## Releases & change log

This document chronicles quick-lint-js' releases. This document's format is based on Keep a Changelog.

quick-lint-js' version numbers are arbitrary. quick-lint-js does not adhere to Semantic Versioning.

### 2.3.0 (2022-02-24)

Downloads

#### Added

- An incomplete `class` now reports E0199 instead of failing with the catch-all E0054. (Thanks to Dave Churchill for reporting.)
- Statements before the first `case` in a `switch` now report E0198 (implemented by Himanshu).
- When building from source, you can tell quick-lint-js to use your copy of third-party dependencies instead of quick-lint-js' bundled dependencies:
  - `-DQUICK_LINT_JS_USE_BUNDLED_BOOST=OFF`: Use your own copy of Boost.
  - `-DQUICK_LINT_JS_USE_BUNDLED_GOOGLE_BENCHMARK=OFF`: Use your own copy of Google Benchmark (benchmarks only).
  - `-DQUICK_LINT_JS_USE_BUNDLED_GOOGLE_TEST=OFF`: Use your own copy of Google Test (tests only).
  - `-DQUICK_LINT_JS_USE_BUNDLED_SIMDJSON=OFF`: Use your own copy of simdjson.

### 2.2.0 (2022-02-17)

Downloads

#### Fixed

- `x && <Element/>` no longer falsely reports E0026 (missing operand for operator). (Thanks to Piotr Dąbrowski for reporting.)
- In top-level code, `await <x/>` is now parsed as the `await` operator followed by a JSX element (rather than `await` less-than-compared to `x`, followed by jibberish).

#### Changed

- Homebrew: Emacs Lisp files are now installed in `<brew>/share/emacs/site-lisp/quick-lint-js` (per `brew audit`'s recommendation) instead of in `share/emacs/site-lisp`.

### 2.1.0 (2022-02-09)

Downloads

#### Fixed

- Curried arrow functions like `a => b => { a; b; }` no longer falsely reports E0057. (Thanks to Christian Mund for reporting.)

### 2.0.0 (2022-02-08)

Downloads

#### Added

- quick-lint-js now supports JSX syntax in both .js and .jsx files.
- New diagnostics for JSX: E0019, E0181, E0182, E0183, E0186, E0187, E0189, E0191, E0192, E0193
- `if (...) {...} else (...) {...}` now reports E0184 ('missing `if` after `else`') (implemented by Himanshu).
- `if (x = "")` now reports E0188 ('`=` changes variables; to compare, use `===` instead').
- `if (a == "X" || "Y")` now reports E0190 ('missing comparison; `===` does not extend to the right side of `||`').
- `async (param1, param2) {}` now reports E0176 ('missing arrow operator for arrow function'). (E0176 was previously reported only for non-`async` arrow functions.)
- `let x = 'nah'; if (y) { let x = 'yah'; }` now reports E0196 ('new variable shadows existing variable'). This warning is reported only when an assignment (instead of a new variable declaration) was intended.
- `console.log(“hello world”);` now reports E0197 (''“' is not allowed for strings; use " instead').
- `-1 ** 2` now reports E0194 (missing parentheses around left-hand side of `**`).
- `typeof 10 ** 7` now reports E0195 (missing parentheses around operand of `typeof`).

#### Fixed

- LSP: When responding to unsupported methods with error code -32601, quick-lint-js now includes the request ID. (Previously, the `"id"` field was always `null`.)
- CLI: If a crash occurs due to E0054 or E0203, the CLI no longer crashes (e.g. with an illegal instruction error).
- quick-lint-js no longer ignores elements of assigned arrays. For example, `[fisrt, second] = s.split(' ');` will now report E0057 for `fisrt` (if `fisrt` is not declared).
- quick-lint-js no longer incorrectly reports E0176 (missing arrow operator for arrow function) if the `extends` clause for a class is parenthesized and contains commas (e.g. `class A extends (B, C) {}`).
- quick-lint-js no longer incorrectly reports E0016, E0038, E0060, or E0207 in tagged template literals. (These errors are still reported for untagged template literals and for string literals.)

