jest/no-hooks Style

What it does

Disallows Jest setup and teardown hooks, such as beforeAll.

Why is this bad?

Jest provides global functions for setup and teardown tasks, which are called before/after each test case and each test suite. The use of these hooks promotes shared state between tests.

This rule reports for the following function calls:

• beforeAll
• beforeEach
• afterAll
• afterEach

Examples

Examples of incorrect code for this rule:

function setupFoo(options) {/* ... */}
function setupBar(options) {/* ... */}

describe("foo", () => {
  let foo;
  beforeEach(() => {
    foo = setupFoo();
  });
  afterEach(() => {
    foo = null;
  });
  it("does something", () => {
    expect(foo.doesSomething()).toBe(true);
  });
  describe("with bar", () => {
    let bar;
    beforeEach(() => {
      bar = setupBar();
    });
    afterEach(() => {
      bar = null;
    });
    it("does something with bar", () => {
      expect(foo.doesSomething(bar)).toBe(true);
    });
  });
});

How to use

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

CLI

oxlint --deny jest/no-hooks --jest-plugin

Config (.oxlintrc.json)

{
  "plugins": ["jest"],
  "rules": {
    "jest/no-hooks": "error"
  }
}

References

• Rule Source