ``` Type errors (`TS2322`) and lint violations (`TS17397`, `TS11966`) come out together. No second tool, no second CI step. ## Diagnostic code compatibility Every built-in rule has a unique positive numeric code in the reserved `TS9000` through `TS17999` band. These assignments are kept in an append-only ledger: adding a built-in rule does not renumber existing rules, and a removed rule's code is not reused. The LSP surface continues to expose the rule ID, such as `no-var`, in its diagnostic `code` field. The ledger introduction preserved every legacy code that was already unique. For each pre-existing collision group, the alphabetically first rule kept the shared legacy code and every other rule received an available code. Those resolved assignments are now frozen by the same append-only policy. Rules contributed by another Go package share the same collision-free band. Their codes are deterministic for an unchanged complete set of loaded contributors and do not depend on registration order. Adding or removing a contributor recomputes assignments for that complete contributor set and can change contributor codes, but never changes a built-in assignment. The Go host API `RuleCode` also accepts an unregistered name and returns a provisional assignment for the loaded set plus that name. This lookup does not register the name or change the cached codes of loaded contributors; register the rule before using its code as a loaded diagnostic identity. ## Setup ```bash npm install -D ttsc @ttsc/lint typescript ``` Drop a `lint.config.ts` next to your `tsconfig.json`: ```ts // lint.config.ts import type { ITtscLintConfig } from "@ttsc/lint"; export default { format: { printWidth: 100, singleQuote: true, trailingComma: "all", }, rules: { "no-var": "error", "prefer-const": "error", "typescript/no-explicit-any": "error", "typescript/no-floating-promises": "error", }, } satisfies ITtscLintConfig; ``` Run your normal `ttsc` or `ttsx`: ```bash npx ttsc npx ttsx src/index.ts ``` Errors fail the command; warnings print without affecting the exit code. Under `ttsx`, errors stop the program before your entrypoint runs. `ttsc fix` applies every autofix the enabled rules offer, lint and format together. Writes results back to disk, then re-runs type-check + lint. `ttsc format` runs the format rule set through the same dataflow. ```bash npx ttsc fix npx ttsc format ``` `ttsc fix` is a one-shot project pass and rejects `--watch`, single-file mode, and `--emit`. Fixes are written to disk before the recheck runs, so source stays modified even when the command exits non-zero on remaining errors. Recommended flow: run `ttsc fix` locally, commit, then have CI run `ttsc --noEmit` to gate on zero remaining errors. ## Format Configure the formatter through the `format` block in `lint.config.ts`. Keys mirror `.prettierrc`; the presence of the block, even empty `format: {}`, enables the always-on format rules at Prettier defaults so `ttsc format` rewrites your source to match. One boundary to know before you drop `prettier`: no pass normalizes the whitespace between two tokens, so `a=1`, `if(x){`, and `const i : number` are left as written. See [Format → Scope](https://ttsc.dev/docs/lint/format#scope). ```ts // lint.config.ts import type { ITtscLintConfig } from "@ttsc/lint"; export default { format: { printWidth: 100, singleQuote: true, trailingComma: "all", sortImports: { order: ["", "", "", "", "^[./]"], unsafeSortRuntimeImports: true, // accepts module evaluation reordering }, jsDoc: true, }, rules: { "no-var": "error" }, } satisfies ITtscLintConfig; ``` `ttsc check` does **not** fail on formatting by default. It surfaces format diagnostics only when you opt in with `format.severity`. `ttsc format` runs the active format rules across the project and writes results to disk regardless of `severity`. Each `format` key controls one behavior: | Config key | Effect | | --- | --- | | `severity` (default `"off"`) | Check-time diagnostic level for formatting. Does not gate `ttsc format`. | | `semi` | Insert trailing semicolons on ASI-terminated statements, and own the member separator in interface, type-literal, mapped-type, and class bodies. | | `singleQuote` | Convert quoted strings to the preferred quote style. | | `arrowParens` | Add or remove parens around a single arrow parameter. | | `bracketSpacing` | Spaces inside object and named-import/export braces. | | `quoteProps` | Quote or unquote object property keys. | | `trailingComma` | Add trailing commas to multi-line lists. | | `printWidth`, `tabWidth`, `useTabs`, `endOfLine` | Column-aware line reflow. Object/array literals, call/new arguments, and named import/export clauses break across lines when their flat form overflows the budget. | | `sortImports` (opt-in) | Sort named specifiers and erased type-only imports. Runtime declaration sorting requires `unsafeSortRuntimeImports`. | | `jsDoc` (on by default) | Normalize JSDoc blocks toward [prettier-plugin-jsdoc](https://github.com/hosseinmd/prettier-plugin-jsdoc). | `sortImports` is **opt-in** — it takes effect only when you set it. Every other key takes effect as soon as the `format` block is present (JSDoc normalization included; set `jsDoc: false` to opt out), which also applies several keyless layout behaviors (statement splitting, indentation, whitespace normalization, clause joining, continuation-keyword placement, declaration-header reflow, ternary-nullish parens, leading-semicolon merging, and parameter-property breaking). The safe default preserves the source order of every runtime-bearing import, including default, namespace, named, and bare imports, because each form can evaluate its dependency module. It still alphabetizes named specifiers within one declaration and can sort or merge a block made entirely of erased `import type` declarations. Set `unsafeSortRuntimeImports: true` only when every dependency in the block is order-independent. `combineTypeAndValue` affects a mixed type/value block only under that unsafe opt-in. Formatting is configured **only** through the `format` block. The `rules` map is for lint rules; a `format/*` id placed there is ignored. To turn a format behavior off, set its `format` key (for example `trailingComma: "none"`), not a `rules` entry. ## Rules Lint rules are off until you enable them in `lint.config.ts`. Severity values: `"error"` fails the build, `"warning"` prints without affecting the exit code, `"off"` disables the rule. ```ts // lint.config.ts export default { rules: { "no-var": "error", "eqeqeq": "error", "prefer-template": "warning", "typescript/no-non-null-assertion": "off", }, } satisfies ITtscLintConfig; ``` Rules with options use an ESLint-style tuple such as `["error", { allowElseIf: false }]`. A built-in rule whose typed setting is severity-only accepts no payload, even while it is `"off"`; the engine reports an invalid configuration instead of silently discarding the extra value. Rule IDs use ESLint-style kebab-case and slash namespaces, `no-var`, `react/jsx-key`, `testing-library/prefer-screen-queries`. The exported `ITtscLintRules` type is the intersection of family-specific interfaces such as `ITtscLintCoreRules`, `ITtscLintTypeScriptRules`, `ITtscLintReactRules`, and `ITtscLintVitestRules`, so users can type a whole config or a narrower family-shaped object. Each rule below links to its TypeScript fixture under [`packages/lint/test/testdata/corpus/`](https://github.com/samchon/ttsc/tree/master/packages/lint/test/testdata/corpus). ### ESLint core Generic ESLint-compatible rules that apply to both JavaScript and TypeScript source. Every rule listed here corresponds 1-to-1 with an ESLint core rule of the same kebab-case id, so projects migrating from ESLint can paste their rule severities into `lint.config.ts` without renaming anything. TypeScript-only rules and `@typescript-eslint` extensions live under `typescript/*` in [TypeScript](#typescript), `@ttsc/lint` does not accept legacy bare names or `@typescript-eslint/*` aliases for those. Source: [ESLint core