bun:test/prefer-hooks-on-top

A hook applies to every test in its block, no matter where it's written. A beforeEach below a test still runs before that test, but someone reading from the top hasn't seen it yet.

Each describe block is checked on its own.

Configure

Off by default. To turn it on:

[lint.rules]
"bun:test/prefer-hooks-on-top" = "error" # or "warn"

Examples

Reported:

import { beforeEach, expect, test } from "bun:test";

test("starts empty", () => {
  expect(cart.items).toHaveLength(0);
});

beforeEach(() => {
  cart.clear();
});

Not reported:

import { beforeEach, expect, test } from "bun:test";

beforeEach(() => {
  cart.clear();
});

test("starts empty", () => {
  expect(cart.items).toHaveLength(0);
});

A hook at the top of a describe block is fine, even if there's a test before the block:

import { beforeEach, describe, expect, test } from "bun:test";

test("loads the shop", () => {
  expect(shop.ready).toBe(true);
});

describe("cart", () => {
  beforeEach(() => {
    cart.clear();
  });

  test("starts empty", () => {
    expect(cart.items).toHaveLength(0);
  });
});