[jasnell]

Fixup patched then handling in consumer methods

[clanky-the-clanker]

💬 Approved with comments — The code change is correct and well tested. The only finding is a documentation WARNING: the new AGENTS.md invariant covers more than the code guarantees.

Findings: 1 warning

_{The decision is advisory: this comment never approves, blocks or requests changes on the pull request.}

🔧 Fix with your agent

Paste the following into your coding agent to investigate and fix these issues.

Fix the following code review issues found in pull request #8060.

Before making changes, review each issue and present a brief summary table:
- For each finding, state whether you agree, disagree, or need clarification
- If you disagree (e.g., the fix would require disproportionate changes
  for minimal ROI, or the finding is factually incorrect), explain why
- If you need to clarify something before deciding, ask those questions
- Then share your plan for which issues to tackle and in what order

## WARNING (1)

### [Documentation] The invariant says every promise the C++ bridge awaits resolves with a primitive, `undefined` or a null-prototype record. But the `ReadableStream.from()` bridge (`js-readable-stream.c++:672-681`) awaits promises yielded by the user's generator, which can resolve to ordinary objects. Limit the rule to body consumption.
- **File:** src/per_isolate/webstreams/AGENTS.md:166

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📝 Documentation: ⚠️ 1 warning

The new promise-settlement invariant covers more than the code guarantees.

Recommendation: 📝 Minor Comments

• [WARNING] The invariant says every promise the C++ bridge awaits resolves with a primitive, undefined or a null-prototype record. But the ReadableStream.from() bridge (js-readable-stream.c++:672-681) awaits promises yielded by the user's generator, which can resolve to ordinary objects. Limit the rule to body consumption. (src/per_isolate/webstreams/AGENTS.md:166)

View full review

src/per_isolate/webstreams/AGENTS.md:166-170 says that every promise the C++ bridge awaits resolves with a primitive, undefined or a null-prototype record. That is not true for the whole bridge. The C++ ReadableStream.from() path (src/workerd/api/js-readable-stream.c++:672-681) awaits promises yielded by a user generator through js.toPromise(...).then(...), and those can resolve to ordinary objects. Limit the statement to the body-consumption bridge, so readers don't conclude that yielded values also avoid the then lookup.

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✅ All other checks passed

🔒 Security: ✅ LGTM

No security concerns. Taking user-patched then lookups out of the internal consumption steps makes it harder for user code to interfere with the runtime's internals.

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📖 AGENTS.md: ✅ LGTM

The AGENTS.md updates match the new consumption path and its test guards.

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📋 Code Quality: ✅ LGTM

All body consumers now go through consumeReadableStreamAsArrayBufferRecord, and C++ builds each result (ArrayBuffer, Uint8Array, Blob, text, parsed JSON) from the { buffer } record. BOM handling and UTF-8 decoding live in getReadableStreamText, which json() reuses. The unused TypeScript consumers are removed, and the C++ side no longer dispatches to them. The C++ and JS tests cover all five consumers.

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⚡ Performance: ✅ LGTM

No performance concerns.

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_{Reviewed commit: a518a391 — same changes as 8180d414, so this is that commit's review (no new review was run; line numbers are as of 8180d414)}

[ask-bonk]

Since last review: 0 resolved, 0 still open, 0 new.
LGTM!

Not re-run: tests, docs, api-compat, compat-flags, design-simplicity, jsg-gc, kj-style, memory-safety (no author changes in their files since the last review)

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_{Reviewed commit: a518a391 · github run}

[github-actions]

The generated output of @cloudflare/workers-types matches the snapshot in types/generated-snapshot 🎉