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Rslint

    no-multiple-resolved

    Configuration

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

export default defineConfig([
  promisePlugin.configs.recommended,
  {
    rules: {
      'promise/no-multiple-resolved': 'error',
    },
  },
]);

    Disallow creating new promises where the executor can settle the promise more than once.

    Rule Details

    A Promise executor that calls both resolve and reject (or calls either one twice) on the same execution path settles the promise twice. The second settlement has no effect, but it indicates a logic error and can mask real bugs.

    Examples of incorrect code for this rule:

    new Promise((resolve, reject) => {
  if (error) {
    reject(error)
  }
  resolve(value) // may execute after reject
})

new Promise((resolve, reject) => {
  reject(error)
  resolve(value) // always executes after reject
})

new Promise(async (resolve, reject) => {
  try {
    const r = await foo()
    resolve()
    r() // can throw → catch may run after resolve
  } catch (error) {
    reject(error)
  }
})

    Examples of correct code for this rule:

    new Promise((resolve, reject) => {
  if (error) {
    reject(error)
  } else {
    resolve(value)
  }
})

new Promise((resolve, reject) => {
  if (error) {
    reject(error)
    return
  }
  resolve(value)
})

new Promise(async (resolve, reject) => {
  try {
    const r = await foo()
    resolve(r) // last throwable expression — catch cannot run after this
  } catch (error) {
    reject(error)
  }
})

    Differences from ESLint

    • Correlated conditions across separate if statements (e.g. if (err) { reject(err) } followed by if (!err) { resolve(val) }) are not recognized as mutually exclusive. This rule reports them as potential double-resolution. Full ESLint code-path analysis handles these; our simplified state-based analysis does not.

    • Calling an outer resolver multiple times inside a nested executor is reported here, whereas ESLint does not report it. For example:

      new Promise((resolve) => {
  new Promise((res) => {
    resolve(1)
    resolve(2) // rslint: reported — ESLint: not reported
  })
})

    Original Documentation