Strengthen RecyclerBytesStreamOutputTests#140263
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DaveCTurner merged 1 commit intoelastic:mainfrom Jan 8, 2026
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Today `RecyclerBytesStreamOutputTests` only covers the case where the recycler supplies a buffer with zero offset, potentially missing bugs that only arise with slices of a larger pool of buffers. This commit strengthens these tests to verify the behaviour when using a slice of a larger pool, including verification that we never write outside our buffer and that we do not attempt to read from the buffer after it is released.
DaveCTurner
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Pinging @elastic/es-distributed-coordination (Team:Distributed Coordination) |
DaveCTurner
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Jan 7, 2026
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| // This seems kinda trappy: a recycler doesn't guarantee anything about the contents of the buffers it supplies, and in | ||
| // practice it might contain data left there by the previous user. As used today this is all ok, we always overwrite | ||
| // everything eventually in all production usages, but it seems like it might cause problems at some point. | ||
| // TODO should we wipe these contents when extending the stream with a seek like this just to be on the safe side? | ||
| // In the meantime, for this test only, zero out the buffer contents so that it matches expectedBuffer. |
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NB this bit, should we address this?
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Maybe introduce friends to seek and skip that perform filling, when in doubt? And rename current seek/skip as unsafeSeek saying there might be garbage in between.
mhl-b
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Jan 8, 2026
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+801
| // This seems kinda trappy: a recycler doesn't guarantee anything about the contents of the buffers it supplies, and in | ||
| // practice it might contain data left there by the previous user. As used today this is all ok, we always overwrite | ||
| // everything eventually in all production usages, but it seems like it might cause problems at some point. | ||
| // TODO should we wipe these contents when extending the stream with a seek like this just to be on the safe side? | ||
| // In the meantime, for this test only, zero out the buffer contents so that it matches expectedBuffer. |
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Maybe introduce friends to seek and skip that perform filling, when in doubt? And rename current seek/skip as unsafeSeek saying there might be garbage in between.
DaveCTurner
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2026/01/07/RecyclerBytesStreamOutputTests-picky-recycler
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Today
RecyclerBytesStreamOutputTestsonly covers the case where therecycler supplies a buffer with zero offset, potentially missing bugs
that only arise with slices of a larger pool of buffers.
This commit strengthens these tests to verify the behaviour when using a
slice of a larger pool, including verification that we never write
outside our buffer and that we do not attempt to read from the buffer
after it is released.