Fix unchecked exception in Bun.plugin when target toString throws

[robobun]

What does this PR do?

Fixes an assertNoException() failure in setupBunPlugin found by Fuzzilli (fingerprint e094de1fac1a5ee5).

When Bun.plugin({ target, setup }) is called with a target value whose string coercion throws (e.g. an object with a throwing toString), toStringOrNull returns nullptr and leaves the exception pending. The code then fell through to constructEmptyObject, which asserts that no exception is pending.

Bun.plugin({
  setup: () => {},
  target: { toString() { throw new Error("boom"); } },
});

Before: ASSERTION FAILED: !exception() in debug builds.
After: the thrown error is propagated to the caller.

How did you verify your code works?

• Reproduced the assertion with the fuzzer output and a minimized repro on the debug+ASAN build.
• After the fix, both reproduce cleanly as a thrown JS error.
• Added a regression test to test/js/bun/plugin/plugins.test.ts.

[robobun]

^{Updated 4:28 PM PT - May 20th, 2026}

❌ @robobun, your commit 9ec2e27 has 9 failures in Build #56479 (All Failures):

• src/spawn/process.rs - unused variable: `jc` on :freebsd: aarch64 - build-rust
• src/spawn/process.rs - unused variable: `jc` on :freebsd: x64 - build-rust
• src/spawn/process.rs - unused import: `bun_core::Global` on :freebsd: aarch64 - build-rust
• src/spawn/process.rs - unused import: `bun_core::Global` on :freebsd: x64 - build-rust
• src/spawn_sys/spawn_process.rs - variable does not need to be mutable on :freebsd: aarch64 - build-rust
• src/spawn_sys/spawn_process.rs - variable does not need to be mutable on :freebsd: x64 - build-rust
• src/threading/Futex.rs - unreachable `pub` item on :freebsd: aarch64 - build-rust
• src/threading/Futex.rs - unreachable `pub` item on :freebsd: aarch64 - build-rust
• src/threading/Futex.rs - unreachable `pub` item on :freebsd: x64 - build-rust
• src/threading/Futex.rs - unreachable `pub` item on :freebsd: x64 - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/runtime/server/mod.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/runtime/api/bun/h2_frame_parser.rs - use of deprecated method `bun_collections::HiveArrayFallback::::try_get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on 🐧 x64-asan - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on 🍎 x64 - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on 🐧 aarch64-android - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on :freebsd: aarch64 - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on 🐧 x64-android - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on 🐧 aarch64-musl - build-rust
• src/bundler/LinkerContext.rs - hiding a lifetime that's elided elsewhere is confusing on :freebsd: x64 - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on 🐧 x64-asan - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on 🐧 x64-asan - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on 🍎 x64 - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on 🐧 x64-asan - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on 🍎 x64 - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on 🍎 x64 - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on 🐧 aarch64-android - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on 🐧 aarch64-android - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on 🐧 aarch64-android - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on :freebsd: aarch64 - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on :freebsd: aarch64 - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on :freebsd: aarch64 - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on 🐧 x64-android - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on 🐧 x64-android - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on 🐧 x64-android - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on 🐧 aarch64-musl - build-rust
• src/parsers/lib.rs - feature `allocator_api` is declared but not used on :freebsd: x64 - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on 🐧 aarch64-musl - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on 🐧 aarch64-musl - build-rust
• src/js_parser/lib.rs - feature `allocator_api` is declared but not used on :freebsd: x64 - build-rust
• src/jsc/lib.rs - feature `allocator_api` is declared but not used on :freebsd: x64 - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-asan - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🍎 x64 - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-android - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: aarch64 - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 x64-android - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/js_printer/renamer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on 🐧 aarch64-musl - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/install/PackageManager/PackageManagerEnqueue.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/install/PackageManager/runTasks.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/runtime/server/server_body.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• src/runtime/bake/DevServer.rs - use of deprecated method `bun_collections::HiveArrayFallback::::get`: returns *mut T to uninitialized memory; use get_init / emplace / claim on :freebsd: x64 - build-rust
• linker stderr: clang++: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] on 🐧 x64-asan - build-rust
• linker stderr: clang++: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] on 🐧 aarch64-android - build-rust
• linker stderr: clang++: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] on :freebsd: aarch64 - build-rust
• linker stderr: clang++: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] on 🐧 x64-android - build-rust
• linker stderr: clang++: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] on 🐧 aarch64-musl - build-rust
• linker stderr: clang++: argument unused during compilation: '-no-pie' [-Wunused-command-line-argument] on :freebsd: x64 - build-rust

