Microsoft/TypeScript

cloneNode should return sub type, not Node

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#283 opened on Jul 28, 2014

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 (25 comments) (63 reactions) (0 assignees)TypeScript (48,455 stars) (6,726 forks)batch import
BugDomain: lib.d.tsHelp Wanted

Description

When I do someElement.cloneNode(), I want the returned element to be the same type as someElement, but right now it's returning type Node.

Contributor guide

Tech stack
typescript
Domain
frontenddeveloper experience
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
TypeScript genericsDOM API knowledge
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65
Research direction
The issue is in the TypeScript DOM type definitions, likely in lib.dom.d.ts. The fix involves making cloneNode generic so that it returns the subtype. Check the issue comments for proposed solutions and consider using overloads or conditional types. No linked PRs exist, so this is a fresh opportunity for a first time contributor.