Re: [PATCH] [GSOC][RFC] format-patch: pass --right-only to range-diff

Taylor Blau [off-list ref] 于2021年3月9日周二 上午4:18写道：

On Sun, Mar 07, 2021 at 06:57:19AM +0000, ZheNing Hu via GitGitGadget wrote:

quoted

From: ZheNing Hu <redacted>

In https://lore.kernel.org/git/YBx5rmVsg1LJhSKN@nand.local/ (local),
Taylor Blau proposing 'git format-patch --cover-letter
--range-diff' may mistakenly place upstream commit in the
range-diff output. Teach `format-patch` pass `--right-only`
to range-diff, maybe can avoid this kind of mistake.

Because `git rebase --apply` will internally call `git
format-patch -k --stdout --full-index --cherry-pick --right-only
--src-prefix=a/ --dst-prefix=b/ --no-renames --no-cover-letter
--pretty=mboxrd --topo-order --no-base`, In order to avoid the
ambiguity of `--right-only`, users can call `format-patch
--range-diff --only-right` instead of `--right-only` to only emit
output related to the second range.

A couple of times this new option is called "--right-only" and other
times it is "--only-right". This comment makes me think that you meant
to call it "--only-right", but...

quoted

Signed-off-by: ZheNing Hu <redacted>
---
    [GSOC][RFC] format-patch: pass --right-only to range-diff

    Transfer parameters are relatively simple. But because I can' t
    reproduce the situation, There's no big difference between adding
    ---only-right and not adding ---only-right. So I haven't written the
    test files for the time being.

Note that I think (and Johannes--cc'd--could confirm) that what you want
is '--left-only' to discard rebased changes from the upstream branch:

In either case, this should help you reproduce it (and would be a good
starting point for adding a test case). Here, we're using '--left-only'
to discard changes from upstream (here, the 'main' branch) after
rebasing:

    #!/bin/sh

    set -e

    rm -fr repo
    git init repo
    cd repo

    git branch -M main

    echo "base" >base
    git add base
    git commit -m "base"

    git checkout -b my-feature
    echo "feature" >feature
    git add feature
    git commit -m "feature"

    base="$(git rev-parse main)"
    old="$(git rev-parse my-feature)"

    git checkout main
    echo "other" >>base
    git add base
    git commit -m "new"

    git checkout my-feature
    git rebase $base --onto main

    tip="$(git rev-parse my-feature)"

    git range-diff $base $old $tip
    git range-diff --left-only $base $old $tip

Thanks, I have seen an obvious phenomenon from
your shell script, and I wrote test code based on it.

quoted

    I may need to ask reviewers opinion first.

    this want to fix #876 Thanks.

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-898%2Fadlternative%2Fformat-patch-range-diff-right-only-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-898/adlternative/format-patch-range-diff-right-only-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/898

 Documentation/git-format-patch.txt |  5 ++++-
 builtin/log.c                      | 15 ++++++++++-----
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/Documentation/git-format-patch.txt b/Documentation/git-format-patch.txt
index 3e49bf221087..5dae34c3090b 100644
--- a/Documentation/git-format-patch.txt
+++ b/Documentation/git-format-patch.txt

@@ -27,7 +27,7 @@ SYNOPSIS
                 [--[no-]encode-email-headers]
                 [--no-notes | --notes[=<ref>]]
                 [--interdiff=<previous>]
-                [--range-diff=<previous> [--creation-factor=<percent>]]
+                [--range-diff=<previous> [--creation-factor=<percent>] [--right-only]]
                 [--filename-max-length=<n>]
                 [--progress]
                 [<common diff options>]

@@ -301,6 +301,9 @@ material (this may change in the future).
      creation/deletion cost fudge factor. See linkgit:git-range-diff[1])
      for details.

+--only-right:
+     Used with `--range-diff`, only emit output related to the second range.
+

s/--only-right/--right-only?

Now it's all "--left-only".

quoted

 --notes[=<ref>]::
 --no-notes::
      Append the notes (see linkgit:git-notes[1]) for the commit

diff --git a/builtin/log.c b/builtin/log.c
index f67b67d80ed1..5d2f39fd19a7 100644
--- a/builtin/log.c
+++ b/builtin/log.c

@@ -1153,7 +1153,7 @@ static void make_cover_letter(struct rev_info *rev, int use_separate_file,
                            struct commit *origin,
                            int nr, struct commit **list,
                            const char *branch_name,
-                           int quiet)
+                           int quiet, int right_only)
 {
      const char *committer;
      struct shortlog log;

@@ -1228,7 +1228,8 @@ static void make_cover_letter(struct rev_info *rev, int use_separate_file,
                      .creation_factor = rev->creation_factor,
                      .dual_color = 1,
                      .diffopt = &opts,
-                     .other_arg = &other_arg
+                     .other_arg = &other_arg,
+                     .right_only = right_only
              };

              diff_setup(&opts);

@@ -1732,7 +1733,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
      struct strbuf rdiff2 = STRBUF_INIT;
      struct strbuf rdiff_title = STRBUF_INIT;
      int creation_factor = -1;
-
+     int right_only = 0;

Nit: the newline between creation_factor's declaration and
builtin_format_patch_options's is good to keep.

quoted

      const struct option builtin_format_patch_options[] = {
              OPT_CALLBACK_F('n', "numbered", &numbered, NULL,
                          N_("use [PATCH n/m] even with a single patch"),

@@ -1814,6 +1815,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                           parse_opt_object_name),
              OPT_STRING(0, "range-diff", &rdiff_prev, N_("refspec"),
                         N_("show changes against <refspec> in cover letter or single patch")),
+             OPT_BOOL(0, "only-right", &right_only,
+                      N_("only emit output related to the second range")),
              OPT_INTEGER(0, "creation-factor", &creation_factor,
                          N_("percentage by which creation is weighted")),
              OPT_END()

@@ -2087,7 +2090,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
              creation_factor = RANGE_DIFF_CREATION_FACTOR_DEFAULT;
      else if (!rdiff_prev)
              die(_("--creation-factor requires --range-diff"));
-
+     if (right_only && !rdiff_prev)
+             die(_("--right_only requires --range-diff"));

These may be good to combine into one big conditional that dies whenever
an option requiring --range-diff is set, but --range-diff is not:

Good tip.

  if (!rdiff_prev) {
    if (creation_factor)
      die(_("--creation-factor requires --range-diff"));
    if (right_only)
      die(_("--right-only requires --range-diff"));
  }

Thanks,
Taylor

Thanks,
ZheNing Hu