Microsoft/TypeScript

Docs of `charCodeAt` and `codePointAt` are flipped

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#49,561 opened on Jun 15, 2022

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BugDomain: lib.d.tsHelp Wanted

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Description

Bug Report

Docs of charCodeAt and codePointAt are flipped. Described in MDN, the codePointAt returns Unicode code point, and charCodeAt returns UTF16 char code, however in JSDoc string of Typescript they are flipped.

How it is

https://github.com/microsoft/TypeScript/blob/89d05f7131b233c4482aaba5c15ad289f26173b4/lib/lib.es2015.core.d.ts#L401-L408

https://github.com/microsoft/TypeScript/blob/89d05f7131b233c4482aaba5c15ad289f26173b4/lib/lib.es5.d.ts#L404-L408

How it should be

The codePointAt() method returns a non-negative integer that is the Unicode code point value at the given position. Note that this function does not give the nth code point in a string, but the code point starting at the specified string index. Docs

The charCodeAt() method returns an integer between 0 and 65535 representing the UTF-16 code unit at the given index. Docs

Contributor guide

Research direction
Open the referenced files lib/lib.es2015.core.d.ts and lib/lib.es5.d.ts, swap the JSDoc descriptions between charCodeAt and codePointAt methods.
Tech stack
typescript
Domain
documentation
Issue type
Documentation
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
1
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
None
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
95