Re: [PATCH 1/1] commit-graph: define GIT_TEST_COMMIT_GRAPH

>
> From: Derrick Stolee <dstolee@microsoft.com>
>
> The commit-graph feature is tested in isolation by
> t5318-commit-graph.sh and t6600-test-reach.sh, but there are many
> more interesting scenarios involving commit walks. Many of these
> scenarios are covered by the existing test suite, but we need to
> maintain coverage when the optional commit-graph structure is not
> present.
>
> To allow running the full test suite with the commit-graph present,
> add a new test environment variable, GIT_TEST_COMMIT_GRAPH. Similar
> to GIT_TEST_SPLIT_INDEX, this variable makes every Git command try
> to load the commit-graph when parsing commits, and writes the
> commit-graph file after every 'git commit' command.
>
> There are a few tests that rely on commits not existing in
> pack-files to trigger important events, so manually set
> GIT_TEST_COMMIT_GRAPH to false for the necessary commands.

> diff --git a/t/t0410-partial-clone.sh b/t/t0410-partial-clone.sh
> index 4984ca583d..73d5284a91 100755
> --- a/t/t0410-partial-clone.sh
> +++ b/t/t0410-partial-clone.sh
> @@ -181,7 +181,7 @@ test_expect_success 'rev-list stops traversal at missing and promised commit' '
>
>         git -C repo config core.repositoryformatversion 1 &&
>         git -C repo config extensions.partialclone "arbitrary string" &&
> -       git -C repo rev-list --exclude-promisor-objects --objects bar >out &&
> +       GIT_TEST_COMMIT_GRAPH=0 git -C repo rev-list --exclude-promisor-objects --objects bar >out &&