Re: [PATCH v3 0/3] Use default values from settings instead of config

Glen Choo [off-list ref] writes:

Hi everyone! This patch was created in response to something we observed in
Google, where fsck failed to detect that the commit graph was invalid. We
initially assumed that fsck never checked the commit graph, but it turns out
that it does so only when core.commitgraph is set, even though we set defaults
for "whether to use the commit graph" in the repository settings.

With this merged to 'seen', the CI job with the extra set of
GIT_TEST_X settings fail.  When this topic is excluded, with
all the other topics in flight in 'seen', everything seems to
be OK.

For which GIT_TEST_X environment variables to set and export while
testing to trigger the problem, see [*1*]

For a successful test run of 'seen' without this topic, see [*2*]

For the test log of the failing run with this topic, see [*3*];
you'd need to be logged into GitHub to see the details of the errors
(e.g. click on "regular (linux-gcc...)" with red X sign on the left
hand side, then open "Run ci/print-test-failures.sh" and look for
"not ok").


[References]

*1* https://github.com/git/git/runs/3843549095?check_suite_focus=true#step:4:1677

    export GIT_TEST_SPLIT_INDEX=yes
    export GIT_TEST_MERGE_ALGORITHM=recursive
    export GIT_TEST_FULL_IN_PACK_ARRAY=true
    export GIT_TEST_OE_SIZE=10
    export GIT_TEST_OE_DELTA_SIZE=5
    export GIT_TEST_COMMIT_GRAPH=1
    export GIT_TEST_COMMIT_GRAPH_CHANGED_PATHS=1
    export GIT_TEST_MULTI_PACK_INDEX=1
    export GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP=1
    export GIT_TEST_ADD_I_USE_BUILTIN=1
    export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=master
    export GIT_TEST_WRITE_REV_INDEX=1
    export GIT_TEST_CHECKOUT_WORKERS=2

*2* https://github.com/git/git/actions/runs/1322907901 (feff65d)

    A successful CI run of 'seen' without gc/use-repo-settings.

*3* https://github.com/git/git/actions/runs/1322842689 (54a31af)

    CI run of 'seen' with gc/use-repo-settings that fails.

    The commits that is in the failing 'seen' but not in the
    succeeding tree are those from this topic, as can be seen here:

    $ git shortlog --no-merges 54a31af ^feff65d
    Glen Choo (3):
          fsck: verify commit graph when implicitly enabled
          fsck: verify multi-pack-index when implictly enabled
          gc: perform incremental repack when implictly enabled