jest/max-expects Style

What it does

This rule enforces a maximum number of expect() calls in a single test.

Why is this bad?

Tests with many different assertions are likely mixing multiple objectives. It is generally better to have a single objective per test to ensure that when a test fails, the problem is easy to identify.

Examples

Examples of incorrect code for this rule:

test("should not pass", () => {
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
});

it("should not pass", () => {
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
  expect(true).toBeDefined();
});

This rule is compatible with eslint-plugin-vitest, to use it, add the following configuration to your .oxlintrc.json:

{
  "rules": {
    "vitest/max-expects": "error"
  }
}

Configuration

This rule accepts a configuration object with the following properties:

max

type: integer

default: 5

Maximum number of expect() assertion calls allowed within a single test.

How to use

To enable this rule using the config file or in the CLI, you can use:

Config (.oxlintrc.json)

{
  "plugins": ["jest"],
  "rules": {
    "jest/max-expects": "error"
  }
}

CLI

oxlint --deny jest/max-expects --jest-plugin

References

• Rule Source