DSA.04.03 JuniorCore — asked often

Sorting in JavaScript

Comes up in: DSA, JavaScript, Recruiter screen

This concept is being written. It gets the full five steps — explanation, predict, interview angle, practice with tests, and review cards. Here is exactly what it will cover, so you can study it elsewhere in the meantime.

What it covers

Array.prototype.sort is stable (required since ES2019)
V8 uses TimSort (since V8 7.0)
default sort compares strings
comparator contract (negative/zero/positive, consistent)
sorting objects by multiple keys
toSorted
localeCompare/Intl.Collator

Words you will know

TimSortcomparator contract

What you will practise

multi-key sort
fix 4 comparator bugs

Interview questions this answers

What does it mean for a sort to be stable? Is JavaScript's sort stable?