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    callback-return

    Unreleased

    Configuration

    rslint.config.ts
    import { defineConfig } from '@rslint/core';

export default defineConfig([
  {
    plugins: ['node'],
    rules: {
      'node/callback-return': 'error',
    },
  },
]);

    Requires a return statement with callback calls to help prevent invoking a callback more than once.

    Rule Details

    This rule identifies callbacks by name. Within a function, a matching call must be inside a return, be the final callback expression in the function body, or immediately precede a return at the end of its enclosing block. Arrow functions with expression bodies return implicitly.

    A callback expression is a standalone call or the direct right operand of a binary or logical expression, such as cb && cb().

    Examples of incorrect code:

    function read(err, callback) {
  if (err) {
    callback(err);
  }
  callback();
}

    Examples of correct code:

    function read(err, callback) {
  if (err) {
    return callback(err);
  }
  callback();
}

function finish(err, cb) {
  if (err) {
    cb(err);
    return;
  }
  cb();
}

    Options

    The single option is an array of callback names. It defaults to ["callback", "cb", "next"]. A supplied array replaces those defaults; an empty array disables matching.

    export default [
  {
    plugins: ["node"],
    rules: {
      "node/callback-return": ["error", ["done", "send.error", "send.success"]],
    },
  },
];

    Names match the callee's exact source text. Object methods are supported when their receiver chain starts with an identifier. Spaces, comments, and computed property syntax are significant: send.error and send["error"] are different names.

    Differences from upstream

    In rslint, enable the node plugin and configure node/callback-return. The upstream rule is named n/callback-return.

    Known Limitations

    The rule does not track callback references passed to other functions, connect calls across nested functions, or infer that mutually exclusive branches invoke a callback only once. Calls outside functions are ignored. Optional calls such as cb?.() are not accepted as a final callback expression; use return cb?.() when returning from the function.

    This rule has no automatic fix or suggestions.

    Original Documentation