jest/no-duplicate-hooks Style

What it does

A describe block should not contain duplicate hooks.

Example

// invalid
describe("foo", () => {
  beforeEach(() => {
    // some setup
  });
  beforeEach(() => {
    // some setup
  });
  test("foo_test", () => {
    // some test
  });
});

// Nested describe scenario
describe("foo", () => {
  beforeEach(() => {
    // some setup
  });
  test("foo_test", () => {
    // some test
  });
  describe("bar", () => {
    test("bar_test", () => {
      afterAll(() => {
        // some teardown
      });
      afterAll(() => {
        // some teardown
      });
    });
  });
});

// valid
describe("foo", () => {
  beforeEach(() => {
    // some setup
  });
  test("foo_test", () => {
    // some test
  });
});

// Nested describe scenario
describe("foo", () => {
  beforeEach(() => {
    // some setup
  });
  test("foo_test", () => {
    // some test
  });
  describe("bar", () => {
    test("bar_test", () => {
      beforeEach(() => {
        // some setup
      });
    });
  });
});

References

• Rule Source