fix(hir,codegen): route class-extends userland stream-shim ctor through its real constructor (winston)

[proggeramlug]

Problem

Native-compiling winston (corpus compilePackages:[\"*\"]) threw
TypeError: Cannot convert undefined or null to object at
winston/lib/winston/logger.js:695 — const { pipes } = this._readableState
where this._readableState was undefined.

winston's Logger is class Logger extends Transform, and Transform comes
from the readable-stream npm package
(const { Stream, Transform } = require('readable-stream')), NOT node:stream.
readable-stream's hierarchy is Transform → Duplex → Readable wired with ES5
require('inherits')(...); the Readable constructor sets
this._readableState = new ReadableState(...).

Root cause

The native-parent match in lower_class_decl / lower_class_from_ast
(perry-hir/src/lower_decl/class_decl.rs) treated any parent literally
named Readable/Writable/Duplex/Transform as the node:stream builtin,
purely on the textual name. So winston's class Logger extends Transform was
routed to the native js_node_stream_transform_subclass_init shim, which
installs the native stream method surface but never sets _readableState
/_writableState/_transformState. readable-stream's own code then reads
this._readableState.pipes and crashes.

A genuine node:stream import registers the name as the stream native
module (register_native_module(binding, \"stream\", Some(name))); a
readable-stream binding never does (it isn't a node builtin), so the two are
distinguishable.

Fix

• HIR: new is_genuine_node_stream_parent() gate — the four classic
  stream names map to the native node_stream parent only when
  lookup_native_module(name) resolves to the stream module. Otherwise the
  class falls through to the dynamic extends_expr parent path
  (js_register_class_parent_dynamic + js_fetch_or_value_super), which runs
  the package's real constructor chain on the subclass instance.
• Codegen (this_super_call.rs): the stream-family names are only treated
  as built-in parents for super() routing when HIR captured no
  extends_expr; when one was captured (the userland case) defer to the
  dynamic dispatch so the real Transform body runs.

Validation

• cargo fmt --check clean; check_file_size.sh, gc_store_site_inventory.py,
  addr_class_inventory.py all pass; perry-hir tests green.
• Genuine node:stream subclass path unchanged
  (test_read_undefined_proto_getter_promise_ctor.ts matches node).
• New regression fixture test_gap_class_extends_userland_stream_shim.ts
  (ES5 inherits-built Transform → Duplex → Readable, ES6 class extends Transform) matches node byte-for-byte.
• Full corpus 57/59 — no regressions (ws and other stream-using packages
  still green; the other failure, semver, is pre-existing and unrelated).

winston before / after & next wall

• Before: TypeError: Cannot convert undefined or null to object at
  logger.js:695 (this._readableState undefined).

• After: that throw is gone. winston now reaches a deeper,
  distinct cross-module wall:
  TypeError: Cannot set properties of null or undefined (setting 'needReadable')
  at readable-stream/lib/_stream_transform.js:97.

  Investigation of the new wall (probed at runtime): two interacting
  cross-module issues remain, both outside the scope of this stream-routing fix:

  1. Destructured re-export binds the wrong value — readable-stream's
     index does module.exports = require('./_stream_readable.js'); exports.Transform = require('./_stream_transform.js').
     winston's const { Transform } = require('readable-stream') resolves
     Logger's dynamic parent to the Readable function value, not Transform
     (confirmed: Logger's register_parent_dynamic parent bits == Readable's).
  2. util.inherits reached indirectly (require('inherits')(...) /
     var inherits = require('util').inherits; inherits(...)) does not always
     lower to the native js_util_inherits, so the synthetic-class parent chain
     Transform → Duplex → Readable isn't fully registered and the
     if (!(this instanceof Readable)) guard re-news a throwaway object.

  Minimal multi-module repros of both were built and confirm the behavior. A
  speculative runtime mint of the synthetic parent id was prototyped and
  reverted (it did not clear winston and added unvalidated behavioral
  surface).

Notes

Per CONTRIBUTING / CLAUDE.md, this PR does not bump Cargo.toml version, the
Current Version line, CHANGELOG.md, or Cargo.lock — the maintainer folds
those in at merge.

Summary by CodeRabbit

• Bug Fixes
  • Fixed class inheritance handling for userland stream-like implementations. Classes extending custom stream classes (instead of native Node.js streams) now compile correctly.
  • Added distinction between native Node.js stream constructors and userland stream-shim bindings to resolve edge cases in prototype inheritance.

[coderabbitai]

Caution

Review failed

Pull request was closed or merged during review

📝 Walkthrough

Walkthrough

Adds a is_genuine_node_stream_parent helper in HIR class lowering that consults ctx.lookup_native_module to confirm a name like Readable/Writable/Duplex/Transform is actually from the node:stream native module before mapping it to the node_stream native parent. The codegen SuperCall path mirrors this by making the stream-family built-in gate conditional on extends_expr being absent. A new TypeScript test file exercises Logger extends a userland Transform shim.

Changes

Userland stream-shim parent discrimination

Layer / File(s)	Summary
HIR: is_genuine_node_stream_parent helper and call sites crates/perry-hir/src/lower_decl/class_decl.rs	Introduces the private helper is_genuine_node_stream_parent, which returns true only when ctx.lookup_native_module(name) resolves to the "stream" native module. Both lower_class_decl and lower_class_from_ast now gate the ("node_stream", <name>) mapping on this check; non-genuine bindings are no longer mapped to native parents.
Codegen: extends_expr-conditional stream built-in gate crates/perry-codegen/src/expr/this_super_call.rs	In Expr::SuperCall, is_builtin_parent_name for stream-family names (Readable, Writable, Transform, ReadableStream, etc.) is now false when current_class.extends_expr is present, routing those through the dynamic dispatch path. Error/TypeError and is_other_builtin_constructor_name remain unconditional.
Test: Logger extending userland Transform test-files/test_gap_class_extends_userland_stream_shim.ts	Adds a self-contained regression test with ES5-style inherits, minimal Readable/Writable/Duplex/Transform constructor chain, a Logger extends Transform class, and runtime state assertions validating _readableState, _writableState, _transformState, configured, and pipeCount().

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• PerryTS/perry#5095: Directly related — modifies the same class_decl.rs and expr/this_super_call.rs files to fix stream-parent/subclassing handling, forming the baseline this PR builds on.

Poem

🐇 Hoppity-hop through the stream shim maze,
Where Readable names wore a native disguise!
Now lookup_native_module peeks through the haze,
And userland Transform no longer misguides.
extends_expr speaks truth — the gate opens wide,
Winston can log with the right parent inside! 🎉

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main fix: routing userland stream-shim constructors through their real implementation rather than the node:stream native path.
Description check	✅ Passed	The description comprehensively covers the problem, root cause, fix strategy, and validation with clear examples and code references.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/winston-stream-subclass-state

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