rules](https://eslint.org/docs/latest/rules/). - [`camelcase`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/camelcase.ts): reject identifier declarations that aren't camelCase or PascalCase, snake_case bindings are flagged. - [`complexity`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/complexity.ts): reject function bodies whose cyclomatic complexity exceeds twenty (default ESLint threshold). - [`consistent-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/consistent-return.ts): reject functions where some `return` statements return a value and others fall through without one. - [`curly`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/curly.ts): require block statements for every `if`, `else`, `while`, `for`, and `do` body. Reject the single-statement shorthand. - [`default-case`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/default-case.ts): require `switch` statements to include a `default` clause. - [`default-case-last`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/default-case-last.ts): require the `default` clause of a `switch` statement to appear last. - [`default-param-last`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/default-param-last.ts): keeps parameters with default values at the end of the list. - [`dot-notation`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/dot-notation.ts): prefers dot property access when a string-literal key is a valid identifier. - [`eqeqeq`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/eqeqeq.ts): requires strict equality operators. - [`for-direction`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/for-direction.ts): catches loop counters updated in the wrong direction. - [`getter-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/getter-return.ts): require a `get` accessor's body to return a value on every reachable exit. - [`grouped-accessor-pairs`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/grouped-accessor-pairs.ts): require the `get` and `set` accessors of a property to be declared adjacent in the class body. - [`guard-for-in`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/guard-for-in.ts): require a `for...in` body to be wrapped in an `if` statement (or to skip iterations with a leading `if (...) continue`) so inherited keys are guarded, matching ESLint core's structural check. - [`id-length`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/id-length.ts): reject identifier names shorter than two characters. - [`init-declarations`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/init-declarations.ts): require every `var` / `let` declaration to be initialized at its declaration site. - [`max-classes-per-file`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-classes-per-file.ts): reject a source file that declares more than one class. - [`max-depth`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-depth.ts): reject block-statement nesting deeper than four levels inside a function. - [`max-lines`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-lines.ts): reject a source file whose total line count exceeds three hundred. - [`max-lines-per-function`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-lines-per-function.ts): reject a function whose body spans more than fifty lines. - [`max-nested-callbacks`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-nested-callbacks.ts): reject callback nesting deeper than ten inside a single function. - [`max-params`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-params.ts): reject function declarations with more than three parameters. - [`max-statements`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/max-statements.ts): reject function bodies whose statement count exceeds ten. - [`no-alert`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-alert.ts): rejects `alert`, `confirm`, and `prompt`. - [`no-array-constructor`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-array-constructor.ts): rejects `Array` constructor calls. - [`no-async-promise-executor`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-async-promise-executor.ts): rejects async Promise executors. - [`no-await-in-loop`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-await-in-loop.ts): reject explicit and implicit awaits evaluated in repeated loop positions. - [`no-bitwise`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-bitwise.ts): rejects bitwise operators. - [`no-caller`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-caller.ts): rejects `arguments.caller` and `arguments.callee`. - [`no-case-declarations`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-case-declarations.ts): rejects lexical declarations directly inside `case` clauses. - [`no-class-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-class-assign.ts): rejects reassignment of class declarations. - [`no-compare-neg-zero`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-compare-neg-zero.ts): rejects comparisons against `-0`. - [`no-cond-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-cond-assign.ts): rejects assignments inside conditions. - [`no-console`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-console.ts): rejects `console` calls. - [`no-constant-condition`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-constant-condition.ts): rejects constant conditions. - [`no-constructor-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-constructor-return.ts): reject `return X;` (with a value) inside a class constructor. - [`no-continue`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-continue.ts): rejects `continue` statements. - [`no-control-regex`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-control-regex.ts): rejects control characters in regular expressions. - [`no-debugger`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-debugger.ts): rejects `debugger` statements. - [`no-delete-var`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-delete-var.ts): rejects deleting variables. - [`no-dupe-args`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-dupe-args.ts): rejects duplicate function parameters. - [`no-dupe-class-members`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-dupe-class-members.ts): reject two declarations of the same member on a single class. - [`no-dupe-else-if`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-dupe-else-if.ts): rejects duplicate or logically covered `else if` conditions. - [`no-dupe-keys`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-dupe-keys.ts): rejects duplicate object keys. - [`no-duplicate-case`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-duplicate-case.ts): rejects duplicate `switch` case labels. - [`no-duplicate-imports`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-duplicate-imports.ts): reject a repeated module specifier when the import declarations could be merged into one; `allowSeparateTypeImports` and `includeExports` match the ESLint options. - [`no-else-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-else-return.ts): reject an `else` block whose preceding `if` branch returns on every path. - [`no-empty`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty.ts): rejects uncommented empty blocks and switches; `allowEmptyCatch` accepts empty catches. - [`no-empty-character-class`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-character-class.ts): rejects empty regex character classes. - [`no-empty-function`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-function.ts): rejects uncommented empty functions unless their category is allowed. - [`no-empty-named-blocks`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-named-blocks.ts): rejects empty named import/export clauses (`import {} from "x"`, `export {}`). - [`no-empty-pattern`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-pattern.ts): rejects empty destructuring patterns. - [`no-empty-static-block`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-static-block.ts): rejects uncommented empty class static blocks. - [`no-eq-null`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-eq-null.ts): rejects loose null