* GIT_CONFIG doesn't work as you mentioned and as was already mentioned in https://stackoverflow.com/questions/23400449/how-to-make-git-temporarily-ignore-gitconfig * `HOME= `doesn't work for many reasons: it breaks other commands as you mentioned, it breaks `~`, and it doesn't work if users' git config is in /Users/timothee/.config//git/config ; and pointing it to an alternate home where you'd have `newhome/.gitconfig` would require a lot of workarounds to update paths including `~` * `XDG_CONFIG_HOME= ` also doesn't work (even if users' git config is in /Users/timothee/.config//git/config), which really seems buggy, eg:`XDG_CONFIG_HOME= git diff HEAD^` is still reading `/Users/timothee/.config//git/config` somehow * GIT_CONFIG_NOGLOBAL is also not good, I want to be able to simply point my config to some place else, not simply suppress reading git config * require passing commands (eg `git -c`) is not good either; it'd require updating scripts that rely on git (this could be arbitrarily complex, sometimes impossible if you just have a binary and no source code access) In contrast, what I'm suggesting is extremely simple to use, robust, and my understanding is it shouldn't be hard to implement. ``` GITCONFIGFILE= git diff HEAD^ # empty config GITCONFIGFILE=/pathto/gitconfig2 git diff HEAD^ # uses specified git config file GITCONFIGFILE=/pathto/gitconfig2 run_some_complex_script # uses specified git config file everywhere ``` by contrast, any approach based on passing command line flag (eg `git -c /pathto/gitconfig2 diff HEAD^`) will make the last case impossible to do since you'd need to update every git command inside (which could be in a compiled binary, etc) What i'm asking is the analog of `TIGRC_USER` for tig (https://jonas.github.io/tig/doc/tig.1.html) and many other programs On Thu, Mar 19, 2020 at 9:51 AM Jeff King <peff@xxxxxxxx> wrote: > > On Thu, Mar 19, 2020 at 06:44:07AM +0000, Eric Wong wrote: > > > Timothee Cour <thelastmammoth@xxxxxxxxx> wrote: > > > git makes it impossible to ignore global gitconfig. This is > > > essentially what's being asked here: > > > https://stackoverflow.com/questions/23400449/how-to-make-git-temporarily-ignore-gitconfig > > > > > > ## proposal: > > > add an environment variable (like for tig and other programs), eg: > > > `GITCONFIGFILE=~/.gitconfig_temp git diff` > > > seems like an easy change that would make it easy for users to ignore > > > or override their gitconfig > > > > You can use GIT_CONFIG for that, and there's also > > GIT_CONFIG_NOSYSTEM. They're both documented in the > > git-config(5) manpage. > > I don't think $GIT_CONFIG is what Timothee whats. It only affects the > git-config command, not config lookup in other programs. And it > overrides _all_ config lookup, as if "git config --file" had been used. > > There's no variable to suppress just the user-level gitconfig. The usual > technique (that we use in the test scripts) is to point $HOME somewhere > else, but that may affect other programs. > > I wouldn't be opposed to GIT_CONFIG_NOGLOBAL if there's a use case, but > it sounds like the desire is to actually provide new config. That can > also be done for specific options with "git -c". Under the hood that is > using GIT_CONFIG_PARAMETERS in the environment; you can set it > individually, but note that it's a little picky about quoting (the > individual keys are shell-quoted, but it insists that there is an outer > layer of single-quotes, even if they weren't necessary; I wouldn't be > opposed to making it more friendly). You can see what it produces like > this: > > git -c alias.dump='!echo "$GIT_CONFIG_PARAMETERS"' dump > > -Peff
