Microsoft/TypeScript

`@deprecated` incorrectly marks the wrong type as deprecated when used in JavaScript.

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#47,652 opened on Jan 28, 2022

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 (5 comments) (0 reactions) (0 assignees)TypeScript (6,726 forks)batch import
BugDomain: JSDocHelp Wanted

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Description

Bug Report

🔎 Search Terms

deprecated jsdoc js

🕗 Version & Regression Information

  • This is the behavior in every version I tried, and I reviewed the FAQ for entries about deprecated

⏯ Playground Link

Playground (JavaScript) Playground (TypeScript)

💻 Code

/**
 * @deprecated
 * @typedef {number | string} MyType
 */

class Foo {
    /**
     * @param {MyType} x
     *         ^^^^^^-- Not marked as deprecated
     */
    foo(x) {

    }
}

const x = new Foo();
//            ^^^--- Marked as deprecated
x.foo(5);

🙁 Actual behavior

The class Foo is marked as deprecated.

🙂 Expected behavior

The type MyType of parameter x of Foo.foo() should be marked as deprecated and the class Foo should not. Just like how it works in the TypeScript equivalent of this code.

Contributor guide

Research direction
Examine the TypeScript checker's deprecation logic for JSDoc typedefs in JavaScript files. The bug indicates that deprecation is incorrectly applying to the class instead of the parameter type. Focus on the checker's handling of `@deprecated` on type aliases and how it affects subsequent usage.
Tech stack
typescriptjavascript
Domain
developer experience
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
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
TypeScriptJavaScriptGit
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70