Re: git merge -s subtree seems to be broken.

[George Shammas <georgyo@xxxxxxxxx>]

Bisecting around, this might be the commit that introduced the breakage.

https://github.com/git/git/commit/d8febde

I really hope that it hasn't been broken for 5 years and I am just doing something wrong.

On Tue, Jul 31, 2018 at 10:09 AM George Shammas <georgyo@xxxxxxxxx> wrote:

At work, we recently updated from a massively old version of git (1.7.10) to 2.18. There are a few code bases that use subtrees, and they seem to have completely broke when trying to merge in updates.

I have confirmed that it works correctly in 1.7.10.  The 2.18 behavior is clearly incorrect.

git init

echo init > test

git add test

git commit -m init

git remote add tig https://github.com/jonas/tig.git

git fetch tig

git merge -s ours --no-commit --allow-unrelated-histories tig-2.3.0

git read-tree --prefix=src/ -u tig-2.3.0

git commit -m "Get upstream tig-2.3.0"

# Notice how the history are merged, and that the source from the upstream repo is in src

echo update > test

git commit -a -m "test"

git merge -s subtree tig-2.4.0

# Boom, in 2.18 instead of merging into the subtree, it just deletes everything in the repository, which is clearly the wrong behavior.