Iterables

.toBeIterableOf(expected)

Also available as an asymmetric matcher, expect.iterableOf(expected).

Use .toBeIterableOf to assert that a value is an iterable where each item matches the expected value, using deep equality.

.toBeStrictIterableOf(expected) and expect.strictIterableOf(expected) are also available to use strict deep equality.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable of the expected values", () => {
expect(array).toBeIterableOf(expect.any(Number));
expect(set).toBeIterableOf(expect.any(Number));
});

Tests

.toBeSequence(...sequence)

Also available as an asymmetric matcher, expect.sequenceMatching(...sequence).

Use .toBeSequence to assert that a value is an iterable with the exact sequence of values, using reference equality.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable with the exact sequence of values", () => {
expect(array).toBeSequence(1, 1, 2, 3);
expect(set).toBeSequence(1, 2, 3);
});

Tests

.toEqualSequence(...sequence)

Also available as an asymmetric matcher, expect.sequenceOf(...sequence).

Use .toEqualSequence to assert that a value is an iterable with the exact sequence of values.

.toStrictEqualSequence(...sequence) and expect.strictSequenceOf(...sequence) are also available to use strict deep equality.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable with the exact sequence of values", () => {
expect(array).toEqualSequence(1, 1, 2, 3);
expect(set).toEqualSequence(1, 2, 3);
});

Tests

.toSatisfySequence(...predicates)

Also available as an asymmetric matcher, expect.sequence(...predicates).

Use .toSatisfySequence to assert that a value is an iterable where each item satisfies the corresponding predicate.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable where each item satisfies the corresponding predicate", () => {
expect(array).toSatisfySequence(
  (value) => value === 1,
  (value) => value === 1,
  (value) => value === 2,
  (value) => value === 3
);
expect(set).toSatisfySequence(
  (value) => value === 1,
  (value) => value === 2,
  (value) => value === 3
);
});

Tests

.toContainSequence(...sequence)

Also available as an asymmetric matcher, expect.containingSequence(...sequence).

Use .toContainSequence to assert that a value is an iterable that contains the expected sequence of values, using reference equality.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable that contains the exact sequence of values", () => {
expect(array).toContainSequence(1, 2);
expect(set).toContainSequence(1, 2);
});

Tests

.toContainEqualSequence(...sequence)

Also available as an asymmetric matcher, expect.containingEqualSequence(...sequence).

Use .toContainEqualSequence to assert that a value is an iterable that contains the expected sequence of values, using deep equality.

.toContainStrictEqualSequence(...sequence) and expect.containingStrictEqualSequence(...sequence) are also available to use strict deep equality.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable that contains the exact sequence of values", () => {
expect(array).toContainEqualSequence(1, 2);
expect(set).toContainEqualSequence(1, 2);
});

Tests

.toContainSequenceSatisfying(...predicates)

Also available as an asymmetric matcher, expect.containingSequenceSatisfying(...predicates).

Use .toContainSequenceSatisfying to assert that a value is an iterable that contains the expected sequence of values, where each item satisfies the corresponding predicate.

const array = [1, 1, 2, 3];
const set = new Set(array);

it("is an iterable that contains the exact sequence of values", () => {
expect(array).toContainSequenceSatisfying(
  (value) => value === 1,
  (value) => value === 2
);
expect(set).toContainSequenceSatisfying(
  (value) => value === 1,
  (value) => value === 2
);
});

Tests