comparisons. - [`no-eval`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-eval.ts): rejects `eval`. - [`no-ex-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-ex-assign.ts): rejects reassignment of caught exceptions. - [`no-extend-native`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-extend-native.ts): reject assignments to a built-in prototype such as `Array.prototype.foo = bar`. - [`no-extra-bind`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-extra-bind.ts): rejects `.bind(thisArg)` on arrows and regular functions that never read their own `this`, while preserving partial application. - [`no-extra-boolean-cast`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-extra-boolean-cast.ts): rejects redundant boolean casts. - [`no-fallthrough`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-fallthrough.ts): rejects `switch` cases whose end is reachable and that lack an intentional `// falls through` comment before the next label. - [`no-func-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-func-assign.ts): rejects reassignment of function declarations. - [`no-implicit-coercion`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-implicit-coercion.ts): prefer named conversions to `!!x`, `+x`, and empty-string concatenation; authors check BigInt acceptance and primitive hints. - [`no-import-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-import-assign.ts): resolves imported bindings through the checker and rejects assignments, destructuring and loop writes, plus direct namespace mutations such as `ns.x = ...` and `Object.assign(ns, value)`. - [`no-inner-declarations`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-inner-declarations.ts): rejects block functions with legacy sloppy semantics; `"both"` also checks nested `var` declarations. - [`no-invalid-this`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-invalid-this.ts): reject `this` references outside any function-like, class method, or class-static-block context. - [`no-irregular-whitespace`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-irregular-whitespace.ts): rejects irregular whitespace. - [`no-iterator`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-iterator.ts): rejects `__iterator__`. - [`no-labels`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-labels.ts): rejects labels. - [`no-lone-blocks`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-lone-blocks.ts): rejects unnecessary standalone blocks. - [`no-lonely-if`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-lonely-if.ts): rejects `if` as the only statement in an `else`. - [`no-loop-func`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-loop-func.ts): reject loop-created closures only when they capture bindings that can change between iterations. - [`no-loss-of-precision`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-loss-of-precision.ts): rejects number literals that lose precision. - [`no-magic-numbers`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-magic-numbers.ts): reject inline numeric literals outside `const` initializer position. `0`, `1`, `-1`, array indices, and enum values are exempt. - [`no-misleading-character-class`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-misleading-character-class.ts): rejects misleading regex character classes. - [`no-mixed-operators`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-mixed-operators.ts): reject mixing operators of different precedence families in the same expression without explicit parentheses around the inner sub-expression. - [`no-multi-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-multi-assign.ts): rejects chained assignments. - [`no-multi-str`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-multi-str.ts): rejects multiline string escapes. - [`no-negated-condition`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-negated-condition.ts): rejects negated conditions with an `else`. - [`no-nested-ternary`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-nested-ternary.ts): rejects nested ternary expressions. - [`no-new`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-new.ts): rejects `new` expressions used only for side effects. - [`no-new-func`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-new-func.ts): rejects `Function` constructors. - [`no-new-symbol`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-new-symbol.ts): reject `new Symbol(...)`. - [`no-new-wrappers`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-new-wrappers.ts): rejects primitive wrapper constructors. - [`no-obj-calls`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-obj-calls.ts): rejects calling global objects as functions. - [`no-object-constructor`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-object-constructor.ts): rejects `new Object()`. - [`no-octal`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-octal.ts): rejects legacy octal literals. - [`no-octal-escape`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-octal-escape.ts): rejects octal escape sequences. - [`no-param-reassign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-param-reassign.ts): rejects writes to parameter bindings, with `props` and property-ignore options matching ESLint. - [`no-plusplus`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-plusplus.ts): rejects `++` and `--`. - [`no-promise-executor-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-promise-executor-return.ts): rejects values returned by global Promise executors, with an `allowVoid` option for explicit unary `void` returns. - [`no-proto`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-proto.ts): rejects `__proto__`. - [`no-prototype-builtins`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-prototype-builtins.ts): rejects direct `Object.prototype` method calls. - [`no-redeclare`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-redeclare.ts): rejects redeclaring a binding in the same scope. - [`no-regex-spaces`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-regex-spaces.ts): rejects repeated literal spaces in regexes. - [`no-restricted-imports`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-restricted-imports.ts): reject static imports and re-exports selected by user-configured exact paths, gitignore-style groups, or regular expressions. - [`no-restricted-syntax`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-restricted-syntax.ts): reject only syntax matching the project's configured TypeScript-Go AST selectors; no selectors means no restrictions. - [`no-return-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-return-assign.ts): rejects assignments in `return`. - [`no-script-url`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-script-url.ts): rejects `javascript:` URLs. - [`no-self-assign`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-self-assign.ts): rejects assignments to the same value. - [`no-self-compare`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-self-compare.ts): rejects comparing a value to itself. - [`no-sequences`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-sequences.ts): rejects comma expressions. - [`no-setter-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-setter-return.ts): rejects returned values from setters. - [`no-shadow`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-shadow.ts): reject a nested-scope binding that shadows a same-name binding from an outer scope. - [`no-shadow-restricted-names`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-shadow-restricted-names.ts): rejects shadowing restricted globals. - [`no-sparse-arrays`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-sparse-arrays.ts): rejects sparse arrays. - [`no-template-curly-in-string`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-template-curly-in-string.ts): rejects `${...