Re: [PATCH] checkout: Better error message on invalid branch name

Ævar Arnfjörð Bjarmason [off-list ref] writes:

Change the error message for `git checkout -b "I LOVE YOU"' and other
invalid branch names to say what branch names are invalid, rather than
just saying we don't like it.

Before:

    $ git checkout -b "I LOVE YOU"
    fatal: git checkout: we do not like 'I LOVE YOU' as a branch name.

After:

    $ git checkout -b "I LOVE YOU"
    fatal: git checkout: The name "I LOVE YOU" is not a valid Git branch name.
    A branch name can not:
        - Have a path component that begins with "."
        - Have a double dot ".."
        - Have an ASCII control character, "~", "^", ":" or SP, anywhere
        - End with a "/"
        - End with ".lock"
        - Contain a "\" (backslash

Cluttering the output without protecting it with "advice" does not look
like a "fix" nor improvement.

On Mon, Jun 21, 2010 at 20:58, Junio C Hamano [off-list ref] wrote:

Cluttering the output without protecting it with "advice" does not look
like a "fix" nor improvement.

The short version of the message would also need to be fixed then, to
do that properly would require bigger changes in the return code of
bad_ref_char and the functions that call it. Then we could have e.g.:

    $ git checkout -b "I LOVE YOU"
    fatal: git checkout: Branch name cannot contain ' ';  marked by
<-- HERE in 'I ' <-- HERE

Similar to what you get from:

    $ perl -e '/I LOVE [/'

That would also make the long version unnecessary, and maybe improve
some other error messages that deal with ref names.