bun.sh/test/js/node/assert/assert.spec.ts

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

describe("assert(expr)", () => {
  // https://github.com/oven-sh/bun/issues/941
  it.each([true, 1, "foo"])(`assert(%p) does not throw`, expr => {
    expect(() => assert(expr)).not.toThrow();
  });

  it.each([false, 0, "", null, undefined])(`assert(%p) throws`, expr => {
    expect(() => assert(expr)).toThrow(AssertionError);
  });

  it("is an alias for assert.ok", () => {
    expect(assert as Function).toBe(assert.ok);
  });
});

describe("assert.equal(actual, expected)", () => {
  it.each([
    ["foo", "foo"],
    [1, 1],
    [1, true],
    [0, ""],
    [0, false],
    [Symbol.for("foo"), Symbol.for("foo")],
  ])(`%p == %p`, (actual, expected) => {
    expect(() => assert.equal(actual, expected)).not.toThrow();
  });
  it.each([
    //
    ["foo", "bar"],
    [1, 0],
    [true, false],
    [{}, {}],
    [Symbol("foo"), Symbol("foo")],
    [new Error("oops"), new Error("oops")],
  ])("%p != %p", (actual, expected) => {
    expect(() => assert.equal(actual, expected)).toThrow(AssertionError);
  });
});

describe("assert.deepEqual(actual, expected)", () => {
  describe("error instances", () => {
    let e1: Error & Record<string, any>, e2: Error & Record<string, any>;

    beforeEach(() => {
      e1 = new Error("oops");
      e2 = new Error("oops");
    });

    it("errors with the same message and constructor are equal", () => {
      expect(() => assert.deepEqual(e1, e2)).not.toThrow();
    });

    it("errors with different messages are not equal", () => {
      e2.message = "nope";
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
    });

    it("errors with different constructors are not equal", () => {
      e2 = new TypeError("oops");
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
    });

    it("errors with different names are not equal", () => {
      e2.name = "SpecialError";
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
    });

    it("errors with different causes are not equal", () => {
      e1.cause = { property: "value" };
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
      e2.cause = { property: "another value" };
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
    });

    it("errors with the same cause are equal", () => {
      e1.cause = { property: "value" };
      e2.cause = { property: "value" };
      expect(() => assert.deepEqual(e1, e2)).not.toThrow();
    });

    it("adding different arbitrary properties makes errors unequal", () => {
      expect(() => assert.deepEqual(e1, e2)).not.toThrow();
      e1.a = 1;
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
      e2.a = 1;
      expect(() => assert.deepEqual(e1, e2)).not.toThrow();
      e2.a = { foo: "bar" };
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
      e1.a = { foo: "baz" };
      expect(() => assert.deepEqual(e1, e2)).toThrow(AssertionError);
    });
  });
});