Re: [PATCH] revision: allow pseudo options after --end-of-options

brian m. carlson [off-list ref] 于2021年7月9日周五 上午1:02写道：

On 2021-07-08 at 15:03:16, Jiang Xin wrote:

quoted

From: Jiang Xin <redacted>

Options and revisions can be seperated by the option "--end-of-options"
by introducing commit 19e8789b23 (revision: allow --end-of-options to
end option parsing, 2019-08-06).  The following command will show
revisions which have changes on file "bar" on a branch named "--foo":

    git rev-list --oneline --end-of-options --foo -- bar

If we want to see revisions between two revisions (rev1 and rev2), we
can use the following command:

    git rev-list --oneline --end-of-options rev1..rev2 --

We know that "rev1..rev2" is a shorthand for "rev2 --not rev1", but
we can not use the longer expression with option "--not" after the
"--end-of-options" option.  This is because the parser will not consume
revision pseudo options after seeing "--end-of-option".

Allow parsing revision pseudo options after "--end-of-options", the
following command is valid:

    git rev-list --oneline --end-of-options rev2 --not rev2 --

I don't think we want to do this.  The goal of --end-of-options is to
prevent parsing all future items as options, so if someone specifies a
revision starting with a dash, we don't end up with it being interpreted
as an option.

New test case in t6000 covered this case. Branch "--output=yikes"
which starts with a dash is used as revision after the option
"--end-of-options", and it won't be interpreted as an option.

    test_expect_success 'parse pseudo option "--not" after "--end-of-options"' '
        cat >expect <<-EOF &&
        > three
        EOF
        git log --pretty="%m %s" --end-of-options \
                HEAD --not --output=yikes -- \
                two/three >actual &&
        test_cmp expect actual
    '

But for the original implementation, because pseudo revision options
(--branches, --tags, --not, ..., etc) can not be used after the
"--end-of-options" option, we have to put "--end-of-options" at the
end of revisions, such as:

    git log --pretty="%m %s" rev1 --not rev2 rev3 rev4 \
            --end-of-options -- path/file

We can see from the above command, the option "--end-of-options" is
immediately followed by a dashdash. That is very strange.  DashDash is
designed to separate pathspecs from args, and "--end-of-options" is
designed to separate revisions from options. But because of the pseudo
revision options, "--end-of-options" is meaningless for commands
calling "setup_revisions()".

Yes, "--end-of-options" must be used if there is a revision which
starts with dash, such as branch "--output=yikes" in t6000. That's
even stranger, for we have to write  command in the middle of
revisions like this:

    git log --pretty="%m %s" rev1 --not rev2 rev3 \
            --end-of-options --output=yikes -- path/file

I know "rev1..rev2" and "rev2 ^rev1", but I prefer to use "rev1 --not
rev2 rev3" instead of "rev1 ^rev2 ^rev3".