@jrc03c/js-math-tools/src/time.mjs

some math tools for JS

import { assert } from "./assert.mjs"
import { isFunction } from "./is-function.mjs"

function time(fn) {
  assert(isFunction(fn), "`fn` must be a function!")
  const start = performance.now()
  const temp = fn()

  if (temp instanceof Promise) {
    return new Promise((resolve, reject) => {
      try {
        temp.then(() => {
          const elapsed = performance.now() - start
          resolve(elapsed)
        })
      } catch (e) {
        return reject(e)
      }
    })
  } else {
    return performance.now() - start
  }
}

export { time }