January 7, 2026
Schrödinger’s payload
Investigating and fixing a nasty clone bug
Ghost payload spooks devs; debate over ‘easy copy’ plan explodes
TLDR: A merge bot’s update sometimes arrived empty and the investigation touched the controversial push for easier, automatic copying in Rust. Commenters split between fearing “magic clones” that hide bugs and wanting safer defaults, with extra drama over testing methods—important because silent data loss wrecks automation everyone relies on.
A developer trying to ship a merge bot found their update request randomly arriving with no message body—basically an empty envelope. Cue the comments turning into CSI: GitHub. Memes flew (“404 Body Not Found”), theories stacked (“Who ate the payload?”), and when the write‑up hinted the culprit touches the hotly discussed Rust “Ergonomic Cloning” plan—making copying objects more automatic—the crowd went full courtroom. Some saw it as Exhibit A that “easy copy” risks hiding nasty surprises; others said this proves we need gentler, safer defaults to stop developers from juggling sharp knives.
What’s an HTTP “PATCH”? It’s like sending a partial update, and this one mysteriously lost its contents mid-flight. The thread split hard: anti‑magic folks warned that automatic clones can mask where data actually goes; pro‑ergonomics folks argued it prevents exactly these footguns. The testing crowd piled in too—“integration tests for the win,” since spinning up the whole app caught a ghost no unit test would. Meanwhile, blame ping‑ponged between the mocking tool and the GitHub client, with spicy shots at both. Through the chaos, everyone agreed on one thing: invisible payloads are the scariest kind. The fix brings the bot closer to production, but the cloning culture war is just heating up.
Key Points
- •Integration tests for bors use a full web app setup with live Postgres and mocked GitHub endpoints via wiremock.
- •During refactoring, some tests failed due to a mocked PATCH endpoint receiving an empty request body intermittently.
- •The receiving code attempted to deserialize a SetRefRequest (sha field) but panicked when body_json was empty.
- •On the sender side, bors uses octocrab to send PATCH requests with a JSON body including sha and force, suggesting the body should be present.
- •After verifying local code, the author began investigating wiremock and notes the bug’s cause relates to Rust’s Ergonomic cloning initiative.