git/t/t6115-rev-list-du.sh
Taylor Blau 7b3c8e9f38 pack-bitmap: drop --unpacked non-commit objects from results
When performing revision queries with `--objects` and
`--use-bitmap-index`, the output may incorrectly contain objects which
are packed, even when the `--unpacked` option is given. This affects
traversals, but also other querying operations, like `--count`,
`--disk-usage`, etc.

Like in the previous commit, the fix is to exclude those objects from
the result set before they are shown to the user (or, in this case,
before the bitmap containing the result of the traversal is enumerated
and its objects listed).

This is performed by a new function in pack-bitmap.c, called
`filter_packed_objects_from_bitmap()`. Note that we do not have to
inspect individual bits in the result bitmap, since we know that the
first N (where N is the number of objects in the bitmap's pack/MIDX)
bits correspond to objects which packed by definition.

In other words, for an object to have a bitmap position (not in the
extended index), it must appear in either the bitmap's pack or one of
the packs in its MIDX.

This presents an appealing optimization to us, which is that we can
simply memset() the corresponding number of `eword_t`'s to zero,
provided that we handle any objects which spill into the next word (but
don't occupy all 64 bits of the word itself).

We only have to handle objects in the bitmap's extended index. These
objects may (or may not) appear in one or more pack(s). Since these
objects are known to not appear in either the bitmap's MIDX or pack,
they may be stored as loose, appear in other pack(s), or both.

Before returning a bitmap containing the result of the traversal back to
the caller, drop any bits from the extended index which appear in one or
more packs. This implements the correct behavior for rev-list operations
which use the bitmap index to compute their result.

Co-authored-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-11-07 11:23:52 +09:00

80 lines
2.3 KiB
Bash
Executable file

#!/bin/sh
test_description='basic tests of rev-list --disk-usage'
. ./test-lib.sh
# we want a mix of reachable and unreachable, as well as
# objects in the bitmapped pack and some outside of it
test_expect_success 'set up repository' '
test_commit --no-tag one &&
test_commit --no-tag two &&
git repack -adb &&
git reset --hard HEAD^ &&
test_commit --no-tag three &&
test_commit --no-tag four &&
git reset --hard HEAD^
'
# We don't want to hardcode sizes, because they depend on the exact details of
# packing, zlib, etc. We'll assume that the regular rev-list and cat-file
# machinery works and compare the --disk-usage output to that.
disk_usage_slow () {
git rev-list --no-object-names "$@" |
git cat-file --batch-check="%(objectsize:disk)" |
perl -lne '$total += $_; END { print $total}'
}
# check behavior with given rev-list options; note that
# whitespace is not preserved in args
check_du () {
args=$*
test_expect_success "generate expected size ($args)" "
disk_usage_slow $args >expect
"
test_expect_success "rev-list --disk-usage without bitmaps ($args)" "
git rev-list --disk-usage $args >actual &&
test_cmp expect actual
"
test_expect_success "rev-list --disk-usage with bitmaps ($args)" "
git rev-list --disk-usage --use-bitmap-index $args >actual &&
test_cmp expect actual
"
}
check_du HEAD
check_du --objects HEAD
check_du --objects HEAD^..HEAD
test_expect_success 'setup for --unpacked tests' '
git repack -adb &&
test_commit unpacked
'
check_du --all --objects --unpacked
# As mentioned above, don't use hardcode sizes as actual size, but use the
# output from git cat-file.
test_expect_success 'rev-list --disk-usage=human' '
git rev-list --objects HEAD --disk-usage=human >actual &&
disk_usage_slow --objects HEAD >actual_size &&
grep "$(cat actual_size) bytes" actual
'
test_expect_success 'rev-list --disk-usage=human with bitmaps' '
git rev-list --objects HEAD --use-bitmap-index --disk-usage=human >actual &&
disk_usage_slow --objects HEAD >actual_size &&
grep "$(cat actual_size) bytes" actual
'
test_expect_success 'rev-list use --disk-usage unproperly' '
test_must_fail git rev-list --objects HEAD --disk-usage=typo 2>err &&
cat >expect <<-\EOF &&
fatal: invalid value for '\''--disk-usage=<format>'\'': '\''typo'\'', the only allowed format is '\''human'\''
EOF
test_cmp err expect
'
test_done