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From:   Junio C Hamano <gitster@pobox.com>
To:     Taylor Blau <me@ttaylorr.com>
Cc:     Jonathan Tan <jonathantanmy@google.com>, git@vger.kernel.org,
        Derrick Stolee <derrickstolee@github.com>
Subject: Re: [PATCH v6 0/7] Changed path filter hash fix and version bump
In-Reply-To: <xmqqzg3ib2ma.fsf@gitster.g> (Junio C. Hamano's message of "Wed,
        26 Jul 2023 17:49:01 -0700")
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        <xmqq8rb2csr1.fsf@gitster.g> <ZMG3kEO0BzKPaG75@nand.local>
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Junio C Hamano <gitster@pobox.com> writes:

> ...  How hard it would be to construct a test
> case that fails if filter computed as v1 is marketed as v2?

There may be a more effective way for future-proofing, besides
ensuring the test coverage.

Although this series added a way to see which version the on-disk
data is using using the version field, I do not think it touched the
"struct bloom_filter" and "struct bloom_key" that represent the
in-core data.  If we had a member in these structures that
get_or_compute_bloom_filter() can fill in from the on-disk structure
or the version it used when it computed the filter anew, would it
become easier to catch the case where we try to add a version 2
computed key to a filter that was read from version 1 on-disk
structure, presumably at add_key_to_filter()?

Thanks.