}` text inside normal strings. - [`no-this-before-super`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-this-before-super.ts): reject `this` (or `super.x`) references that precede the first `super()` call in a derived constructor. - [`no-throw-literal`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-throw-literal.ts): rejects throwing literals. - [`no-undef-init`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-undef-init.ts): rejects initializing to `undefined`. - [`no-undefined`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-undefined.ts): rejects the global `undefined` identifier. - [`no-unneeded-ternary`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unneeded-ternary.ts): rejects redundant ternary expressions. - [`no-unreachable`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unreachable.ts): reject statements that follow an unconditional `return`, `throw`, `break`, or `continue` in the same block, control flow has already left the block, so any later statement is dead code. - [`no-unsafe-finally`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unsafe-finally.ts): rejects control flow from `finally`. - [`no-unsafe-negation`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unsafe-negation.ts): rejects unsafe negation before relational checks. - [`no-unsafe-optional-chaining`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unsafe-optional-chaining.ts): reject member access or call expressions that chain off an optional chain without continuing the chain. - [`no-unused-expressions`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unused-expressions.ts): rejects expression statements with no effect under ESLint's default semantics, accepting directive prologues (arbitrary text, determined by AST position) and productive expressions such as `void promise()` while rejecting tagged templates and misplaced strings; the upstream options are supported. - [`no-unused-labels`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unused-labels.ts): rejects labels that no `break` or `continue` targets. - [`no-useless-assignment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-assignment.ts): reject an assignment whose value is immediately overwritten by the very next statement without an intervening read of the same identifier. - [`no-useless-call`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-call.ts): rejects unnecessary `.call()` and `.apply()`. - [`no-useless-catch`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-catch.ts): rejects catch blocks that only rethrow. - [`no-useless-computed-key`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-computed-key.ts): rejects unnecessary computed property keys. - [`no-useless-concat`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-concat.ts): rejects unnecessary string concatenation. - [`no-useless-constructor`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-constructor.ts): reject empty base constructors and exact single-rest super forwarding; zero or fixed-prefix derived calls filter caller arguments and remain meaningful. - [`no-useless-escape`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-escape.ts): rejects backslash escapes that have no effect inside strings or regexes. - [`no-useless-rename`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-rename.ts): rejects import/export/destructure renames to the same name. - [`no-useless-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-return.ts): reject a bare `return;` whose only effect is to end a function body that would have returned anyway. - [`no-var`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-var.ts): rejects `var`. - [`no-with`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-with.ts): rejects `with` statements. - [`object-shorthand`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/object-shorthand.ts): requires object property shorthand where possible. - [`operator-assignment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/operator-assignment.ts): prefers compound assignment operators. - [`prefer-arrow-callback`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-arrow-callback.ts): reject `function() { ... }` expressions passed as callback arguments. Prefer the arrow form. - [`prefer-const`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-const.ts): prefers `const` for lexical `let` bindings that are never reassigned, including declaration-only and destructured bindings with ESLint-compatible options. - [`prefer-destructuring`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-destructuring.ts): reject single-property and single-index variable declarations (`const a = obj.a`, `const x = arr[0]`) that destructuring would replace verbatim. - [`prefer-exponentiation-operator`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-exponentiation-operator.ts): prefers `**` over `Math.pow`. - [`prefer-for-of`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-for-of.ts): prefers `for...of` for simple array iteration. - [`prefer-named-capture-group`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-named-capture-group.ts): reject regex literals with unnamed capturing groups `(...)`. Prefer named groups `(?...)`. - [`prefer-numeric-literals`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-numeric-literals.ts): prefer ES2015+ numeric literal forms (`0b…`, `0o…`, `0x…`) over `parseInt(string, 2 | 8 | 16)`. - [`prefer-object-has-own`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-object-has-own.ts): prefer `Object.hasOwn(obj, key)` over `Object.prototype.hasOwnProperty.call(obj, key)`. - [`prefer-object-spread`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-object-spread.ts): prefer object-spread `{ ...a, ...b }` over `Object.assign({}, a, b)`. - [`prefer-rest-params`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-rest-params.ts): reject reading from `arguments` in a non-arrow function body. Prefer the ES2015 rest-parameter form `(...args)`. - [`prefer-spread`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-spread.ts): prefers spread arguments over `.apply`. - [`prefer-template`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-template.ts): prefers template literals over string concatenation. - [`radix`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/radix.ts): requires a radix argument for `parseInt`. - [`require-yield`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/require-yield.ts): requires generator functions to contain `yield`. - [`sort-imports`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/sort-imports.ts): reject import specifiers within a single `import` declaration that aren't alphabetically sorted. - [`sort-keys`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/sort-keys.ts): reject object-literal property keys that aren't alphabetically sorted. - [`use-isnan`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/use-isnan.ts): requires `Number.isNaN`/`isNaN` for `NaN` checks. - [`valid-typeof`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/valid-typeof.ts): restricts `typeof` comparisons to valid strings. - [`vars-on-top`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/vars-on-top.ts): requires `var` declarations at the top of their scope. - [`yoda`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/yoda.ts): rejects literal-first comparisons. ### TypeScript TypeScript-only rules and `@typescript-eslint` plugin equivalents, exposed under the `typescript/*` namespace. Each rule either requires TypeScript syntax (interface, `enum`, `namespace`, `as`, `!