TrustedRandomAaccess specialization composes incorrectly for nested iter::Zips #80670
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I found this while working on improvements for TRA.
After partially consuming a Zip adapter and then wrapping it into another Zip where the adapters use their
TrustedRandomAccess
specializations leads to the outer adapter returning elements which should have already been consumed.If the optimizer gets tripped up by the addition this might affect performance for chained
zip()
iterators even when the inner one is not partially advanced but it would require more extensive fixes toTrustedRandomAccess
to communicate those offsets earlier.Included test fails on nightly, playground link