[proggeramlug]

Summary

Object.hasOwn (ES2022) worked as a direct call but not as a first-class value: typeof Object.hasOwn folded to "function", yet reading the value produced the 0.0/undefined sentinel — a non-callable. This fixes that, unblocking the next layer of the #3527 Express compile.

Why it matters

The const-alias call-fold (const k = Object.hasOwn; k(o, x)) hid the gap, but iconv-lite's merge-exports.js assigns it through a ternary into a var:

var hasOwn = typeof Object.hasOwn === "undefined"
  ? Function.call.bind(Object.prototype.hasOwnProperty)
  : Object.hasOwn
...
if (hasOwn(module, key)) target[key] = module[key]

The ternary defeats the fold, so hasOwn held a non-callable and hasOwn(module, key) threw TypeError: value is not a function during iconv-lite init — a hard blocker compiling Express. (Localized via a debug-symbol build + b print_uncaught → backtrace pointing at merge-exports.js.)

Fix (two parts)

• Runtime (global_this.rs): reify Object.hasOwn as a callable static on the Object constructor closure (object_hasown_thunk → existing js_object_has_own), alongside the existing keys/values/assign/… thunks. Makes the rebound form (const O = Object; O.hasOwn(o, x)) dispatch correctly.
• Codegen (property_get.rs): when Object.hasOwn is read as a VALUE (PropertyGet { GlobalGet(0), "hasOwn" }), resolve the reified Object constructor closure and read the hasOwn static off it — mirroring the existing Error.captureStackTrace value path — instead of emitting the 0.0 sentinel.

Verification

• typeof Object.hasOwn === "function"; the value computes correctly whether called directly, stored in a var via a ternary, passed through an array, or rebound (const O = Object).
• test_gap_object_methods.ts extended with the as-value cases — byte-identical to node --experimental-strip-types.
• No regression: direct Object.hasOwn(o,k), Object.keys, and typeof Error.isError all still correct. cargo fmt --check clean.
• The Express compile now advances past iconv-lite's merge-exports to the next blocker.

Scope

The broader "Object.keys/values/… as escaping values" gap (a pre-existing known limitation) is unchanged; this fixes the ES2022 hasOwn case that Express's dependency tree actually exercises.

Part of the #3527 chain (prior: #3537/#3543/#3546 codegen, #3551 wildcard, #3733 hasOwnProperty SIGBUS). No version bump / changelog — folded in at merge per the worktree-PR convention.