Re: [PATCH v2 2/6] commit-graph: always parse before commit_graph_data_at()

On Wed, Feb 3, 2021 at 10:55 AM Taylor Blau [off-list ref] wrote:

On Tue, Feb 02, 2021 at 10:07:32PM -0500, Derrick Stolee wrote:

quoted

'clear' is probably fine. I was thinking it might be good to have
an option to the 'write' subcommand to clear the existing data, but
it's probably better as separate steps.

Wouldn't 'git commit-graph write --split=replace --reachable' do the
same thing? I know that you changed some of the spots where we load an
existing commit graph, so my claim might be out-of-date, but I'm pretty
sure that this would get you out of a broken state.

Thinking aloud, I'm not totally sure that we should be exposing "git
commit-graph clear" to users. The only time that you'd want to run this
is if you were trying to remove a corrupted commit-graph, so I'd rather
see guidance on how to do that safely show up in
Documentation/git-commit-graph.txt.

Throwing one more idea into the mix, git-worktree recently got a
`repair` subcommand. Even though it presently repairs a small set of
problems, the subcommand name is intentionally generic so as to
provide room for growth. One could imagine `git commit-graph repair`
being added to provide a user-friendly mechanism for recovering from
commit-graph damage.