@jrc03c/js-math-tools/src/is-equal.test.mjs

some math tools for JS

import { copy } from "./copy.mjs"
import { DataFrame, Series } from "./dataframe/index.mjs"
import { expect, test } from "@jrc03c/fake-jest"
import { forEach } from "./for-each.mjs"
import { isEqual } from "./is-equal.mjs"

test("tests equality of primitives", () => {
  // Dates were causing this test to fail. See my note in the `isEqual`
  // function about how I'm choosing to handle date comparisons.
  const d1 = new Date(parseInt(Math.random() * new Date().getTime()))
  const d2 = new Date(parseInt(Math.random() * new Date().getTime()))
  expect(isEqual(d1, d1)).toBe(true)
  expect(isEqual(d1, d2)).toBe(false)

  const variables = [
    0,
    1,
    2.3,
    -2.3,
    Infinity,
    -Infinity,
    NaN,
    "foo",
    true,
    false,
    null,
    undefined,
    Symbol.for("Hello, world!"),
    new RegExp("Hello, world!"),
    [2, 3, 4],
    [
      [2, 3, 4],
      [5, 6, 7],
    ],
    x => x,
    function (x) {
      return x
    },
    { hello: "world" },
    new Series({ hello: [10, 20, 30, 40, 50] }),
    new DataFrame({ foo: [1, 2, 4, 8, 16], bar: [1, 3, 9, 27, 81] }),
  ]

  forEach(variables, item => {
    const clone = copy(item)
    expect(isEqual(item, clone)).toBe(true)

    if (typeof item === "object" && item !== null) {
      expect(item !== clone).toBe(true)
    }
  })

  // special cases
  const a1 = ["a", "b", "c"]
  const a2 = { 0: "a", 1: "b", 2: "c" }
  expect(isEqual(a1, a2)).toBe(false)

  const selfReferencer = [2, 3, 4]
  selfReferencer.push(selfReferencer)
  expect(isEqual(selfReferencer, copy(selfReferencer))).toBe(false)

  const b1 = { [Symbol.for("@foo")]: "bar" }
  const b2 = { [Symbol.for("@foo")]: "bar" }
  const b3 = {}
  expect(isEqual(b1, b2)).toBe(true)
  expect(isEqual(b2, b3)).toBe(false)

  expect(isEqual(new Date(), {})).toBe(false)
  expect(isEqual({}, new Date())).toBe(false)

  const c1 = new RegExp("foo")
  const c2 = new RegExp("bar")
  expect(isEqual(c1, c2)).toBe(false)
  expect(isEqual(c1, c1)).toBe(true)
  expect(isEqual(c2, c2)).toBe(true)
  expect(isEqual(c1, copy(c1))).toBe(true)
  expect(isEqual(c2, copy(c2))).toBe(true)

  expect(isEqual(234n, 234)).toBe(true)
  expect(isEqual(234n, 234n)).toBe(true)
  expect(isEqual(234, 234n)).toBe(true)
  expect(isEqual(1e3, 1000)).toBe(true)

  const e1 = { a: undefined, b: undefined, c: undefined }
  const e2 = { a: 3, b: 4, c: 5 }
  expect(isEqual(e1, e2)).toBe(false)
  expect(isEqual(e2, e1)).toBe(false)
})