#### Changed

- Assigning to an imported variable now reports E0185 ('assignment to imported variable') instead of E0003 ('assignment to const variable') (implemented by Matheus de Sousa).

### 1.0.0 (2021-12-13)

Downloads

#### Added

- Windows: Clang-cl is now able to compile quick-lint-js for Windows.
- E0176 is now reported if the desired arrow function has more than zero parameters.
- E0178 is now reported if the arrow function appears in top-level code or inside a non-async function.

#### Fixed

- Arch Linux: The quick-lint-js package now installs correctly if you have another Vim plugin package installed. The installation error was: "error: failed to commit transaction (conflicting files)"
- `(typeof x)=>{}` and similar code now reports E0151 (invalid function parameter) instead of E0019 (invalid binding in let statement).
- `([(x,)] => {})` now declares `x` as a parameter instead of ignoring `x` entirely. (It still produces E0180).
- `\u0` at the end of a file now reports E0016 (expected hexadecimal digits in Unicode escape sequence) instead of E0038 (unclosed identifier escape sequence)
- `"\u{00a0:"` now reports only one error (E0038 (unclosed identifier escape sequence)) instead of two (E0038 and E0040 (unclosed string literal)).
- After reporting E0178, the arrow function is parsed as if it was async, allowing the body to use `await` as an operator without error.

#### Changed

- E0013 is no longer reported for identifiers such as `bird\u{360000}`. E0207 is reported instead.

#### Optimized

- The Windows .exe is 51% smaller (2.30 MiB -> 1.14 MiB) by making a hash table used for translations compile-time-only. See the patch here.

### 0.7.1 (2021-12-06)

Beta release.

Downloads

#### Added

- npm: The npm package now installs on Windows when using the x86 (32-bit) version of Node.js.
- E0036 is now reported in more situations.

#### Fixed

- npm: The npm package now installs on macOS Apple Silicon when using the AArch64 (native) version of Node.js. (The package previously worked only on macOS Intel, or when using x86_64 Node.js with Rosetta.)

### 0.7.0 (2021-12-05)

Beta release.

Downloads

#### Security

- The source archive (`quick-lint-js-*.tar.gz`) is now signed with our GPG key.
- Arch Linux: The release package on AUR now verifies that the source archive is signed with our GPG key.

#### Added

- New diagnostics: E0053, E0179
- Improve error reporting of `console.("hello")` and similar code.
- Reported errors now include a link to the website for a detailed explanation (implemented by Amir).
- CLI: New `--diagnostic-hyperlinks` option (implemented by Amir).
- CLI: Fish and Zsh completions for the `--output-format` option now include documentation for each value (implemented by Amir).

#### Fixed

- Reporting E0144 no longer also reports E0057.
- Variables can be named according to Unicode 14 (previously Unicode 13).
- `void 0?a:b=c` no longer reports E0020.
- Vim: The Debian package, the Arch Linux package, and the Homebrew package now install the coc.nvim plugin and the plugin documentation.
- Neovim: Fixed with newer versions of nvim-lspconfig (since commit 97da7ed12e published November 25, 2021).

#### Optimized

- Identifier parsing is now SIMD-optimized for ARM systems, including Apple Silicon. See the patch here.
- Diagnostic message translations consume less space in executables and also take less time to process. See the patch here.
- Expression ASTs are now garbage-collected during parsing, reducing peak memory usage (and as a side effect making parsing faster). See the patch here.

### 0.6.0 (2021-11-20)

Beta release.

