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Rslint

    prefer-to-have-length

    Added in v0.4.2

    Configuration

    PresetConfigured Value
    ✅ jestPlugin.configs.all"error"
    ✅ jestPlugin.configs.style"error"
    rslint.config.ts
    import { defineConfig, jestPlugin } from '@rslint/core';

export default defineConfig([
  jestPlugin.configs.recommended,
  {
    rules: {
      'jest/prefer-to-have-length': 'error',
    },
  },
]);

    Rule Details

    Prefer toHaveLength() when asserting the length of a value. It produces clearer failure output than comparing .length with toBe(), toEqual(), or toStrictEqual().

    Examples of incorrect code for this rule:

    expect(files.length).toBe(1);

expect(files.length).toEqual(1);

expect(files.length).toStrictEqual(1);

    Examples of correct code for this rule:

    expect(files).toHaveLength(1);

    Original Documentation