`, `import type`, type parameters, declaration merging, parameter properties, triple-slash references) or originates from `@typescript-eslint` as a TS-aware extension that has no counterpart in plain ESLint. Source: [`typescript-eslint`](https://github.com/typescript-eslint/typescript-eslint). - [`typescript/adjacent-overload-signatures`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/adjacent-overload-signatures.ts): keeps overload declarations for the same member adjacent. - [`typescript/array-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/array-type.ts): prefers `T[]` and `readonly T[]` over array helper types. - [`typescript/await-thenable`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/await-thenable.ts): rejects `await` on a value that is neither a Promise nor a thenable, non-awaitable members passed to native Promise aggregators, `for await...of` over a value that is not async iterable, and `await using` of a resource that is not async disposable (type-aware). - [`typescript/ban-ts-comment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/ban-ts-comment.ts): rejects `@ts-ignore` and `@ts-nocheck`, and requires a description after `@ts-expect-error` (upstream recommended defaults; each directive configurable via `boolean`, `"allow-with-description"`, or `{ descriptionFormat }`). - [`typescript/ban-tslint-comment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/ban-tslint-comment.ts): rejects obsolete `tslint:` comments. - [`typescript/class-literal-property-style`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-class-literal-property-style.ts): prefer a `static readonly` field over a `get` accessor whose body is a single `return ;`. - [`typescript/consistent-generic-constructors`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-consistent-generic-constructors.ts): reject the redundant pattern where a variable is annotated with a generic type AND the same generic arguments are repeated on the constructor: `const m: Map = new Map()`. - [`typescript/consistent-indexed-object-style`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/consistent-indexed-object-style.ts): prefers `Record` for single index-signature object types. - [`typescript/consistent-type-assertions`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/consistent-type-assertions.ts): prefers `as` type assertions over angle-bracket assertions. - [`typescript/consistent-type-definitions`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/consistent-type-definitions.ts): prefers interfaces for object-shaped type definitions. - [`typescript/consistent-type-exports`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-consistent-type-exports.ts): require type-only re-exports to use `export type { ... }` instead of mixing them with value-level re-exports. - [`typescript/consistent-type-imports`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/consistent-type-imports/violation.ts): uses `import type` when imported names are type-only. - [`typescript/explicit-function-return-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-explicit-function-return-type.ts): require every exported function and method declaration to carry an explicit return-type annotation. - [`typescript/explicit-member-accessibility`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-explicit-member-accessibility.ts): require an explicit accessibility modifier (`public`, `private`, or `protected`) on every class member declaration. - [`typescript/method-signature-style`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/method-signature-style.ts): prefers function-property signatures over method shorthand signatures. - [`typescript/no-array-delete`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-array-delete.ts): rejects `delete` on array elements. - [`typescript/no-array-for-each`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-array-for-each.ts): prefer `for ... of` over `Array.prototype.forEach()`. - [`typescript/no-base-to-string`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-base-to-string.ts): rejects string coercion of values whose `toString` resolves to the default `Object.prototype.toString` (type-aware). - [`typescript/no-confusing-non-null-assertion`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-confusing-non-null-assertion.ts): rejects confusing non-null assertions next to equality checks. - [`typescript/no-confusing-void-expression`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-confusing-void-expression.ts): reject `void X` expressions used in any position where the surrounding context expects a value, initializer, call argument, `return` operand, conditional, binary, or ternary subexpression. - [`typescript/no-deprecated`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-deprecated.ts): reject references to declarations annotated `@deprecated` in their JSDoc, with the deprecation comment surfaced at the reference site (type-aware). - [`typescript/no-duplicate-enum-values`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-duplicate-enum-values.ts): rejects duplicate enum member values. - [`typescript/no-dynamic-delete`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-dynamic-delete.ts): rejects `delete` on dynamically computed property keys. - [`typescript/no-empty-interface`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-interface.ts): rejects empty interfaces. - [`typescript/no-empty-object-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-empty-object-type.ts): rejects empty object type literals. - [`typescript/no-explicit-any`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-explicit-any.ts): rejects explicit `any`. - [`typescript/no-extra-non-null-assertion`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-extra-non-null-assertion.ts): rejects repeated non-null assertions. - [`typescript/no-extraneous-class`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-extraneous-class.ts): reject classes that exist purely as a namespace for static members or that are entirely empty. - [`typescript/no-floating-promises`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-floating-promises.ts): rejects discarded built-in Promises, invalid rejection-handler chains, and Promise-bearing arrays; structural thenables, `void`, async IIFEs, and known-safe calls/types follow the rule's typed options. - [`typescript/no-for-in-array`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-for-in-array.ts): reject `for (const k in arr)` where `arr` is statically typed as an array or tuple. - [`typescript/no-import-type-side-effects`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-import-type-side-effects/violation.ts): hoists inline `type` modifiers into a single `import type` declaration. - [`typescript/no-inferrable-types`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-inferrable-types.ts): rejects type annotations TypeScript can infer. - [`typescript/no-invalid-void-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-invalid-void-type.ts): reject `void` used as anything other than a function return type. - [`typescript/no-magic-numbers`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-magic-numbers.ts): typeScript-aware extension of `no-magic-numbers` that additionally ignores enum member values. - [`typescript/no-meaningless-void-operator`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-meaningless-void-operator.ts): reject `void X` where `X` is already statically typed `void`, the operator adds nothing because the operand already evaluates to `undefined` (type-aware). - [`typescript/no-misused-new`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-misused-new.ts): rejects constructor-like signatures in interfaces. - [`typescript/no-misused-promises`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-misused-promises.ts): reject thenables in boolean, spread, synchronous-disposal, and void-return contexts using resolved types. - [`typescript/no-misused-spread`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-misused-spread.ts): reject spread expressions whose operand is syntactically wrong for the surrounding context. - [`typescript/no-mixed-enums`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-mixed-enums.ts): rejects enums that mix numeric and string members. - [`typescript/no-namespace`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-namespace.ts): rejects non-ambient namespaces. - [`typescript/no-non-null-asserted-nullish-coalescing`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-non-null-asserted-nullish-coalescing.ts): rejects non-null assertions next to `??