Re: [PATCH 0/9] worktree: fix bugs and broaden --force applicability

[Jeff King <peff@peff.net>]

On Tue, Aug 28, 2018 at 05:20:17PM -0400, Eric Sunshine wrote:

> This series started as a fix for a bug reported by Peff[1] in which the
> "database" of worktrees could be corrupted (or at least become
> internally inconsistent) by having multiple worktree entries associated
> with the same path.
> 
> Peff's particular use-case for git-worktree is Documentation/doc-diff
> which wants to re-use a worktree if it exists or create it anew if it
> doesn't. Unfortunately, this is a bit more difficult than it should be
> if the worktree directory is deleted manually (without pruning the
> worktree entry) between script invocations. To simplify this use-case
> for tools, it was suggested[2] that "git worktree add --force" could
> deal with the problem of a registered-but-missing worktree (much as a
> tool might rely upon "mkdir -p" to create or re-use an existing
> directory). This series implements that proposal, as well.
> 
> Fixing the original bug revealed another existing bug, and after several
> additional "while we're here" changes, the series ended up a bit longer
> than expected.

Thanks for working on this. I think this nicely solves the problem I was
having.  I had a few minor comments which I sent in reply to individual
patches, but overall it looks very good. I'd be happy to see it picked
up with or without any changes based on my comments.

I'd want to do this on top. :)

-- >8 --
Subject: [PATCH] doc-diff: force worktree add

We avoid re-creating our temporary worktree if it's already
there. But we may run into a situation where the worktree
has been deleted, but an entry still exists in
$GIT_DIR/worktrees.

Older versions of git-worktree would annoyingly create a
series of duplicate entries. Recent versions now detect and
prevent this, allowing you to override with "-f". Since we
know that the worktree in question was just our temporary
workspace, it's safe for us to always pass "-f".

Signed-off-by: Jeff King <peff@peff.net>
---
 Documentation/doc-diff | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/doc-diff b/Documentation/doc-diff
index f483fe427c..19d841ddeb 100755
--- a/Documentation/doc-diff
+++ b/Documentation/doc-diff
@@ -54,7 +54,7 @@ fi
 # results that don't differ between the two trees.
 if ! test -d "$tmp/worktree"
 then
-	git worktree add --detach "$tmp/worktree" "$from" &&
+	git worktree add -f --detach "$tmp/worktree" "$from" &&
 	dots=$(echo "$tmp/worktree" | sed 's#[^/]*#..#g') &&
 	ln -s "$dots/config.mak" "$tmp/worktree/config.mak"
 fi
-- 
2.19.0.rc1.539.g3876d0831e