Eslint-plugin-rxjs-x NPM

eslint-plugin-rxjs-x

This ESLint plugin is intended to prevent issues with RxJS.

Most of these rules require TypeScript typed linting and are indicated as such below.

Migrating from `eslint-plugin-rxjs`

This project is a fork of eslint-plugin-rxjs initially started to support the new ESLint flat config format. There are some breaking changes:

The old .eslintrc format is not supported.
- If you need to continue using this old format, use the original eslint-plugin-rxjs or a different fork.
The plugin namespace specified in the recommended config was changed from rxjs to rxjs-x.
- e.g. In your ESLint config, rxjs/no-subject-value should be renamed to rxjs-x/no-subject-value.
The rule rxjs/no-ignored-observable is renamed to rxjs-x/no-floating-observables.

A complete description of all changes are documented in the CHANGELOG file.

Install

See typescript-eslint's Getting Started for a full ESLint setup guide.

Then use the recommended configuration in your eslint.config.mjs and enable typed linting:

// @ts-check
import tseslint from 'typescript-eslint';
import rxjsX from 'eslint-plugin-rxjs-x';

export default tseslint.config({
    extends: [
        ...tseslint.configs.recommended,
        rxjsX.configs.recommended,
    ],
    languageOptions: {
        parserOptions: {
            projectService: true,
        },
    },
});

The above example uses typescript-eslint's built-in config to set up the TypeScript parser for us. Enabling projectService then turns on typed linting. See Linting with Type Information for details.

Configs

	Name
✅	`recommended`
🔒	`strict`

Rules

The package includes the following rules.

💼 Configurations enabled in.\ ✅ Set in the recommended configuration.\ 🔒 Set in the strict configuration.\ 🔧 Automatically fixable by the --fix CLI option.\ 💡 Manually fixable by editor suggestions.\ 💭 Requires type information.\ ❌ Deprecated.

Name	Description	💼	🔧	💡	💭	❌
ban-observables	Disallow banned observable creators.
ban-operators	Disallow banned operators.				💭
finnish	Enforce Finnish notation.				💭
just	Require the use of `just` instead of `of`.		🔧
macro	Require the use of the RxJS Tools Babel macro.		🔧			❌
no-async-subscribe	Disallow passing `async` functions to `subscribe`.	✅ 🔒			💭
no-compat	Disallow the `rxjs-compat` package.					❌
no-connectable	Disallow operators that return connectable observables.				💭
no-create	Disallow the static `Observable.create` function.	✅ 🔒			💭
no-cyclic-action	Disallow cyclic actions in effects and epics.				💭
no-explicit-generics	Disallow unnecessary explicit generic type arguments.
no-exposed-subjects	Disallow public and protected subjects.	🔒			💭
no-finnish	Disallow Finnish notation.				💭
no-floating-observables	Require Observables to be handled appropriately.	🔒			💭
no-ignored-default-value	Disallow using `firstValueFrom`, `lastValueFrom`, `first`, and `last` without specifying a default value.	🔒			💭
no-ignored-error	Disallow calling `subscribe` without specifying an error handler.	🔒			💭
no-ignored-notifier	Disallow observables not composed from the `repeatWhen` or `retryWhen` notifier.	✅ 🔒			💭
no-ignored-replay-buffer	Disallow using `ReplaySubject`, `publishReplay` or `shareReplay` without specifying the buffer size.	✅ 🔒
no-ignored-subscribe	Disallow calling `subscribe` without specifying arguments.				💭
no-ignored-subscription	Disallow ignoring the subscription returned by `subscribe`.				💭
no-ignored-takewhile-value	Disallow ignoring the value within `takeWhile`.	✅ 🔒
no-implicit-any-catch	Disallow implicit `any` error parameters in `catchError` operators.	✅ 🔒	🔧	💡	💭
no-index	Disallow importing index modules.	✅ 🔒
no-internal	Disallow importing internal modules.	✅ 🔒	🔧	💡
no-misused-observables	Disallow Observables in places not designed to handle them.	🔒			💭
no-nested-subscribe	Disallow calling `subscribe` within a `subscribe` callback.	✅ 🔒			💭
no-redundant-notify	Disallow sending redundant notifications from completed or errored observables.	✅ 🔒			💭
no-sharereplay	Disallow unsafe `shareReplay` usage.	✅ 🔒
no-subclass	Disallow subclassing RxJS classes.	🔒			💭
no-subject-unsubscribe	Disallow calling the `unsubscribe` method of subjects.	✅ 🔒			💭
no-subject-value	Disallow accessing the `value` property of a `BehaviorSubject` instance.				💭
no-subscribe-handlers	Disallow passing handlers to `subscribe`.				💭
no-subscribe-in-pipe	Disallow calling of `subscribe` within any RxJS operator inside a `pipe`.	✅ 🔒			💭
no-tap	Disallow the `tap` operator.					❌
no-topromise	Disallow use of the `toPromise` method.	✅ 🔒		💡	💭
no-unbound-methods	Disallow passing unbound methods.	✅ 🔒			💭
no-unsafe-catch	Disallow unsafe `catchError` usage in effects and epics.				💭
no-unsafe-first	Disallow unsafe `first`/`take` usage in effects and epics.				💭
no-unsafe-subject-next	Disallow unsafe optional `next` calls.	✅ 🔒			💭
no-unsafe-switchmap	Disallow unsafe `switchMap` usage in effects and epics.				💭
no-unsafe-takeuntil	Disallow applying operators after `takeUntil`.	✅ 🔒			💭
prefer-observer	Disallow passing separate handlers to `subscribe` and `tap`.	✅ 🔒	🔧	💡	💭
prefer-root-operators	Disallow importing operators from `rxjs/operators`.	✅ 🔒	🔧	💡
suffix-subjects	Enforce the use of a suffix in subject identifiers.				💭
throw-error	Enforce passing only `Error` values to `throwError`.	✅ 🔒			💭