@astral-sh/ruff-wasm-bundler

Ruff WASM

⚠️ WARNING: This API is experimental and may change at any time

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An extremely fast Python linter and code formatter, written in Rust.

This is a WASM version of the Ruff API which can be used to lint/format Python in a browser environment.

There are multiple versions for the different wasm-pack targets. See here for more info on targets.

• Bundler
• Web
• Node.js

Usage

This example uses the wasm-pack web target and is known to work with Vite.

import init, { Workspace, type Diagnostic } from '@astral-sh/ruff-api';

const exampleDocument = `print('hello'); print("world")`

await init(); // Initializes WASM module

// These are default settings just to illustrate configuring Ruff
// Settings info: https://docs.astral.sh/ruff/settings
const workspace = new Workspace({
  'line-length': 88,
  'indent-width': 4,
  format: {
    'indent-style': 'space',
    'quote-style': 'double',
  },
  lint: {
    select: [
      'E4',
      'E7',
      'E9',
      'F'
    ],
  },
});

// Will contain 1 diagnostic code for E702: Multiple statements on one line
const diagnostics: Diagnostic[] = workspace.check(exampleDocument);

const formatted = workspace.format(exampleDocument);

Changelog

0.6.0

Check out the blog post for a migration guide and overview of the changes!

Breaking changes

See also, the "Remapped rules" section which may result in disabled rules.

• Lint and format Jupyter Notebook by default (#12878).
• Detect imports in src layouts by default for isort rules (#12848)
• The pytest rules PT001 and PT023 now default to omitting the decorator parentheses when there are no arguments (#12838).

Deprecations

The following rules are now deprecated:

• pytest-missing-fixture-name-underscore (PT004)
• pytest-incorrect-fixture-name-underscore (PT005)
• unpacked-list-comprehension (UP027)

Remapped rules

The following rules have been remapped to new rule codes:

• unnecessary-dict-comprehension-for-iterable: RUF025 to C420

Stabilization

The following rules have been stabilized and are no longer in preview:

• singledispatch-method (PLE1519)
• singledispatchmethod-function (PLE1520)
• bad-staticmethod-argument (PLW0211)
• if-stmt-min-max (PLR1730)
• invalid-bytes-return-type (PLE0308)
• invalid-hash-return-type (PLE0309)
• invalid-index-return-type (PLE0305)
• invalid-length-return-type (PLEE303)
• self-or-cls-assignment (PLW0642)
• byte-string-usage (PYI057)
• duplicate-literal-member (PYI062)
• redirected-noqa (RUF101)

The following behaviors have been stabilized:

• cancel-scope-no-checkpoint (ASYNC100): Support asyncio and anyio context mangers.
• async-function-with-timeout (ASYNC109): Support asyncio and anyio context mangers.
• async-busy-wait (ASYNC110): Support asyncio and anyio context mangers.
• async-zero-sleep (ASYNC115): Support anyio context mangers.
• long-sleep-not-forever (ASYNC116): Support anyio context mangers.

The following fixes have been stabilized:

• superfluous-else-return (RET505)
• superfluous-else-raise (RET506)
• superfluous-else-continue (RET507)
• superfluous-else-break (RET508)

Preview features

• [flake8-simplify] Further simplify to binary in preview for (SIM108) (#12796)
• [pyupgrade] Show violations without auto-fix (UP031) (#11229)

Rule changes

• [flake8-import-conventions] Add xml.etree.ElementTree to default conventions (#12455)
• [flake8-pytest-style] Add a space after comma in CSV output (PT006) (#12853)

Server

• Show a message for incorrect settings (#12781)

Bug fixes

• [flake8-async] Do not lint yield in context manager (ASYNC100) (#12896)
• [flake8-comprehensions] Do not lint async for comprehensions (C419) (#12895)
• [flake8-return] Only add return None at end of a function (RET503) (#11074)
• [flake8-type-checking] Avoid treating dataclasses.KW_ONLY as typing-only (TCH003) (#12863)
• [pep8-naming] Treat type(Protocol) et al as metaclass base (N805) (#12770)
• [pydoclint] Don't enforce returns and yields in abstract methods (DOC201, DOC202) (#12771)
• [ruff] Skip tuples with slice expressions in (RUF031) (#12768)
• [ruff] Ignore unparenthesized tuples in subscripts when the subscript is a type annotation or type alias (RUF031) (#12762)
• [ruff] Ignore template strings passed to logging and builtins._() calls (RUF027) (#12889)
• [ruff] Do not remove parens for tuples with starred expressions in Python <=3.10 (RUF031) (#12784)
• Evaluate default parameter values for a function in that function's enclosing scope (#12852)

Other changes

• Respect VS Code cell metadata when detecting the language of Jupyter Notebook cells (#12864)
• Respect kernelspec notebook metadata when detecting the preferred language for a Jupyter Notebook (#12875)