`. - [`typescript/no-non-null-asserted-optional-chain`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-non-null-asserted-optional-chain.ts): rejects non-null assertions on optional chains. - [`typescript/no-non-null-assertion`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-non-null-assertion.ts): rejects postfix non-null assertions. - [`typescript/no-redundant-type-constituents`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-redundant-type-constituents.ts): reject union and intersection type constituents that the type system absorbs anyway, `string | any` collapses to `any`, `T & never` collapses to `never`, `T & unknown` collapses to `T`, and repeated constituents add nothing. - [`typescript/no-require-imports`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-require-imports.ts): rejects CommonJS `require` imports. - [`typescript/no-restricted-types`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-restricted-types.ts): reject exact type spellings from the configured `types` map, with custom messages, automatic replacements, and editor suggestions; no options is a no-op. - [`typescript/no-this-alias`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-this-alias.ts): rejects aliasing `this` to locals. - [`typescript/no-unnecessary-boolean-literal-compare`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unnecessary-boolean-literal-compare.ts): reject direct comparison of a boolean-typed value with `true` / `false` literals, `x === true` is just `x`, `x !== false` is just `x`. - [`typescript/no-unnecessary-condition`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unnecessary-condition.ts): reject conditions whose static type proves the runtime truthiness is fixed, `if ({})`, `if (null)`, `while ("")`, `0 && f()` (type-aware). - [`typescript/no-unnecessary-parameter-property-assignment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unnecessary-parameter-property-assignment.ts): rejects constructor assignments already handled by parameter properties. - [`typescript/no-unnecessary-qualifier`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unnecessary-qualifier.ts): reject namespace/enum qualifiers that the surrounding scope makes unnecessary (type-aware). - [`typescript/no-unnecessary-template-expression`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unnecessary-template-expression.ts): reject template literals that collapse to a regular string, `` `${"abc"}` ``, `` `${name}` `` around a string-typed value, or a plain `` `abc` `` with no escaped backticks (type-aware). - [`typescript/no-unnecessary-type-arguments`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unnecessary-type-arguments.ts): reject `Foo` calls where the supplied generic argument is the same as the parameter's default, the argument adds nothing (type-aware). - [`typescript/no-unnecessary-type-assertion`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unnecessary-type-assertion.ts): reject `x as T`, `x`, and `x!` assertions whose target type is the same as `x`'s already-known static type, the assertion adds nothing (type-aware). - [`typescript/no-unnecessary-type-constraint`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unnecessary-type-constraint.ts): rejects redundant `extends any` and `extends unknown` constraints; its fix preserves the `` disambiguation required by single-parameter generic arrows in TSX, MTS, and CTS files. - [`typescript/no-unsafe-argument`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-argument.ts): reject passing an `any`-typed value to a parameter whose declared type is concrete (type-aware). - [`typescript/no-unsafe-assignment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-assignment.ts): reject direct and recursively nested `any` values escaping through annotated or inferred variables, reassignments, defaults, class members, contextual properties, spreads, and destructuring; `unknown` receivers remain allowed (type-aware, no options). - [`typescript/no-unsafe-call`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-call.ts): reject calling a value whose static type is `any` (type-aware). - [`typescript/no-unsafe-declaration-merging`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unsafe-declaration-merging.ts): rejects unsafe class/interface declaration merging. - [`typescript/no-unsafe-enum-comparison`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-enum-comparison.ts): reject `==` / `===` / `!=` / `!==` comparisons between an enum-typed value and a plain `number` or `string` of the same widened primitive, the comparison silently accepts unrelated enums and raw literals that happen to share the underlying primitive (type-aware). - [`typescript/no-unsafe-function-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-unsafe-function-type.ts): rejects the unsafe `Function` type. - [`typescript/no-unsafe-member-access`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-member-access.ts): reject member access on a value whose static type is `any` (type-aware). - [`typescript/no-unsafe-return`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-return.ts): reject a `return` expression whose static type is `any` from a function whose declared return type is a concrete (non-`any` / non-`unknown` / non-`void`) shape, the `any` leaks past the type boundary and disables every downstream check on the returned value (type-aware). - [`typescript/no-unsafe-unary-minus`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-unsafe-unary-minus.ts): reject the unary `-` operator applied to an operand whose static type is not number-like or bigint-like, `-x` silently coerces strings, objects, and other shapes via `Number(x)` and almost always indicates a bug (type-aware). - [`typescript/no-useless-constructor`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-no-useless-constructor.ts): typeScript-aware extension of `no-useless-constructor` that tolerates a constructor existing solely to expose parameter properties. - [`typescript/no-useless-empty-export`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-useless-empty-export.ts): rejects redundant empty `export {}` declarations in module files. - [`typescript/no-wrapper-object-types`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/no-wrapper-object-types.ts): rejects boxed object type names such as `String` and `Boolean`. - [`typescript/non-nullable-type-assertion-style`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/non-nullable-type-assertion-style.ts): reject `x as Foo` assertions whose target type is the non-nullable version of `x`'s static type. Replace with the shorter `x!` non-null assertion. - [`typescript/only-throw-error`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/only-throw-error.ts): reject `throw X` where `X` is statically known not to derive from `Error`, string literals, numbers, plain object literals, and the like. - [`typescript/parameter-properties`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-parameter-properties.ts): reject TypeScript parameter-property constructors (`constructor(public foo: T)`). Prefer plain field declarations so the class shape is visible from the member list instead of buried inside the constructor parameter list. - [`typescript/prefer-as-const`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-as-const.ts): prefers `as const` over literal type assertions and matching literal type annotations on variables and class properties. - [`typescript/prefer-enum-initializers`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-enum-initializers.ts): requires explicit enum member initializers. - [`typescript/prefer-find`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-find.ts): prefer `array.find(predicate)` over `array.filter(predicate)[0]` / `.shift()` when only the first match is needed. - [`typescript/prefer-function-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-function-type.ts): prefers function type aliases over single-call interfaces. - [`typescript/prefer-includes`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-includes.ts): prefer `array.includes(x)` over `array.indexOf(x) !== -1` (and the matching `=== -1`, `>= 0`, `< 0`, `> -1` shapes) on array, tuple, and string receivers (type-aware). - [`typescript/prefer-literal-enum-member`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-literal-enum-member.ts): prefers literal enum member initializers over computed expressions. - [`typescript/prefer-namespace-keyword`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/prefer-namespace-keyword.ts): prefers `namespace` over TypeScript's legacy `module` keyword. - [`typescript/prefer-nullish-coalescing`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-nullish-coalescing.ts): prefer `??