“git pull” broken

问题:

I recently upgraded my MacBook Pro to Snow Leopard and "git pull" returns:

rakudo $ git pull
git: 'pull' is not a git-command. See 'git --help'

Did you mean this?
        shell
rakudo $ git-pull
-bash: git-pull: command not found

I've tried reinstalling via macports, but to no avail. Then I saw this

rakudo $ git --exec-path
/Users/ovid/libexec/git-core

That surprised me as that directory does not exist, nor has it ever existed. Google is not helping here. Hopefully you can :)

回答1:

Looking in the source of git, there's a comment in git.c:

/*
 * We use PATH to find git commands, but we prepend some higher
 * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 * environment, and the $(gitexecdir) from the Makefile at build
 * time.
 */

If you call git --exec-path, you end up calling const char *git_exec_path(void) in exec_cmd.c. That looks like this:

const char *env;

if (argv_exec_path)
    return argv_exec_path;

env = getenv(EXEC_PATH_ENVIRONMENT);
if (env && *env) {
    return env;
}

return system_path(GIT_EXEC_PATH);

Now, _argv_exec_path_ is set when you say --exec-path=/some/where so can be discounted. You've stated that the environment variable isn't set. GIT_EXEC_PATH is defined during compilation in the Makefile. Going backwards, it seems to be defined as just libexec/git-core. So, we need to look at what system_path() does instead.

I'm not sure whether RUNTIME_PREFIX is defined for you. But while nosing in the Makefile, I did notice that prefix defaults to $(HOME). I suspect that this may be the cause of your problems.

The simple answer is to put this in ~/.bashrc:

export GIT_EXEC_PATH=/opt/local/libexec/git-core

If you want to find out more about what's going on, you'll probably have to recompile git using port -d upgrade -f git-core (or similar) and look closely at the build log to see where prefix is being set. Incidentally, port cat git-core shows heavy usage of ${prefix} so it should (hopefully) be obvious.

回答2:

Interesting. try echo $GIT_EXEC_PATH, which git. It's unlikely to be related to the snow beast…

回答3:

On my system, libexec/git-core is in /usr/local and not /opt/local. The /usr/local/libexec directory had only root accessible permissions for me, and this fixed the problem:

sudo chmod a+rx /usr/local/libexec

回答4:

Have you tried the steps on the ports Migration wiki page? It was painful, but after doing the --force uninstall and reinstall process, I haven't had any issues with any of my ports, which includes git (with pretty much every variant turned on).

回答5:

Git compiles so easily there's really not any reason to bother with any of macports' craziness. Get rid of whatever's in /opt and try building it the normal way. Odds are good it will work.

回答6:

Another option is to download from the helpful page on GitHub:

http://help.github.com/mac-git-installation/

They have a stand-alone installer (though the second option there is MacPorts...)

They used to have a very nice all in one page tutorial that seems to be splintered now. What a shame.

回答7:

For me, this was an issue only specifically relevant to my brew install. On OSX 10.9.2, I had brew installed under root, so this works for me:

sudo su
export GIT_EXEC_PATH=/Applications/Xcode.app/Contents/Developer/usr/libexec/git-core
brew update # or whatever you want from here