git config error message

Hello,

git config --get issues an error message when the specified value contains a section that does not exist, but does not issue any message when the value contains a key that does not exist while in both cases returning a status 1. E.g.

$ git config --get xxx error: key does not contain a section: xxx

$ git config --get xxx.yyy

Proposal: to issue an error message also when the key does not exist.

-Angelo Borsotti

Angelo Borsotti <angelo.borsotti@gmail.com> writes:

The two cases are different: a key without a section is malformed, whereas a nonexistent value is usually not an error (use the default instead).

Andreas.

Hi Andreas,

I wrote "value", but I meant "name". The first example I made contains a name with a nonexistent section, the second a name with a nonexistent key.

-Angelo

Angelo Borsotti <angelo.borsotti@gmail.com> writes:

And a nonexistent key is a valid key, so not an error.

Andreas.

On Sat, Oct 27, 2012 at 9:32 AM, Angelo Borsotti <angelo.borsotti@gmail.com> wrote:

Hi Angelo,

This still wouldn't be an error condition though, especially in terms of how "git config" should treat it. It should be up to the consumer of the information to display, or not, any error or diagnostics that don't result from either a bad request (your first case) or a malformed configuration file. This fits with the callback nature of how the config file is parsed by builtin tools. The exit code from "git config" with a missing key is enough for the consumer to make this decision.

This is just my take on it, but I think the current approach makes sense.

Thanks -Ben

Hi Ben

The man page says:

   "This command will fail with non-zero status upon error."

Of course, one might claim that this does not mean the truth of the reverse condition, i.e. that when the command returns 1 that is necessarily an error, but I would leave that avenue of thinking to philosophers. Besides that, it is common practice in *nix OSs to consider a return != 0 as an error.

A well-behaved, user-friendly program, when detects an error tells the user what went wrong. How can otherwise the user tell a corrupted configuration file from a missing key?

Of course, is is possible to provide a git-config that simply returns 0 when it has got the key and 1 when it does not, without issuing any error message, but the current one is not like that, it is a middle way solution.

-Angelo

Angelo Borsotti <angelo.borsotti@gmail.com> writes:

Is grep not finding a match an error? Is cmp finding a difference an error? It all depends on the context.

You cannot, as long as your configuration file is well-formed, because a missing key is an expected condition in many cases.

Andreas.

Hi Andreas,

Manpage of grep, exit staus:

   "Normally, the exit status is 0 if selected lines are found and 1
otherwise. But the exit status is 2 if an error occurred, ..."

cmp uses the same convention (albeit not reported in its manpage).

I am not stating that all linux commands and utilities follow exactly the same convention, but these two are at least consistent with themselves always returning an exit status that has a well defined meaning. git-config returns consistently the exit status, it only issues in certain cases messages and in others not. A consistent solution could be for it to return 0 upon success, 1 when the section or key is absent, and 2 when the config file does not exist or is corrupt issuing also an error message.

-Angelo

Angelo Borsotti <angelo.borsotti@gmail.com> writes:

When the key is malformed you get an error, otherwise not.

Andreas.