On Fri, Jul 26 2019, Junio C Hamano wrote:
> Ævar Arnfjörð Bjarmason <ava...@gmail.com> writes: > >> FWIW what I meant was not that we'd run around and iconv() things, it >> wouldn't make much sense to e.g. iconv() some PNG data to be "UTF-8 >> valid", which presumably would be the end result of something like that. >> >> Rather that this model of assuming that a UTF-8 pattern means we can >> consider everything in the repo UTF-8 in git-grep doesn't make sense. My >> kwset patches *revealed* that problem in a painful way, but it was there >> already. > > We already do assume that pathnames are UTF-8 (pathspecs on MacOS > are converted and then they are matched assuming that property). > Further, with the same mechanism, I think there is an assumption > that anything that comes from the command line is UTF-8 (and if I > recall correctly, doesn't the Windows port of Git force us to use > the same assumption---I recall we needed tests tweak for that). > > In the very very longer term, I do not think we would want to keep > the assumption that the text encoding of blobs is always UTF-8, and > it would be nice to extend the system, so that blob data could be > marked in some way to say "I'm in Big-5, and not in UTF-8, so please > treat me as such" and magically the needle and the haystack can be > made to agree, with iconv() either one of them. > > But I do not think the current topic to fix the immediate/imminent > breakage should not be distracted by that. Let's keep assuming that > any blob, when it is text, is UTF-8. > > And from that point of view, I think the two pieces of idea in your > earlier message does make sense. We can try to match as binary most > of the time, as UTF-8 would not let a valid UTF-8 needle match in > the haystack starting in the middle of a character. *nod* > When the user is trying to match case-insensitively, we know the > haystack in which the user is interested in finding the needle is > text, even though there may be non-text blobs as well. > > For example, "git grep -i 'foo' t/" may find a few png files under > the t/ directory. We do not care if they happen to contain Foo and > we do not mind if they appear or do not appear in the result. The > only two things we care about are (1) foo, Foo, FOO are found in the > text files under t/ and (2) the command does not die in the middle, > before processing all the files, only because a png file it found > were not UTF-8 valid. I think this part's a step too far, and not how e.g. GNU grep works. Peeking into binary data in a text grep is what people expect, e.g. because you might want to recursively grep mixed text/mp3s for an author. The text part of the mp3s means that metadata will be grepped for inside the binary files. Getting that right is hard around the edges though...