` over `||` (and `??=` over `||=`, and `??` over the ternary `x ? x : y`) when the intent is to default `null` / `undefined`. - [`typescript/prefer-optional-chain`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-optional-chain.ts): prefer an optional chain (`a?.b?.c`) over chained boolean guards such as `a && a.b && a.b.c` or `a != null && a.b`. - [`typescript/prefer-promise-reject-errors`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-promise-reject-errors.ts): reject `Promise.reject(value)` where `value` is statically known not to derive from `Error`, type-aware analog of `only-throw-error` for the rejection side of the promise contract. - [`typescript/prefer-readonly`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-readonly.ts): consider readonly for initialized private fields with no resolved source-file reassignment (type-aware); aliases, computed keys and destructuring are tracked, while deep object mutation does not replace the field and dynamic or reflective mutation remains a limitation. - [`typescript/prefer-reduce-type-parameter`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-reduce-type-parameter.ts): prefer `arr.reduce(..., initial)` over `arr.reduce(..., initial as T)` so the accumulator type is set on the call site instead of widened away inside the assertion (type-aware). - [`typescript/prefer-regexp-exec`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-regexp-exec.ts): prefer `regex.exec(str)` over `str.match(regex)` when the regex carries the `g` flag, `.match` returns only the matched substrings and discards capture groups. - [`typescript/prefer-return-this-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-return-this-type.ts): prefer the polymorphic this return type only when every normal completion returns this, without bare return or fallthrough; nested function returns are excluded. - [`typescript/prefer-string-starts-ends-with`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-prefer-string-starts-ends-with.ts): prefer `str.startsWith(p)` / `str.endsWith(p)` over `str.indexOf(p) === 0`, `str.indexOf(p, str.length - p.length) !== -1`, `str.lastIndexOf(p) === str.length - p.length`, and the anchored-regex `/^p/.test(str)` / `/p$/.test(str)` idioms (type-aware). - [`typescript/promise-function-async`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-promise-function-async.ts): require functions whose return type is `Promise` to be declared with the `async` keyword so synchronous throws surface as a rejected Promise (type-aware). - [`typescript/related-getter-setter-pairs`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-related-getter-setter-pairs.ts): reject a `get` accessor whose declared return type does not match the parameter type of its companion `set` accessor on the same class, readers should not observe a type the writer cannot accept (type-aware). - [`typescript/require-array-sort-compare`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-require-array-sort-compare.ts): require `arr.sort()` and `arr.toSorted()` calls to pass an explicit `compareFunction`. - [`typescript/require-await`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/require-await.ts): reject `async` functions that have no `await` expression and return no promise. - [`typescript/restrict-plus-operands`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-restrict-plus-operands.ts): rejects `+` expressions whose operands are not both `number`, both `string`, or both `bigint` (type-aware). - [`typescript/restrict-template-expressions`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-restrict-template-expressions.ts): reject template-literal interpolations whose expression carries a type that does not stringify cleanly, `${obj}` prints `"[object Object]"`, `${null}` prints `"null"`, and so on. - [`typescript/return-await`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/return-await.ts): reject `return promise` inside `try`, `catch`, or `finally`; require `return await promise`. - [`typescript/sort-type-constituents`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-sort-type-constituents.ts): sort the members of union (`A | B | C`) and intersection (`A & B & C`) types into a canonical order so reorderings don't show up as diffs. - [`typescript/strict-boolean-expressions`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-strict-boolean-expressions.ts): rejects non-boolean values used in a boolean context such as `if`, `&&`, `||`, or `!` (type-aware). - [`typescript/switch-exhaustiveness-check`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-switch-exhaustiveness-check.ts): requires every enumerable discriminant member to have an explicit `case` by default; typed options control real/comment defaults and open types (type-aware). - [`typescript/triple-slash-reference`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/triple-slash-reference/violation.ts): rejects triple-slash reference directives. - [`typescript/unbound-method`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/typescript-unbound-method.ts): reject referencing a class instance method as a value instead of calling it (`obj.method` passed as a callback, aliased to a variable, or stored on another object). - [`typescript/use-unknown-in-catch-callback-variable`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/use-unknown-in-catch-callback-variable.ts): require the callback parameter of `.catch(...)` and the second argument of `.then(...)` to be typed `unknown`. ### React React TSX rules, Hooks correctness, JSX safety, the React Compiler subset, and Fast Refresh export shape. Bundles rules from three upstream plugins under one `react/*` namespace, matching Oxlint's layout. Performance-only rules live in [React performance](#react-performance) because they are opt-in toggles rather than correctness checks. Source: [`eslint-plugin-react`](https://github.com/jsx-eslint/eslint-plugin-react), [`eslint-plugin-react-hooks`](https://github.com/facebook/react/tree/main/packages/eslint-plugin-react-hooks), [`eslint-plugin-react-refresh`](https://github.com/ArnaudBarre/eslint-plugin-react-refresh). - [`react/button-has-type`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-button-has-type.tsx): requires explicit valid `type` values on JSX `button` elements. - [`react/component-hook-factories`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-component-hook-factories.tsx): rejects nested component or Hook factories that call Hooks. - [`react/display-name`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-display-name.tsx): require components wrapped in `React.memo(...)` or `React.forwardRef(...)