Benchmark: duplicates in string

Tests:

map: indexOf==lastIndexOf
function duplicateEncode(word) { const chars = word.toLowerCase(); return chars .split("") .map((char) => { if (chars.indexOf(char) === chars.lastIndexOf(char)) { return "("; } else return ")"; }) .join(""); } duplicateEncode("Lorem ipsum dolor, sit amet consectetur adipisicing elit. Consectetur iste corrupti aperiam omnis perferendis eum quidem quo necessitatibus natus! Eveniet reiciendis est reprehenderit quo ullam praesentium amet aperiam veniam illo!")
charMap
function duplicateEncode(word) { const chars = word.toLowerCase().split(""); const charMap = {}; chars.forEach((char) => { char in charMap ? charMap[char]++ : (charMap[char] = 1); }); let result = ""; chars.forEach((char) => { charMap[char] > 1 ? (result += ")") : (result += "("); }); return result; } duplicateEncode("Lorem ipsum dolor, sit amet consectetur adipisicing elit. Consectetur iste corrupti aperiam omnis perferendis eum quidem quo necessitatibus natus! Eveniet reiciendis est reprehenderit quo ullam praesentium amet aperiam veniam illo!")

Rendered benchmark preparation results:

Previous results

Test case name	Result
map: indexOf==lastIndexOf
charMap

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36 Edg/107.0.1418.42

Browser/OS: Chrome 107 on Mac OS X 10.15.7

Test name	Executions per second
map: indexOf==lastIndexOf	92872.8 Ops/sec
charMap	122273.9 Ops/sec

duplicates in string (version: 1)