The punycode deprecation trace is not useful

[glenjamin]

Version

v24.13.1

Platform

Darwin <hostname> 24.6.0 Darwin Kernel Version 24.6.0: Wed Nov  5 21:34:00 PST 2025; root:xnu-11417.140.69.705.2~1/RELEASE_ARM64_T8132 arm64

Subsystem

No response

What steps will reproduce the bug?

In a project that uses punycode somewhere.

NODE_OPTIONS='--trace-deprecation' npm t

or more concretely (although obviously in this case it's trivial to identify the source):

npm init -y
npm i psl@1.8.0
node --trace-deprecation -e 'require("psl")'

How often does it reproduce? Is there a required condition?

always

What is the expected behavior? Why is that the expected behavior?

I would expect a trace telling me which package/file is requiring punycode

What do you see instead?

What I actually get is

(node:49440) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
    at node:punycode:7:10
    at BuiltinModule.compileForInternalLoader (node:internal/bootstrap/realm:398:7)
    at BuiltinModule.compileForPublicLoader (node:internal/bootstrap/realm:337:10)
    at loadBuiltinModule (node:internal/modules/helpers:125:7)
    at loadBuiltinWithHooks (node:internal/modules/cjs/loader:1195:15)
    at Module._load (node:internal/modules/cjs/loader:1285:48)
    at TracingChannel.traceSync (node:diagnostics_channel:328:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:245:24)
    at Module.require (node:internal/modules/cjs/loader:1548:12)
    at require (node:internal/modules/helpers:152:16)

Additional information

I note that #56632 will reduce the number of times this warning appears, so perhaps that's good enough - but in general it seems reasonable to say that using --trace-deprecation should actually trace the usage of deprecated code.

[MikeMcC399]

This appears to be a regression introduced through #60991 in v24.13.1. I checked on several other key Node.js versions, and none of them triggered using psl@1.8.0. (The issue was actually fixed in psl@1.10.0.)

Node.js	Result
20.20.0	no deprecation
22.22.0	no deprecation
24.0.0	no deprecation
24.13.0	no deprecation
24.13.1	at node:punycode:7:10
25.6.1	no deprecation

Also there is a documentation mismatch, where DEP00040 is declared as a Runtime deprecation (all code). The v24.13.1 code however attempts to apply an Application deprecation (non-node_modules code only). Edit: submitted #61916 to update the documentation.

node/lib/punycode.js

Lines 6 to 13 in a087002

	if (!isInsideNodeModules()) {
	process.emitWarning(
	'The `punycode` module is deprecated. Please use a userland ' +
	'alternative instead.',
	'DeprecationWarning',
	'DEP0040',
	);
	}

---

#61724 appears also to be related to changes introduced in #60991

[MikeMcC399]

I'm also seeing this issue with https://github.com/eslint/eslint/docs and Node.js 24.13.1.