Run results for: Split Join vs Basic string replace

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.1.2 Safari/605.1.15

Browser: Safari 14

Operating system: Mac OS X 10.14.6

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Replace (SIMPLE)	2295042.0 Ops/sec
Split and Join	211251.2 Ops/sec
Replace (REGEX)	31465.0 Ops/sec

Script Preparation code:

var str = 'Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxyAbcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy Abcd efghij klmnopqrstuv wxy';

Tests:

Replace (SIMPLE)
str.replace("m", "$&Z");
Split and Join
str.split('').join('Z') + 'Z';
Replace (REGEX)
str.replace(/./g, "$&Z");

Run results for: Split Join vs Basic string replace

Replace (SIMPLE)

Split and Join

Replace (REGEX)