class X extends Stream (the bare node:stream base) throws 'is not a constructor' — #10649 covers only Readable/Writable/Duplex/Transform; blocks nodemailer #10798

class X extends Stream — the bare node:stream base, not one of its subclasses — throws TypeError: is not a constructor. This blocks nodemailer, where class XOAuth2 extends Stream is loaded unconditionally on import.

Found by the package-compilability probe on origin/main (v0.5.1617), nodemailer 9.0.3.

Why it is a gap rather than an oversight

PR #10649 fixed bound-export heritage dispatch for Readable, Writable, Duplex and Transform — its runtime arm matches exactly those four names:

if normalize_native_module_alias(module.as_str()) == "stream" {
    match method.as_str() {
        "Readable" | "Writable" | "Duplex" | "Transform" => ...

Stream (the legacy base class that Readable and friends themselves derive from) is not in that list, so it falls through to the ordinary-call dispatch and never installs. This was predicted from reading #10649's match list against a static scan of nodemailer's heritage sites, and the probe confirmed it.

It is a small surface — one real site across the packages scanned — but it is on nodemailer's import path, so it is fatal rather than partial: the package cannot be loaded at all.

Relationship to the other two stream-heritage gaps

There are now three distinct holes in native stream subclassing, worth tracking together even if fixed separately:

Stream may be the cheapest of the three: unlike PassThrough (where the hidden _transform field is never pre-seeded, so adding a dispatch arm alone provably changes nothing), Stream is a real constructor with a real prototype, so it may only need adding to #10649's match list plus whatever js_node_stream_*_subclass_init equivalent applies. That should be verified rather than assumed — #10745 is precisely the case where the obvious one-line fix was confirmed not to work.

Reproduction

const { Stream } = require('stream');
class Tap extends Stream {}
new Tap();   // TypeError: is not a constructor

Also reachable via import nodemailer from "nodemailer" with the binding removed — it throws on import, before any API is called.