bug? round-trip through fast-import/fast-export loses files
From: Priedhorsky, Reid <hidden>
Date: 2023-03-20 18:13:46
Hello,
I believe I’ve found a bug in Git. It seems that (1) round-tripping through
fast-export/fast-import a repository (2) that contains a commit that changes
a file to a directory (3) deletes the contents of that directory from the
repository.
Thank you for filling out a Git bug report!
Please answer the following questions to help us understand your issue.
What did you do before the bug happened? (Steps to reproduce your issue)
Run this shell script:
~~~~
#!/bin/bash
set -ex
mkdir -p /tmp/weirdal
cd /tmp/weirdal
git --version
# init repo
rm -Rf wd
mkdir wd
cd wd
git init -b main
# first commit - foo is a file
touch foo
git add -A
git commit -m 'file'
# second commit - foo is a directory
rm foo
mkdir foo
touch foo/bar
git add -A
git commit -m 'directory'
# the contents of foo are in the working dir and the repo
git status
ls -lR
git ls-tree --name-only -r HEAD
# import/export repository (add --full-tree to work around bug)
git fast-export --no-data -- --all > ../export
cat ../export
git fast-import --force --quiet < ../export
# bug: foo is still in the WD but not the repo; should still be both
git status
ls -lR
git ls-tree --name-only -r HEAD
#git fast-export --no-data -- --all | diff -u --text ../export - || true
~~~~
What did you expect to happen? (Expected behavior)
Repo should be unchanged, i.e.:
+ git status
On branch main
nothing to commit, working tree clean
What happened instead? (Actual behavior)
Git thinks foo/bar has been staged:
+ git status
On branch main
Changes to be committed:
(use "git restore --staged <file>..." to unstage)
new file: foo/bar
What's different between what you expected and what actually happened?
File foo/bar is staged when it should be unchanged.
Anything else you want to add:
This also happens in 2.38.1 built from source.
The bad behavior can be worked around with “--full-tree” on fast-export, but
the real repo where I want to do this is pretty large, so I’d prefer not to.
Note the “git fast-export” output:
commit refs/heads/main
mark :2
author Reid Priedhorsky [off-list ref] 1679330805 -0600
committer Reid Priedhorsky [off-list ref] 1679330805 -0600
data 10
directory
from :1
M 100644 e69de29bb2d1d6434b8b29ae775ad8c2e48c5391 foo/bar
D foo
It looks to me like the “M ... foo/bar” is being processed before “D foo”
when it should happen in the opposite order.
Please review the rest of the bug report below.
You can delete any lines you don't wish to share.
[System Info]
git version:
git version 2.40.0.71.g950264636c
cpu: x86_64
built from commit: 950264636c68591989456e3ba0a5442f93152c1a
sizeof-long: 8
sizeof-size_t: 8
shell-path: /bin/sh
uname: Linux 5.10.0-21-amd64 #1 SMP Debian 5.10.162-1 (2023-01-21) x86_64
compiler info: gnuc: 10.2
libc info: glibc: 2.31
$SHELL (typically, interactive shell): /bin/bash
[Enabled Hooks]
Thanks,
Reid
—
he/his