fix(lower): #6143 — unresolvable object shorthand throws ReferenceError (was silently dropped)

[proggeramlug]

Summary

Fixes #6143. const o = { undeclaredName } must throw ReferenceError: undeclaredName is not defined (a shorthand reads its binding). Perry's object-literal lowering instead did continue, silently dropping the property, in both legacy handlers (non-spread + spread). The closed-shape fast path bails to those on an unresolvable shorthand, so { undeclaredName } produced an empty object.

Fix

Lower the unresolvable shorthand as a normal identifier read (lower_expr(Ident)) — which throws for a truly-undeclared name and reads a sloppy implicit global if one exists.

Validation (vs Node)

Now throw ReferenceError: { a, undeclaredZZZ, b }, { ...{x:1}, undeclaredYYY }, { undeclaredXYZ }.
Unchanged: {a,b} → {"a":1,"b":2}, {a, fn: fn()}, spread {...{a}, b}, sloppy implicit global g=5; {g} → {"g":5}.

Summary by CodeRabbit

• Bug Fixes
  • Object literal shorthand properties that can’t be resolved now behave like normal identifier reads instead of being skipped.
  • In cases with spreads, computed keys, methods, accessors, or prototype setters, undeclared shorthand names now surface a runtime ReferenceError rather than disappearing.
  • The same fix applies to computed-key handling after object initialization, making shorthand behavior more consistent and predictable.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: cf308837-a2ad-4c62-acdc-c181f9109a01

📥 Commits

Reviewing files that changed from the base of the PR and between 74628ed and 32e44bd.

📒 Files selected for processing (1)

• crates/perry-hir/src/lower/expr_object.rs

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📝 Walkthrough

Walkthrough

In object literal lowering, unresolvable shorthand properties in both the spread/IIFE path and the computed-key post-init path now lower to an identifier read via lower_expr instead of being skipped with continue, enabling ReferenceError for undeclared names.

Changes

Object literal shorthand lowering fix

Layer / File(s)	Summary
Lower unresolvable shorthand as identifier read crates/perry-hir/src/lower/expr_object.rs	Both the spread/IIFE shorthand path and the computed-key post-init shorthand path now lower unresolvable shorthand properties via lower_expr on an Ident expression instead of using continue to drop them, producing a ReferenceError for truly undeclared names.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Possibly related PRs

• PerryTS/perry#5244: Both PRs modify the same object-literal shorthand handling in crates/perry-hir/src/lower/expr_object.rs, changing dropped shorthand properties to be lowered/resolved via lower_expr.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main fix for unresolvable object shorthand lowering.
Description check	✅ Passed	The description includes a summary, fix details, and validation, and is mostly aligned with the required template.
Linked Issues check	✅ Passed	The change matches #6143 by lowering unresolvable shorthands as identifier reads in both legacy object-literal paths.
Out of Scope Changes check	✅ Passed	The summary shows only the targeted object-literal lowering fix with no unrelated scope added.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ 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/6142-shorthand-ref.error

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