Run results for: Trimming leading/trailing characters again

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36 Edg/120.0.0.0

Browser: Chrome 120

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Index Version (Jason Larke)

992K/s

Split Version (CheapSk8)

263K/s

Substring Version (Pho3niX83)

237K/s

Boolean Filter Version (mbaer3000)

155K/s

Regex Version (leaf)

132K/s

Spread Version (Robin F.)

972/s

View exact numbers

Test name	Executions per second
✓ Index Version (Jason Larke)	991,833 Ops/sec
Split Version (CheapSk8)	262,915 Ops/sec
Substring Version (Pho3niX83)	237,049 Ops/sec
Boolean Filter Version (mbaer3000)	155,216 Ops/sec
Regex Version (leaf)	131,508 Ops/sec
Spread Version (Robin F.)	972 Ops/sec

Script Preparation code:

var TestString = '+'.repeat(200) + '='.repeat(20000) + '+'.repeat(200);

var regexTrim = function(str, ch) {
    if (ch === ']') ch = '\\]';
    else if (ch === '^') ch = '\\^';
    else if (ch === '\\') ch = '\\\\';
    return str.replace(new RegExp('^[' + ch + ']+|[' + ch + ']+$', 'g'), '');
};

function indexTrim(str, ch) {
    var start = 0, 
        end = str.length;

    while(start < end && str[start] === ch)
        ++start;

    while(end > start && str[end - 1] === ch)
        --end;

    return (start > 0 || end < str.length) ? str.substring(start, end) : str;
}

function booleanTrim(str, ch) {
    return str.split(ch).filter(Boolean).join(ch);
}

function spreadTrim(str, ch) {
    const first = [...str].findIndex(char => char !== ch);
    const last = [...str].reverse().findIndex(char => char !== ch);
    return str.substring(first, str.length - last);
}

function substringTrim(str, ch) {
    while(str.charAt(0)==ch) {
        str = str.substring(1);
    }

    while(str.charAt(str.length-1)==ch) {
        str = str.substring(0,str.length-1);
    }

    return str;
}

function splitTrim(str, ch) {
   let res = str.split(ch);
   return res.length > 1 ? res[1] : res[0];
}

Tests:

Index Version (Jason Larke)
indexTrim(TestString, '+');
Regex Version (leaf)
regexTrim(TestString, '+')
Boolean Filter Version (mbaer3000)
booleanTrim(TestString, '+')
Spread Version (Robin F.)
spreadTrim(TestString, '+')
Substring Version (Pho3niX83)
substringTrim(TestString, '+')
Split Version (CheapSk8)
splitTrim(TestString, '+')