Downloads

#### Added

- Various new diagnostics (implemented by Himanshu and Matheus de Sousa).
- VS Code: The new `quick-lint-js.logging` setting allows you to show quick-lint-js' internal log messages in an Output window.
- VS Code: Apple Silicon (e.g. M1) (ARM64) is now supported.
- VS Code: Linux ARM (32-bit) is now supported.
- Vim: Improved performance for ALE versions v2.5.0 and newer (and v3.0.0 and newer). You should configure `g:ale_lint_on_text_changed` to `'always'` for the best experience.
- Vim: Improved performance of the ALE plugin by using the LSP server by default.
- The macOS and Windows binaries are now code-signed.
- Emacs (Eglot): You no longer need to type `M-x eglot` in order to start linting. Apply this fix by adding `(eglot-ensure)` to your init file.
- quick-lint-js now understands the `AggregateError`, `FinalizationRegistry`, and `WeakRef` ECMAScript global variables by default.
- The macOS and Windows executables now include embedded code signatures. These signatures are made with a self-signed certificate.
- The Linux executables are now signed with a GPG signature (`.asc` files).
- Vim: coc.nvim is now supported.
- quick-lint-js has a new mascot, Dusty. Say hello! (Artwork by Jenny "Jennipuff" Wheat).
- Translations: German (implemented by Nico Sonack)

#### Fixed

- macOS: quick-lint-js no longer hangs if a file is changed in your home directory or project directory.
- Various crashes on invalid code have been fixed.
- quick-lint-js consumes less memory for pathological code patterns.
- VS Code: The extension no longer tries to load an ARM64 DLL on Windows x64.
- The npm package and the manual builds are now much smaller and faster. (They were previously compiled in debug, unoptimized mode.)
- `delete x` no longer reports a warning if `x` is a global variable.
- JSX: Instead of reporting a bunch of errors, quick-lint-js now tells you that JSX syntax is not yet supported.
- FreeBSD: Fixed build.
- E0073, E0094, E0104, E0106, E0111, and E0119 now point to a more helpful place (implemented by strager and Amir).
- `for (let x = a in b; c; d) {}` now reports E0108 instead of reporting E0173, E0110, and E0110 again.

#### Changed

- Error codes now have four decimal digits instead of three. For example, E001 is now called E0001.
- LSP benchmarks have been rewritten. The new benchmarks should produce more stable numbers and be fairer to linters with a high start-up time such as Flow.

#### Removed

- quick-lint-js no longer looks for files named `.quick-lint-js.config`. To configure quick-lint-js, name your file `quick-lint-js.config` instead.

### 0.5.0 (2021-10-12)

Beta release.

Downloads

#### Added

- Various new errors (implemented by Himanshu).
- `quick-lint-js.config` now supports the literally-anything global group. Use this option to disable all use-of-undeclared-variable warnings.
- If quick-lint-js crashes, it will link to a page to report crashes.
- VS Code: The plugin now works on Windows on ARM (64-bit).
- VS Code: The plugin now works on Linux on ARM (32-bit and 64-bit).
- The CLI and LSP server now compile on FreeBSD (amd64). However, we don't provide FreeBSD pre-built executables.
- Neovim: nvim-lspconfig is now supported by quick-lint-js' plugin (implemented by tiagovla).
- VS Code: Contributors can now enable performance tracing (implemented by Jimmy Qiu).

#### Fixed

- LSP, VS Code: Filesystem change watching failures no longer crash. These failures can happen on Windows for directories on network shares, for example.
- LSP: Unknown messages no longer crash the LSP server. This makes the LSP server compatible with more clients, such as Neovim's built-in client.
- `break await` and `break yield` no longer incorrectly reports errors (fixed by Himanshu).
- `for (var x = ++y in []) {}` now parses correctly as valid JavaScript.
- Vim: The plugin no longer crashes if a filename contains a newline character (or certain other control characters).
- LSP, VS Code: Config file changes are now recognized properly if any path component contains a symbolic link (Linux and macOS).
- quick-lint-js no longer warns about variables named `__dirname`, `__filename`, `exports`, `module`, or `require` by default.
- Parsing certain code patterns containing `await/` no longer takes excessive memory and time.
- Various crashes on invalid code have been fixed.
- LSP, VS Code: Some memory leaks have been fixed.
- Arch Linux: building should no longer fail with "The install of the quick-lint-js target requires changing an RPATH from the build tree".

