Re: [PATCH v9 15/20] ref-filter: modify the 'lstrip=<N>' option to work with negative '<N>'
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Dec 27, 2016, 21:11 UTC
- Message-ID
- <xmqqo9zx6phw.fsf@gitster.mtv.corp.google.com>
- In-Reply-To
- <20161227162357.28212-16-Karthik.188@gmail.com>
Karthik Nayak <karthik.188@gmail.com> writes:
> Currently the 'lstrip=<N>' option only takes a positive value '<N>' > and strips '<N>' slash-separated path components from the left. Modify > the 'lstrip' option to also take a negative number '<N>' which would > only _leave_ behind 'N' slash-separated path components from the left.
"would only leave behind N components from the left" sounds as if the result is A/B, when you are given A/B/C/D/E and asked to lstrip:-2. Given these two tests added by the patch ...
> +test_atom head refname:lstrip=-1 master > +test_atom head refname:lstrip=-2 heads/master
... I somehow think that is not what you wanted to say. Instead, you strip from the left as many as necessary and leave -N components that appear at the right-most end, no?
Show 9 quoted lines
> --- a/Documentation/git-for-each-ref.txt > +++ b/Documentation/git-for-each-ref.txt > @@ -98,7 +98,8 @@ refname:: > abbreviation mode. If `lstrip=<N>` is appended, strips `<N>` > slash-separated path components from the front of the refname > (e.g., `%(refname:lstrip=2)` turns `refs/tags/foo` into `foo`. > - `<N>` must be a positive integer. > + if `<N>` is a negative number, then only `<N>` path components > + are left behind.
I think positive <N> is so obvious not to require an example but it is good that you have one. The negative <N> case needs illustration more than the positive case. Perhaps something like:
(e.g. %(refname:lstrip=-1) strips components of refs/tags/frotz
from the left to leave only one component, i.e. 'frotz').Would %(refname:lstrip=-4) attempt to strip components of refs/tags/frotz from the left to leave only four components, and because the original does not have that many components, it ends with refs/tags/frotz?
I am debating myself if we need something like "When the ref does not have enough components, the result becomes an empty string if stripping with positive <N>, or it becomes the full refname if stripping with negative <N>. Neither is an error." is necessary here. Or is it too obvious?