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Elior Nataf LackritzandGitHub
e14f4277dc
`Command(resume=..., update=...)` applied its update twice once the
resumed node called `interrupt()` again, with sync or async durability
(`invoke`'s default). A node that asks three times, resumed with
`Command(resume=str(i), update={"log": [f"u{i}"]})`, ends with `["u1",
"u1", "u2", "u3", "a:123"]`.
## Cause
The null task's writes are saved as one list, and savers key a regular
write by its position in that list. The Command's resume came first, so
its update was stored at index 1. The next Command saved the null task's
earlier writes again without the resume, which put the update at index
0, so it was stored twice and every later resume applied both copies.
`durability="exit"` saves after the resume is consumed, so it wasn't
affected.
## Fix
The null task's special writes (a resume) now go after its regular ones,
so each regular write keeps its index as the list grows.
`test_resume_with_update_applies_the_update_once` fails on `main` for
sync and async durability.
Found by @hntrl, and flagged by @soarez on #9314.