On 25/03/11 07:57PM, Jeff King wrote: > On Mon, Mar 10, 2025 at 02:28:25PM -0500, Justin Tobler wrote: > > > To make machine parsing easier, this series introduces a NUL-delimited > > output mode for git-rev-list(1) via a `-z` option following a suggestion > > from Junio in a previous thread[1]. In this mode, instead of LF, each > > object is delimited with two NUL bytes and any object metadata is > > separated with a single NUL byte. Examples: > > > > <oid> NUL NUL > > <oid> [NUL <path>] NUL NUL > > ?<oid> [NUL <token>=<value>]... NUL NUL > > > > In this mode, path and value info are printed as-is without any special > > encoding or truncation. > > I think this is a good direction, but I have two compatibility > questions: > > 1. What should "git rev-list -z --stdin" do? In most other programs > with a "-z" option it affects both input and output. I don't > particularly care about this case myself, but it will be hard to > change later. So we probably want to decide now. As others suggested in this thread, in the next version I'll make revision and pathspec parsing on stdin also be NUL-delimited when -z is used. > 2. I was a little surprised that rev-list already takes a "-z" option, > but it doesn't seem to do anything. I guess it's probably picked up > via diff_opt_parse(), though (I think) you can't actually trigger a > diff via rev-list itself. So even though this is a change in > behavior, probably nobody would have been using it until now? This is correct. Technically git-rev-list(1) accepts all the common diff options because it invokes `setup_revisions()`. From my understanding it isn't possible to trigger diffs so I think parsing diff options is unnecessary to begin with. As it also isn't a documented option, I figured -z being an accepted option for git-rev-list(1) is largely an unintended consequence of it using `setup_revisions()` and should be fine to use. > If it is possible to see some effect from "-z" now (I didn't dig > very far), then it may be better to continue to let the diff > options parser handle it, and simply pick the result out of > revs.diffopt.line_termination. As your patch 3 is written, I think > the diff code probably doesn't see it anymore at all. As currently implemented, the early parsing of -z doesn't effect the diff options parsing in `setup_revisions()`. The early parsing doesn't remove the option and thus it continues to be set in the diff options. Furthermore, revision and pathspec argument parsing is all handled in `setup_revisions()` so if we want to NUL-delimit arguments parsed on stdin with -z, we would still need to parse the option early anyway. I think it should be fine to leave the early -z option parsing as-is. Thanks, -Justin