---

🧪   To try this PR locally:

bunx bun-pr 31151

That installs a local version of the PR into your bun-31151 executable, so you can run:

bun-31151 --bun

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Reviewing files that changed from the base of the PR and between a43a01b and 9ec2e27.

📒 Files selected for processing (2)

• src/jsc/bindings/BunPlugin.cpp
• test/js/bun/plugin/plugins.test.ts

---

Walkthrough

This PR hardens exception handling during Bun plugin target validation. Two RETURN_IF_EXCEPTION guards are added to setupBunPlugin to detect and propagate exceptions during target parsing, and a test verifies that exceptions thrown from invalid target values are correctly forwarded to the caller.

Changes

Plugin Target Exception Handling

Layer / File(s)	Summary
Target validation exception guards and test src/jsc/bindings/BunPlugin.cpp, test/js/bun/plugin/plugins.test.ts	Exception handling is tightened in setupBunPlugin target parsing with RETURN_IF_EXCEPTION guards after targetString extraction and validation. A test verifies that exceptions thrown from target.toString() are propagated correctly when an invalid target is provided to plugin().

🚥 Pre-merge checks | ✅ 4

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main fix: handling unchecked exceptions in Bun.plugin when target toString throws.
Description check	✅ Passed	The description covers both required sections with clear explanation of the problem, code example, and verification method including test addition.
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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[github-actions]

This PR may be a duplicate of:

1. Fix unchecked exception when Bun.plugin target coercion throws #31017 - Adds the same two RETURN_IF_EXCEPTION guards in setupBunPlugin in BunPlugin.cpp to fix the unchecked exception when target.toString() throws
2. Handle exceptions from toStringOrNull in Bun.plugin target parsing #28369 - Adds the identical RETURN_IF_EXCEPTION guards in setupBunPlugin for the same crash path where a throwing Symbol.toPrimitive on target leaves a pending exception before constructEmptyObject

🤖 Generated with Claude Code

[robobun]

Duplicate of #31017 (and #28369). Closing in favor of the existing PR.

[claude]

LGTM — straightforward RETURN_IF_EXCEPTION guard for a fuzzer-found unchecked exception, with a regression test.

Extended reasoning...

Overview

This PR adds two RETURN_IF_EXCEPTION(throwScope, {}) checks in setupBunPlugin (src/jsc/bindings/BunPlugin.cpp) so that an exception thrown during target string coercion (toStringOrNull / JSString::value) is propagated instead of falling through to constructEmptyObject, which asserts no pending exception. A regression test in test/js/bun/plugin/plugins.test.ts exercises a target whose toString throws and asserts the error surfaces.

Security risks

None. This is purely an exception-propagation correctness fix in argument validation; no auth, crypto, permissions, or untrusted-input parsing changes. If anything it hardens behavior by failing fast on a pending exception rather than continuing in an inconsistent VM state.

Level of scrutiny

Low. The change is two lines of the canonical JSC idiom (RETURN_IF_EXCEPTION after a fallible operation) already used dozens of times in this same file. Placement is correct: the outer check covers toStringOrNull returning nullptr with a pending exception, and the inner check covers value(globalObject) (rope resolution can OOM). No control-flow or semantic changes beyond early-returning the existing exception.

Other factors

• Fuzzer-reported assertion failure with a clear minimized repro in the PR description.
• Regression test added next to the existing "handles invalid 'target'" test, following the same pattern.
• Bug-hunting system found no issues.
• No CODEOWNERS coverage for this path and no outstanding reviewer comments.