Run results for: Javascript string.endsWith vs string.slice and triple equal checking vs hardcoded index and triple equal, comparing a single character

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.4 Safari/605.1.15

Browser: Safari 18

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

slice

520.8M/s

hardcoded index

512.7M/s

endWith

79.5M/s

View exact numbers

Test name	Executions per second
✓ slice	520,795,168 Ops/sec
hardcoded index	512,696,160 Ops/sec
endWith	79,493,944 Ops/sec

Script Preparation code:

const value = "ABCDEF...WXYZ"
const ending = "Z"

function compareEndsWith(val, comparator) {
  return val.endsWith(comparator)
}
function compareSliceMethod(val, comparator) {
  const thingToCompare = val.slice(-1)
  return thingToCompare === comparator
}
function compareByIndex(val, comparator) {
	return value[12] === comparator
}

Tests:

endWith
const value = "ABCDEF...WXYZ" const ending = "Z" compareEndsWith(value, ending)
slice
const value = "ABCDEF...WXYZ" const ending = "Z" compareSliceMethod(value, ending)
hardcoded index
const value = "ABCDEF...WXYZ" const ending = "Z" compareByIndex(value, ending)