@matheusbsbs / matheus-bagliano / commits / e4d0c11c04

repack: respect kept objects with '--write-midx -b'

Historically, we needed a single packfile in order to have reachability bitmaps. This introduced logic that when 'git repack' had a '-b' option that we should stop sending the '--honor-pack-keep' option to the 'git pack-objects' child process, ensuring that we create a packfile containing all reachable objects. In the world of multi-pack-index bitmaps, we no longer need to repack all objects into a single pack to have valid bitmaps. Thus, we should continue sending the '--honor-pack-keep' flag to 'git pack-objects'. The fix is very simple: only disable the flag when writing bitmaps but also _not_ writing the multi-pack-index. This opens the door to new repacking strategies that might want to keep some historical set of objects in a stable pack-file while only repacking more recent objects. To test, create a new 'test_subcommand_inexact' helper that is more flexible than 'test_subcommand'. This allows us to look for the --honor-pack-keep flag without over-indexing on the exact set of arguments. Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Derrick Stolee committed Dec 20, 2021 at 14:48 UTC e4d0c11c04ec3c28922168844ae2694e0d015b4e

3 files changed +41 -1

builtin/repack.c

+1 -1

@@ -691,7 +691,7 @@ int cmd_repack(int argc, const char **argv, const char *prefix)

691 write_bitmaps = 0;

692 }

693 if (pack_kept_objects < 0)

694 - pack_kept_objects = write_bitmaps > 0;

694 + pack_kept_objects = write_bitmaps > 0 && !write_midx;

695

696 if (write_bitmaps && !(pack_everything & ALL_INTO_ONE) && !write_midx)

697 die(_(incremental_bitmap_conflict_error));

t/t7700-repack.sh

@@ -372,4 +372,10 @@ test_expect_success '--write-midx with preferred bitmap tips' '

372 )

373 '

374

375 +test_expect_success '--write-midx -b packs non-kept objects' '

376 + GIT_TRACE2_EVENT="$(pwd)/trace.txt" \

377 + git repack --write-midx -a -b &&

378 + test_subcommand_inexact git pack-objects --honor-pack-keep <trace.txt

379 +'

380 +

381 test_done

t/test-lib-functions.sh

+34

@@ -1748,6 +1748,40 @@ test_subcommand () {

1748 fi

1749 }

1750

1751 +# Check that the given command was invoked as part of the

1752 +# trace2-format trace on stdin, but without an exact set of

1753 +# arguments.

1754 +#

1755 +# test_subcommand [!] <command> <args>... < <trace>

1756 +#

1757 +# For example, to look for an invocation of "git pack-objects"

1758 +# with the "--honor-pack-keep" argument, use

1759 +#

1760 +# GIT_TRACE2_EVENT=event.log git repack ... &&

1761 +# test_subcommand git pack-objects --honor-pack-keep <event.log

1762 +#

1763 +# If the first parameter passed is !, this instead checks that

1764 +# the given command was not called.

1765 +#

1766 +test_subcommand_inexact () {

1767 + local negate=

1768 + if test "$1" = "!"

1769 + then

1770 + negate=t

1771 + shift

1772 + fi

1773 +

1774 + local expr=$(printf '"%s".*' "$@")

1775 + expr="${expr%,}"

1776 +

1777 + if test -n "$negate"

1778 + then

1779 + ! grep "\"event\":\"child_start\".*\[$expr\]"

1780 + else

1781 + grep "\"event\":\"child_start\".*\[$expr\]"

1782 + fi

1783 +}

1784 +

1785 # Check that the given command was invoked as part of the

1786 # trace2-format trace on stdin.

1787 #