Why does 'git branch -d' act differntly after clone?

Why does 'git branch -d' act differntly after clone?

[Konstantin Hollerith]

Hi,

I created a simple repository.
If i create a new branch from master and commit some changes and
then delete it with

    git branch -d neuerTestBranch

I'll get a error:

    error: The branch 'neuerTestBranch' is not fully merged.

I like that error, it reminds me, that i forgot to merge.
However, if i don't delete this branch and clone the Repository somewhere
else, i don't get the error anymore. When i delete the branch now, i get
this message:

    warning: deleting branch 'neuerTestBranch' that has been merged to
    'refs/remotes/origin/neuerTestBranch', but not yet merged to HEAD.

And the Branch is deleted right away.

Why does git branch -d acts differently after a clone?
Is this behavior maybe a Bug?
Is it possible to force a behavior like the first in cloned repositories,
too?

I use 'git version 2.5.0.windows.1'.

Cheers,
Konstantin

Re: Why does 'git branch -d' act differntly after clone?

[Junio C Hamano]

Konstantin Hollerith <khollerith@gmail.com> writes:

> Why does git branch -d acts differently after a clone?

In the former case, that branch is the only thing that knows about
the commits near the tip of it.  Immediately after you clone that
repository, you have a copy of that branch as a remote-tracking
branch for origin/neuerTestBranch.  You didn't say how you got a
local copy of it in there, but I'd imagine that in the clone you did
something like:

    $ git checkout neuerTestBranch

which is a short-hand for

    $ git checkout -b neuerTestBranch origin/neuerTestBranch

and then went back to a branch other than that branch when you asked
the branch to be removed, e.g.

    $ git checkout master
    $ git branch -d neuerTestBranch

without building any further history on neuerTestBranch.

Now, your local neuerTestBranch is a mere unmodified copy of the
remote-tracking branch origin/neuerTestBranch; the commits on the
former will not become unreachable if you remove neuerTestBranch,
because they are all reachable via origin/neuerTestBranch.  And that
is why the deletion of it has less severe potential of information
lossage, compared to the original case where you attempt to remove
the only copy.