` to be named, either by passing a named function, assigning the call to a named binding, or setting an explicit `displayName`. - [`react/exhaustive-deps`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-exhaustive-deps.tsx): reports high-confidence missing identifier dependencies in `useEffect`, `useLayoutEffect`, `useInsertionEffect`, `useMemo`, and `useCallback`. - [`react/iframe-missing-sandbox`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-iframe-missing-sandbox.tsx): requires JSX `iframe` elements to include a sandbox attribute. - [`react/immutability`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-immutability.tsx): rejects local prop mutation inside components and Hooks. - [`react/jsx-key`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-jsx-key.tsx): requires `key` props for JSX elements produced by arrays or `.map()`. - [`react/jsx-no-duplicate-props`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-jsx-no-duplicate-props.tsx): rejects duplicate JSX prop names on the same element. - [`react/jsx-no-script-url`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-jsx-no-script-url.tsx): rejects `javascript:` URLs in JSX URL-like props. - [`react/jsx-no-target-blank`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-jsx-no-target-blank.tsx): reject `` (or any JSX element with `target="_blank"`) that does not also carry `rel="noreferrer"` (or `rel="noopener noreferrer"`). - [`react/jsx-no-undef`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-jsx-no-undef.tsx): reject JSX elements whose tag is an uppercase identifier with no value-level declaration anywhere in the source file. - [`react/jsx-no-useless-fragment`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-jsx-no-useless-fragment.tsx): reject JSX fragments that wrap exactly one element child or have no meaningful content. The child (or nothing) can be returned directly. - [`react/no-array-index-key`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-array-index-key.tsx): rejects array map index parameters as JSX keys. - [`react/no-children-prop`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-children-prop.tsx): rejects passing children through a JSX `children` prop. - [`react/no-danger`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-danger.tsx): rejects `dangerouslySetInnerHTML`. - [`react/no-danger-with-children`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-danger-with-children.tsx): rejects combining `dangerouslySetInnerHTML` with children. - [`react/no-direct-mutation-state`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-direct-mutation-state.tsx): rejects direct writes to `this.state` outside constructor initialization. - [`react/no-find-dom-node`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-find-dom-node.tsx): rejects `findDOMNode` calls. - [`react/no-is-mounted`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-is-mounted.tsx): rejects `isMounted` calls. - [`react/no-string-refs`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-string-refs.tsx): rejects string JSX refs. - [`react/no-unescaped-entities`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-no-unescaped-entities.tsx): rejects unescaped `>`, `"`, `'`, and `}` in JSX text. - [`react/only-export-components`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-only-export-components.tsx): keeps React Fast Refresh component modules from exporting non-components. - [`react/refs`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-refs.tsx): rejects reading or writing `ref.current` during render. - [`react/rules-of-hooks`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-rules-of-hooks.tsx): rejects Hooks called outside components or custom Hooks, in nested callbacks, or in conditional/loop control flow. - [`react/set-state-in-effect`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-set-state-in-effect.tsx): rejects synchronous setter calls inside `useEffect`. - [`react/set-state-in-render`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-set-state-in-render.tsx): rejects `useState` / `useReducer` setters called during render. - [`react/style-prop-object`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-style-prop-object.tsx): rejects string literal JSX `style` prop values. - [`react/use-memo`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-use-memo.tsx): rejects block-bodied `useMemo` callbacks that do not return a value. - [`react/void-dom-elements-no-children`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-void-dom-elements-no-children.tsx): rejects children and HTML injection props on void DOM elements. ### React performance Detects freshly-allocated reference values (arrays, objects, functions, JSX elements) passed as JSX props. A new reference invalidates `React.memo` / `useMemo` shallow checks on every render. Useful for performance-critical render paths; usually unnecessary for top-level pages. Diagnostics only fire on `.tsx` source files, JSX heuristics rely on the file extension, so `.ts` files are skipped even when they contain JSX-like syntax. Source: [`eslint-plugin-react-perf`](https://github.com/cvazac/eslint-plugin-react-perf). - [`react-perf/jsx-no-jsx-as-prop`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-perf-jsx-no-jsx-as-prop.tsx): rejects freshly-created JSX elements or fragments passed as JSX props. - [`react-perf/jsx-no-new-array-as-prop`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-perf-jsx-no-new-array-as-prop.tsx): rejects freshly-created arrays passed as JSX props. - [`react-perf/jsx-no-new-function-as-prop`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-perf-jsx-no-new-function-as-prop.tsx): rejects freshly-created functions passed as JSX props. - [`react-perf/jsx-no-new-object-as-prop`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/react-perf-jsx-no-new-object-as-prop.tsx): rejects freshly-created objects passed as JSX props. ### JSX accessibility JSX accessibility rules applied to TSX (and JSX-in-TS) sources. Checks the static structure of JSX elements against WAI-ARIA authoring guidance, interactive controls should be focusable, labels should reference a control, ARIA properties should match the element role, and so on. Runtime accessibility issues require live audits; this family catches the statically-decidable subset. Component alias settings, router-specific anchor settings, and autofixes are deferred. Source: [`eslint-plugin-jsx-a11y`](https://github.com/jsx-eslint/eslint-plugin-jsx-a11y). - [`jsx-a11y/alt-text`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-alt-text.tsx): requires image-like JSX elements to expose alt text or an ARIA label. - [`jsx-a11y/anchor-ambiguous-text`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-anchor-ambiguous-text.tsx): rejects `` elements whose visible text is a phrase that carries no information out of context. - [`jsx-a11y/anchor-has-content`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-anchor-has-content.tsx): rejects empty JSX anchors with no accessible content. - [`jsx-a11y/anchor-is-valid`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-anchor-is-valid.tsx): rejects anchors with missing, `#`-only, empty, or `javascript:` `href` values. - [`jsx-a11y/aria-activedescendant-has-tabindex`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-aria-activedescendant-has-tabindex.tsx): requires `tabIndex` on any element carrying `aria-activedescendant` that is not focusable by default. - [`jsx-a11y/aria-props`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-aria-props.tsx): rejects `aria-*` JSX attribute names that are not part of the WAI-ARIA spec. - [`jsx-a11y/aria-proptypes`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-aria-proptypes.tsx): validates literal ARIA property values against the type the spec declares for them. - [`jsx-a11y/aria-role`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-aria-role.tsx): requires `role` values to be a concrete, non-abstract WAI-ARIA role. - [`jsx-a11y/aria-unsupported-elements`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-aria-unsupported-elements.tsx): rejects ARIA roles and attributes on elements that do not support them. - [`jsx-a11y/autocomplete-valid`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-autocomplete-valid.tsx): validates literal `autocomplete` tokens against the HTML spec and the surrounding input `type`. - [`jsx-a11y/click-events-have-key-events`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-click-events-have-key-events.tsx): requires keyboard handlers alongside `onClick` on non-interactive JSX elements. - [`jsx-a11y/control-has-associated-label`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-control-has-associated-label.tsx): requires interactive controls to have an accessible label. - [`jsx-a11y/heading-has-content`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-heading-has-content.tsx): rejects empty JSX headings. - [`jsx-a11y/html-has-lang`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-html-has-lang.tsx): requires `` JSX elements to declare a non-empty `lang` attribute. - [`jsx-a11y/iframe-has-title`](https://github.com/samchon/ttsc/blob/master/packages/lint/test/testdata/corpus/jsx-a11y-iframe-has-title.tsx): requires every `