Re: "git diff --no-index" Implies "--exit-code"

> I suspect this may be a bug:
> Because I am not specifying the "--exit-code" flag,  I expect "git diff --no-index" to have the same exit code style as git diff.
> But it does not.  
> See comment in source linked below.  
> Or, if this is intended, this side effect should be noted in the documentation for --no-index.
> 
> https://git-scm.com/docs/git-diff
> --exit-code
> Make the program exit with codes similar to diff(1). That is, it exits with 1 if there were differences and 0 means no differences.
> 
> git diff [<options>] --no-index [--] <path> <path>
> This form is to compare the given two paths on the filesystem. You can omit the --no-index option when running the command in a working tree controlled by Git and at least one of the paths points outside the working tree, or when running the command outside a working tree controlled by Git.
> 
> 
> https://github.com/git/git/blob/83232e38648b51abbcbdb56c94632b6906cc85a6/diff-no-index.c#L307
> /*
>  * The return code for --no-index imitates diff(1):
>  * 0 = no changes, 1 = changes, else error
> */