[PATCH v2 0/5] builtin/history: some smaller UI improvements

Hi,

this patch series contains a small set of UI improvements for git-history(1):

  - The first two commits adapt git-history(1) so that it performs
    verifications before asking the user for input.

  - The last two commits rework the "--ref-action=" option to instead be
    split up into "--dry-run" and "--update-refs=" so that the option is
    less focussed on technical implementation details.

I decided to send this patch series as a small incremental step before sending `git history split`, also because that series conflicts with aa/add-p-no-auto-advance.

Changes in v2:
  - Use `strvec_pushv()` instead of looping around `strvec_push()`.
  - Document that "--dry-run" writes objects for later use.
  - Document the default value of "--update-refs=".
  - Mention the subtlety around false(1) in the commit messages.
  - Link to v1: https://lore.kernel.org/r/20260212-b4-pks-history-dry-run-v1-0-1ce03d631c1b@pks.im

Thanks!

Patrick

---
Patrick Steinhardt (5):
      builtin/history: perform revwalk checks before asking for user input
      builtin/history: check for merges before asking for user input
      builtin/history: replace "--ref-action=print" with "--dry-run"
      builtin/history: rename "--ref-action=" to "--update-refs="
      Documentation/git-history: document default for "--update-refs="

 Documentation/git-history.adoc |  14 ++-
 builtin/history.c              | 254 ++++++++++++++++++++++++++---------------
 t/t3451-history-reword.sh      |  20 +++-
 3 files changed, 182 insertions(+), 106 deletions(-)

Range-diff versus v1:

1:  a4b0654c49 ! 1:  495a8e7a1a builtin/history: perform revwalk checks before asking for user input
    @@ Commit message
         Extract the function to set up the revision walk and call it before we
         ask for user input to fix this.
     
    +    Adapt one of the tests that is expected to fail because of this check
    +    to use false(1) as editor. If the editor had been executed by Git, it
    +    would fail with the error message "Aborting commit as launching the
    +    editor failed."
    +
         Signed-off-by: Patrick Steinhardt <ps@pks.im>
     
      ## builtin/history.c ##
2:  3ea8f7740a ! 2:  13c5edbe7b builtin/history: check for merges before asking for user input
    @@ Commit message
         Fix this by checking whether the revwalk contains merge commits before
         we ask for user input.
     
    +    Adapt one of the tests that is expected to fail because of this check
    +    to use false(1) as editor. If the editor had been executed by Git, it
    +    would fail with the error message "Aborting commit as launching the
    +    editor failed."
    +
         Signed-off-by: Patrick Steinhardt <ps@pks.im>
     
      ## builtin/history.c ##
    @@ builtin/history.c: static int parse_ref_action(const struct option *opt, const c
     +	struct rev_info revs;
     +	int ret;
     +
    -+	for (size_t i = 0; i < revwalk_args->nr; i++)
    -+		strvec_push(&args, revwalk_args->v[i]);
    ++	strvec_pushv(&args, revwalk_args->v);
     +	strvec_push(&args, "--min-parents=2");
     +
     +	repo_init_revisions(repo, &revs, NULL);
3:  4e605e65e0 ! 3:  7226c4d1af builtin/history: replace "--ref-action=print" with "--dry-run"
    @@ Commit message
         Add a test to verify that both "--ref-action=" values behave as
         expected.
     
    +    This patch is best viewed with "--ignore-space-change".
    +
         Signed-off-by: Patrick Steinhardt <ps@pks.im>
     
      ## Documentation/git-history.adoc ##
    @@ Documentation/git-history.adoc: The following commands are available to rewrite
     -`--ref-action=(branches|head|print)`::
     +`--dry-run`::
     +	Do not update any references, but instead print any ref updates in a
    -+	format that can be consumed by linkgit:git-update-ref[1].
    ++	format that can be consumed by linkgit:git-update-ref[1]. Necessary new
    ++	objects will be written into the repository, so applying these printed
    ++	ref updates is generally safe.
     +
     +`--ref-action=(branches|head)`::
      	Control which references will be updated by the command, if any. With
4:  1da7284902 ! 4:  7f41026981 builtin/history: rename "--ref-action=" to "--update-refs="
    @@ Documentation/git-history.adoc: git-history - EXPERIMENTAL: Rewrite history
      DESCRIPTION
      -----------
     @@ Documentation/git-history.adoc: OPTIONS
    - 	Do not update any references, but instead print any ref updates in a
    - 	format that can be consumed by linkgit:git-update-ref[1].
    + 	objects will be written into the repository, so applying these printed
    + 	ref updates is generally safe.
      
     -`--ref-action=(branches|head)`::
     +`--update-refs=(branches|head)`::
-:  ---------- > 5:  0bc831fcab Documentation/git-history: document default for "--update-refs="

--- base-commit: 6fcee4785280a08e7f271bd015a4dc33753e2886 change-id: 20260212-b4-pks-history-dry-run-2b840e530ae6