### 0.4.0 (2021-09-09)

Beta release.

Downloads

#### Changed

- CLI: The `--stdin` option (and `-`) no longer search for configuration files in the current working directory. Use the `--path-for-config-search` option to approximate the old behavior.
- Emacs: For scratch buffers, the Flycheck and Flymake plugins no longer search for configuration files.
- Vim: For unnamed buffers, the ALE plugin no longer searches for configuration files in the current working directory's parent and ancestors. Name the buffer using the `:file` command if you want a configuration file to take effect.
- VS Code: The plugin has been rewritten. Performance should be better, but stability and compatibility might suffer. For example, VS Code on Apple silicon (AArch64 CPUs) has not been tested and will likely no longer work. Please report compatibility issues.

#### Added

- Various new errors (implemented by Himanshu)
- CLI: `--path-for-config-search` allows customizing where configuration files are found for `--stdin`
- Global variables for several popular libraries are now recognized by default, including jQuery, Jasmine, and Jest
- Syntax and schema errors in `quick-lint-js.config` no longer crash quick-lint-js. Instead, these errors are highlighted similar to errors in JavaScript files.
- VS Code: `quick-lint-js.config` is now used when linting opened JavaScript files.

#### Fixed

- Building quick-lint-js with AddressSanitizer on Fedora no longer fails in `collect-copyright`
- Building quick-lint-js no longer fails if a directory called `brew` exists anywhere in `$PATH`
- Various crashes given invalid JavaScript no longer happen (implemented by wagner riffel and David Vasileff)
- `for (const x of xs)` no longer incorrectly reports E205 (missing initializer in const declaration) (fixed by Himanshu)
- Windows: `quick-lint-js.config` files are now recognized if the containing directory contains non-ASCII characters
- Fix SSE2 corruption on 32-bit Windows builds with MSVC.

### 0.3.0 (2021-07-02)

Beta release.

Downloads

#### Security

- Vim plugin: Version 0.2.0 executed `node_modules/.bin/quick-lint-js` without validating that the program is really quick-lint-js. The plugin now conservatively ignores `quick-lint-js` in `node_modules` by default.

#### Added

- New JS syntax: `.?`, class fields, `import.meta`, top-level `await`, `#privateProperties`
- Translations: Swedish (implemented by Kim "Linden")
- Emacs plugin (implemented by wagner riffel)
- Neovim plugin
- Errors and warnings are now documented on the website
- Various new errors and error message improvements (implemented by AidenThing, Daniel La Rocque, Erlliam Mejia, Himanshu, Lee Wannacott, [Matheus Sousa][])
- Shell completion for the CLI (Bash, Fish, Zsh) (implemented by Shivam Mehta)
- `--stdin` CLI option allows reading JavaScript from standard input instead of a file (implemented by wagner riffel)
- Partially implemented: Global variables can be configured using a `quick-lint-js.config` file

#### Fixed

- Using browser variables such as `document` and `window` no longer reports undesired undeclared variable warnings
- `with` statements and `eval` no longer cause spurious undeclared variable warnings (implemented by Himanshu)
- `++a[0];` no longer reports an assignment-to-const-variable error if `a` was declared with `const` (implemented by Himanshu)
- `'undefined' === typeof foo ? 3 : 4` no longer reports a warning that `foo` is undeclared (implemented by Himanshu)
- Building tests with GCC 11.1.1 no longer fails due to `-Werror`
- Various crashes given invalid JavaScript no longer happen
- Building the VS Code plugin now works on Windows (implemented by Jimmy Qiu)

### 0.2.0 (2021-04-05)

Beta release.

Downloads