Run results for: Replace tests

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/57.0.2987.133 Safari/537.36

Browser: Chrome 57

Operating system: Mac OS X 10.12.4

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
Replace #1	4132870.5 Ops/sec
Replace #2	4161901.2 Ops/sec
Replace #3	3439726.0 Ops/sec
Replace #4	3133697.2 Ops/sec
Replace #5	2071112.9 Ops/sec

Script Preparation code:

function replace(_input, _find, _replace) {
    var start = -1;
    var cursor = 0;
    var inputLength = _input.length;
    var findLength = _find.length;
    var newString = '';
    var buildString = '';
    if (_find.length === 1 && _replace.length === 1) {
        _input = _input.split('');
        while(_input[_input.indexOf(_find)] >= 0) {
            _input[_input.indexOf(_find)] = _replace;
        }
        newString = _input.join('');
    } else {
        for (var i = 0; i < inputLength; i++) {
            if (_input[i] === _find[cursor]) {
                if (start === -1) {
                    start = i;
                }
                if (findLength - 1 === i - start) {
                    newString += _replace;
                    buildString = '';
                    cursor = 0;
                    start = -1;
                } else {
                    buildString += _find[cursor];
                    cursor++;
                }
            } else {
                newString += buildString + _input[i];
                buildString = '';
                cursor = 0;
                start = -1;
            }
        }
    }
    return newString;
}
function replace2(_input, _find, _replace) {
    var start = -1;
    var cursor = 0;
    var inputLength = _input.length;
    var findLength = _find.length;
    var newString = '';
    var buildString = '';
    if (_find.length === 1 && _replace.length === 1) {
        newString = _input.split(_find).join(_replace);
    } else {
        for (var i = 0; i < inputLength; i++) {
            if (_input[i] === _find[cursor]) {
                if (start === -1) {
                    start = i;
                }
                if (findLength - 1 === i - start) {
                    newString += _replace;
                    buildString = '';
                    cursor = 0;
                    start = -1;
                } else {
                    buildString += _find[cursor];
                    cursor++;
                }
            } else {
                newString += buildString + _input[i];
                buildString = '';
                cursor = 0;
                start = -1;
            }
        }
    }
    return newString;
}

Tests:

Replace #1
replace('helle', 'el', 'a');
Replace #2
replace2('helle', 'el', 'a');
Replace #3
'helle'.replace('el', 'a');
Replace #4
'helle'.replace(/el/g, 'a');
Replace #5
'helle'.split('el').join('a');

Run results for: Replace tests

Replace #1

Replace #2

Replace #3

Replace #4

Replace #5