[PATCH 1/2] t3305: check notes fanout more carefully and robustly
- From
Johan Herland <johan@herland.net>
- Date
- Feb 3, 2020, 21:04 UTC
- Message-ID
- <20200203210445.2854-1-johan@herland.net>
In short, before this patch, this test script: - creates many notes - verifies that all notes in the notes tree has a fanout of 1 - removes most notes - verifies that the notes in the notes tree now has a fanout of 0
The fanout verification only happened twice: after creating all the notes, and after removing most of them.
This patch strengthens the test by checking the fanout after _each_ added/removed note: We assert that the switch from fanout 0 -> 1 happens exactly once while adding notes (and that the switch pervades the entire notes tree). Likewise, we assert that the switch from fanout 1 -> 0 happens exactly once while removing notes.
Additionally, we decrease the number of notes left after removal, from 50 to 15 notes, in order to ensure that fanout 1 -> 0 transition keeps happening regardless of external factors[1].
[1]: Currently (with the SHA1 hash function and the deterministic object ids of the test environment) the fanout heuristic in the notes code happens to switch from 0 -> 1 at 109 notes, and from 1 -> 0 at 59 notes. However, changing the hash function or other external factors will vary these numbers, and the latter may - in theory - go as low as 15. For more details, please see the discussion at https://public-inbox.org/git/20200125230035.136348-4-sandals@crustytoothpaste.net/
Cc: Johannes Schindelin <Johannes.Schindelin@gmx.de> Cc: Brian M. Carlson <sandals@crustytoothpaste.net> Signed-off-by: Johan Herland <johan@herland.net> --- t/t3305-notes-fanout.sh | 101 ++++++++++++++++++++++++++++++---------- 1 file changed, 76 insertions(+), 25 deletions(-)
diff --git a/t/t3305-notes-fanout.sh b/t/t3305-notes-fanout.sh index 831f83d211..402057c83a 100755 --- a/t/t3305-notes-fanout.sh +++ b/t/t3305-notes-fanout.sh @@ -4,6 +4,32 @@ test_description='Test that adding/removing many notes triggers automatic fanout . ./test-lib.sh +path_has_fanout() { + path=$1 && + fanout=$2 && + after_last_slash=$((40 - $fanout * 2)) && + echo $path | grep -q "^\([0-9a-f]\{2\}/\)\{$fanout\}[0-9a-f]\{$after_last_slash\}$" +} + +touched_one_note_with_fanout() { + notes_commit=$1 && + modification=$2 && # 'A' for addition, 'D' for deletion + fanout=$3 && + diff=$(git diff-tree --no-commit-id --name-status --root -r $notes_commit) && + path=$(echo $diff | sed -e "s/^$modification[\t ]//") && + path_has_fanout "$path" $fanout; +} + +all_notes_have_fanout() { + notes_commit=$1 && + fanout=$2 && + git ls-tree -r --name-only $notes_commit 2>/dev/null | + while read path + do + path_has_fanout $path $fanout || return 1 + done +} + test_expect_success 'creating many notes with git-notes' ' num_notes=300 && i=0 && @@ -20,7 +46,7 @@ test_expect_success 'creating many notes with git-notes' ' test_expect_success 'many notes created correctly with git-notes' ' git log | grep "^ " > output && - i=300 && + i=$num_notes && while test $i -gt 0 do echo " commit #$i" && @@ -30,34 +56,46 @@ test_expect_success 'many notes created correctly with git-notes' ' test_cmp expect output ' -test_expect_success 'many notes created with git-notes triggers fanout' ' - # Expect entire notes tree to have a fanout == 1 - git ls-tree -r --name-only refs/notes/commits | - while read path +test_expect_success 'stable fanout 0 is followed by stable fanout 1' ' + i=$num_notes && + fanout=0 && + while test $i -gt 0 do - echo $path | grep "^../[0-9a-f]*$" || { - echo "Invalid path \"$path\"" && - return 1; - } - done + i=$(($i - 1)) && + if touched_one_note_with_fanout refs/notes/commits~$i A $fanout + then + continue + elif test $fanout -eq 0 + then + fanout=1 && + if all_notes_have_fanout refs/notes/commits~$i $fanout + then + echo "Fanout 0 -> 1 at refs/notes/commits~$i" && + continue + fi + fi && + echo "Failed fanout=$fanout check at refs/notes/commits~$i" && + git ls-tree -r --name-only refs/notes/commits~$i && + return 1 + done && + all_notes_have_fanout refs/notes/commits 1 ' test_expect_success 'deleting most notes with git-notes' ' - num_notes=250 && + remove_notes=285 && i=0 && git rev-list HEAD | - while test $i -lt $num_notes && read sha1 + while test $i -lt $remove_notes && read sha1 do i=$(($i + 1)) && test_tick && - git notes remove "$sha1" || - exit 1 + git notes remove "$sha1" 2>/dev/null || return 1 done ' test_expect_success 'most notes deleted correctly with git-notes' ' - git log HEAD~250 | grep "^ " > output && - i=50 && + git log HEAD~$remove_notes | grep "^ " > output && + i=$(($num_notes - $remove_notes)) && while test $i -gt 0 do echo " commit #$i" && @@ -67,16 +105,29 @@ test_expect_success 'most notes deleted correctly with git-notes' ' test_cmp expect output ' -test_expect_success 'deleting most notes triggers fanout consolidation' ' - # Expect entire notes tree to have a fanout == 0 - git ls-tree -r --name-only refs/notes/commits | - while read path +test_expect_success 'stable fanout 1 is followed by stable fanout 0' ' + i=$remove_notes && + fanout=1 && + while test $i -gt 0 do - echo $path | grep -v "^../.*" || { - echo "Invalid path \"$path\"" && - return 1; - } - done + i=$(($i - 1)) && + if touched_one_note_with_fanout refs/notes/commits~$i D $fanout + then + continue + elif test $fanout -eq 1 + then + fanout=0 && + if all_notes_have_fanout refs/notes/commits~$i $fanout + then + echo "Fanout 1 -> 0 at refs/notes/commits~$i" && + continue + fi + fi && + echo "Failed fanout=$fanout check at refs/notes/commits~$i" && + git ls-tree -r --name-only refs/notes/commits~$i && + return 1 + done && + all_notes_have_fanout refs/notes/commits 0 ' test_done
-- 2.23.1