Re: 6d4bb3833c3d2114d (fetch: verify we have everything we need before updating our ref) breaks fetch

On Wed, 2011-09-28 at 14:53 -0400, Jeff King wrote:

On Wed, Sep 28, 2011 at 06:04:27PM +0200, Carlos Martín Nieto wrote:

quoted

Whilst trying to do some work related to fetch, I came across a
regression in the 'next' branch. Bisecting gave me this commit as
breaking point (and I tried with the parent and there it worked). When
doing 'git fetch', rev-list will complain about usage, and fetch will
say that we didn't receive enough, even though earlier versions of git
have no problems. This fails both on github and on git.or.cz and for git
and http transports:

$ ./git-fetch git://repo.or.cz/git
usage: git rev-list [OPTION] <commit-id>... [ -- paths... ]

Hmm. I notice you're running a not-installed version of fetch. Might
this be a problem with a new git fetch running an older, installed
version of rev-list?

Yes, this seems indeed to be the case.

The commit you mention calls rev-list with --verify-objects, but that
feature is only added in the parent commit. So I can reproduce your
issue with:

  $ git checkout 6d4bb38~2 ;# or anything before --verify-objects
  $ make install
  $ git checkout 6d4bb38
  $ make
  $ ./git-fetch git://repo.or.cz/git

but this works (because it sets the exec path properly):

  $ ./bin-wrappers/git fetch git://repo.or.cz/git

as does this:

  $ make install
  $ ./git-fetch git://repo.or.cz/git

So I don't think there's a bug. It's just that running compiled programs
straight out of the build directory isn't supported. It works _most_ of
the time, but as you can see, you may end up calling older, installed
versions of git. The bin-wrappers scripts set up the exec path properly
to let you test.

Indeed, as both you and Junio pointed out (within three minutes of each
other :) I was running git from the build directory and expected it to
work, as I was testing a few changed I had made to the fetch code.

Mea culpa, I tend to forget that git tends to behave like a bunch of
shell scripts that happen to be written in C. Thanks to both.

   cmn