On Thu, Apr 25 2019, Eugeniu Rosca wrote: > On Thu, Apr 25, 2019 at 01:24:56AM +0200, Ævar Arnfjörð Bjarmason wrote: >> >> On Thu, Apr 25 2019, Eugeniu Rosca wrote: >> >> > Hi Ævar, >> > >> > Thanks for the amazingly fast reply and for the useful feature (yay!). >> > >> > On Wed, Apr 24, 2019 at 05:37:10PM +0200, Ævar Arnfjörð Bjarmason wrote: >> >> >> >> On Wed, Apr 24 2019, Ævar Arnfjörð Bjarmason wrote: >> >> >> >> > Add the ability for the -G<regex> pickaxe to search only through added >> >> > or removed lines in the diff, or even through an arbitrary amount of >> >> > context lines when combined with -U<n>. >> >> > >> >> > This has been requested[1][2] a few times in the past, and isn't >> >> > currently possible. Instead users need to do -G<regex> and then write >> >> > their own post-parsing script to see if the <regex> matched added or >> >> > removed lines, or both. There was no way to match the adjacent context >> >> > lines other than running and grepping the equivalent of a "log -p -U<n>". >> >> > >> >> > 1. https://public-inbox.org/git/xmqqwoqrr8y2.fsf@xxxxxxxxxxxxxxxxxxxxxxxxx/ >> >> > 2. https://public-inbox.org/git/20190424102609.GA19697@xxxxxxxxxxxxxxxxxxxxxx/ >> >> >> >> I see now once I actually read Eugeniu Rosca's E-Mail upthread instead >> >> of just knee-jerk sending out patches that this doesn't actually solve >> >> his particular problem fully. >> >> >> >> I.e. if you want some AND/OR matching support this --pickaxe-raw-diff >> >> won't give you that, but it *does* make it much easier to script up such >> >> an option. Run it twice with -G"\+<regex>" and -G"-<regex>", "sort | >> >> uniq -c" the commit list, and see which things occur once or twice. >> >> >> >> Of course that doesn't give you more complex nested and/or cases, but if >> >> git-log grew support for that like git-grep has the -G option could use >> >> that, although at that point we'd probably want to spend effort on >> >> making the underlying machinery smarter to avoid duplicate work. >> > >> > Purely from user's standpoint, I feel more comfortable with `git grep` >> > and `git log --grep` particularly b/c they support '--all-match' [2], >> > allowing more flexible multi-line searches. Based on your feedback, it >> > looks to me that `git log -G/-S` did not have a chance to develop their >> > features to the same level. >> > >> >> >> >> Furthermore, and quoting Eugeniu upthread: >> >> >> >> In the context of [1], I would like to find all Linux commits which >> >> replaced: >> >> 'devm_request_threaded_irq(* IRQF_SHARED *)' >> >> by: >> >> 'devm_request_threaded_irq(* IRQF_ONESHOT *)' >> >> >> >> Such AND/OR machinery would give you what you wanted *most* of the time, >> >> but it would also find removed/added pairs that were "unrelated" as well >> >> as "related". Solving *that* problem is more complex, but something the >> >> diff machinery could in principle expose. >> > >> > I expect some false positives, since git is agnostic on the language >> > used to write the versioned files (the latter sounds like a research >> > topic to me - I hope there is somebody willing to experiment with that >> > in future). >> >> I was thinking of something where the added/removed could be filtered to >> cases that occur in the same diff hunk. >> >> >> >> >> But the "-G<regex> --pickaxe-raw-diff" feature I have as-is is very >> >> useful, >> > >> > I agree. I am a bit bothered by the fact that >> > `git log --oneline -Ux -G<regex> --pickaxe-raw-diff` outputs the >> > contents/patch of a commit. My expectation is that we have the >> > `log -p` knob for that? >> >> This is unrelated to --pickaxe-raw-diff, -U<n> just implies -p in >> general. See e.g. "git log -U1". > > Oops. Since I use `-U<n>` mostly with `git show`, I missed the > implication. You are right. Then, my question is how users are > going to (quote from commit description): > >> >> > [..] search [..] through an arbitrary amount of >> >> > context lines when combined with -U<n>. > > and achieve a `git log --oneline` report, given that -U<n> unfolds > the commits? > > FTR, based on my quick experiments, --pickaxe-raw-diff does process > several lines of context by default (it appears to default to -U3). Yeah I should document this explicitly. We use the default diff context so if you just -G'foo.*bar' you'll find things in the 6x lines of context (3 before / 3 after), not just the "-" and "+" lines. It's a "feature", but we should be really clear about it, i.e. you need to anchor with "^[+-]" if you want the same thing that -G does for you now. I *do* find the default semantics really useful. Sometimes you can use -L, but I've often done manual greps with -U<n> for "let's find code changes anywhere in the project near places where we use some API", maybe we should pick -U0 with --pickaxe-raw-diff by default to avoid *that* particular surprise by default, but I think that would be even more confusing... >> >> >> I've had at least two people off-list ask me about a problem >> >> that would be solved by it just in the last 1/2 year (unrelated to them >> >> having seen the WIP patch I sent last October). >> >> >> >> It's more general than Junio's suggested --pickaxe-ignore-{add,del} >> > >> > As a user, I would be happier to freely grep in the raw commit contents >> > rather than learning a dozen of new options which provide small subsets >> > of the same functionality. So, I personally vote for the approach taken >> > by --pickaxe-raw-diff. This would also reduce the complexity of my >> > current git aliases and/or allow dropping some of them altogether. >> > >> > Quite off topic, but I also needed to come up with a solution to get >> > the C functions modified/touched by a git commit [3]. It is my >> > understanding that --pickaxe-raw-diff can't help here and I still have >> > to rely on parsing the output of `git log -p`? >> >> Yeah, it doesn't help with that. When it runs we haven't generated the >> context line or the "@@" line yet, that's later. You can breakpoint on >> xdl_format_hunk_hdr and diffgrep_consume to see it in action. >> >> It's a waste of CPU to generate that for all possible hunks, most of >> which we won't show at all. >> >> But it's of course possible to do so by running the full diff machinery >> over every commit and matching on the result, the current pickaxe is >> just taking shortcuts and not doing that. >> >> >> options[1], but those could be implemented in terms of this underlying >> >> code if anyone cared to have those as aliases. You'd just take the >> >> -G<regex> and prefix the <regex> with "^\+" or "^-" as appropriate and >> >> turn on the DIFF_PICKAXE_G_RAW_DIFF flag. >> >> >> >> 1. https://public-inbox.org/git/xmqqwoqrr8y2.fsf@xxxxxxxxxxxxxxxxxxxxxxxxx/ >> > >> > Thanks! >> > >> > [2] https://gitster.livejournal.com/30195.html >> > [3] https://stackoverflow.com/questions/50707171/how-to-get-all-c-functions-modified-by-a-git-commit
