Re: [PATCH v2 4/5] rebase -i: support --ignore-date

[Elijah Newren <newren@gmail.com>]

On Wed, Apr 29, 2020 at 3:26 AM Phillip Wood <phillip.wood123@gmail.com> wrote:
>
> From: Phillip Wood <phillip.wood@dunelm.org.uk>
>
> As part of the on-going effort to retire the apply rebase backend
> teach the merge backend how to handle --ignore-date. We take care to
> handle the combination of --ignore-date and
> --committer-date-is-author-date in the same way as the apply backend.
>
> Original-patch-by: Rohit Ashiwal <rohit.ashiwal265@gmail.com>
> Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
> ---
>  Documentation/git-rebase.txt   |  7 +++--
>  builtin/rebase.c               | 13 +++++---
>  sequencer.c                    | 49 +++++++++++++++++++++++++++--
>  sequencer.h                    |  1 +
>  t/t3436-rebase-more-options.sh | 57 ++++++++++++++++++++++++++++++++++
>  5 files changed, 117 insertions(+), 10 deletions(-)
>
> diff --git a/Documentation/git-rebase.txt b/Documentation/git-rebase.txt
> index 8c62645b8c..96c7125791 100644
> --- a/Documentation/git-rebase.txt
> +++ b/Documentation/git-rebase.txt
> @@ -443,8 +443,9 @@ See also INCOMPATIBLE OPTIONS below.
>         date. This option implies --force-rebase.
>
>  --ignore-date::
> -       This flag is passed to 'git am' to change the author date
> -       of each rebased commit (see linkgit:git-am[1]).
> +       Instead of using the author date of the original commit, use
> +       the current time as the author date of the rebased commit.  This
> +       option implies `--force-rebase`.
>  +
>  See also INCOMPATIBLE OPTIONS below.
>
> @@ -582,7 +583,6 @@ INCOMPATIBLE OPTIONS
>  The following options:
>
>   * --apply
> - * --ignore-date
>   * --whitespace
>   * -C
>
> @@ -610,6 +610,7 @@ In addition, the following pairs of options are incompatible:
>   * --preserve-merges and --empty=
>   * --preserve-merges and --ignore-whitespace
>   * --preserve-merges and --committer-date-is-author-date
> + * --preserve-merges and --ignore-date
>   * --keep-base and --onto
>   * --keep-base and --root
>
> diff --git a/builtin/rebase.c b/builtin/rebase.c
> index 357cd6acf3..cf86240bc8 100644
> --- a/builtin/rebase.c
> +++ b/builtin/rebase.c
> @@ -90,6 +90,7 @@ struct rebase_options {
>         char *gpg_sign_opt;
>         int autostash;
>         int committer_date_is_author_date;
> +       int ignore_date;
>         char *cmd;
>         int allow_empty_message;
>         int rebase_merges, rebase_cousins;
> @@ -129,6 +130,7 @@ static struct replay_opts get_replay_opts(const struct rebase_options *opts)
>         replay.reschedule_failed_exec = opts->reschedule_failed_exec;
>         replay.committer_date_is_author_date =
>                                         opts->committer_date_is_author_date;
> +       replay.ignore_date = opts->ignore_date;
>         replay.gpg_sign = xstrdup_or_null(opts->gpg_sign_opt);
>         replay.strategy = opts->strategy;
>
> @@ -1008,6 +1010,8 @@ static int run_am(struct rebase_options *opts)
>                 argv_array_push(&am.args, "--ignore-whitespace");
>         if (opts->committer_date_is_author_date)
>                 argv_array_push(&opts->git_am_opts, "--committer-date-is-author-date");
> +       if (opts->ignore_date)
> +               argv_array_push(&opts->git_am_opts, "--ignore-date");
>         if (opts->action && !strcmp("continue", opts->action)) {
>                 argv_array_push(&am.args, "--resolved");
>                 argv_array_pushf(&am.args, "--resolvemsg=%s", resolvemsg);
> @@ -1515,8 +1519,8 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
>                 OPT_BOOL(0, "committer-date-is-author-date",
>                          &options.committer_date_is_author_date,
>                          N_("make committer date match author date")),
> -               OPT_PASSTHRU_ARGV(0, "ignore-date", &options.git_am_opts, NULL,
> -                                 N_("passed to 'git am'"), PARSE_OPT_NOARG),
> +               OPT_BOOL(0, "ignore-date", &options.ignore_date,
> +                        "ignore author date and use current date"),
>                 OPT_PASSTHRU_ARGV('C', NULL, &options.git_am_opts, N_("n"),
>                                   N_("passed to 'git apply'"), 0),
>                 OPT_BOOL(0, "ignore-whitespace", &options.ignore_whitespace,
> @@ -1809,13 +1813,12 @@ int cmd_rebase(int argc, const char **argv, const char *prefix)
>             options.autosquash) {
>                 allow_preemptive_ff = 0;
>         }
> -       if (options.committer_date_is_author_date)
> +       if (options.committer_date_is_author_date || options.ignore_date)
>                 options.flags |= REBASE_FORCE;
>
>         for (i = 0; i < options.git_am_opts.argc; i++) {
>                 const char *option = options.git_am_opts.argv[i], *p;
> -               if (!strcmp(option, "--ignore-date") ||
> -                   !strcmp(option, "--whitespace=fix") ||
> +               if (!strcmp(option, "--whitespace=fix") ||
>                     !strcmp(option, "--whitespace=strip"))
>                         allow_preemptive_ff = 0;
>                 else if (skip_prefix(option, "-C", &p)) {
> diff --git a/sequencer.c b/sequencer.c
> index 8dff8b9b95..339dbf4a59 100644
> --- a/sequencer.c
> +++ b/sequencer.c
> @@ -150,6 +150,7 @@ static GIT_PATH_FUNC(rebase_path_refs_to_delete, "rebase-merge/refs-to-delete")
>   */
>  static GIT_PATH_FUNC(rebase_path_gpg_sign_opt, "rebase-merge/gpg_sign_opt")
>  static GIT_PATH_FUNC(rebase_path_cdate_is_adate, "rebase-merge/cdate_is_adate")
> +static GIT_PATH_FUNC(rebase_path_ignore_date, "rebase-merge/ignore_date")
>  static GIT_PATH_FUNC(rebase_path_orig_head, "rebase-merge/orig-head")
>  static GIT_PATH_FUNC(rebase_path_verbose, "rebase-merge/verbose")
>  static GIT_PATH_FUNC(rebase_path_quiet, "rebase-merge/quiet")
> @@ -889,6 +890,24 @@ static const char *author_date_from_env_array(const struct argv_array *env)
>         BUG("GIT_AUTHOR_DATE missing from author script");
>  }
>
> +/* Construct a free()able author string with current time as the author date */
> +static char *ignore_author_date(const char *author)
> +{
> +       int len = strlen(author);
> +       struct ident_split ident;
> +       struct strbuf new_author = STRBUF_INIT;
> +
> +       if (split_ident_line(&ident, author, len) < 0) {
> +               error(_("malformed ident line '%s'"), author);
> +               return NULL;
> +       }
> +       len = ident.mail_end - ident.name_begin + 1;
> +
> +       strbuf_addf(&new_author, "%.*s ", len, ident.name_begin);
> +       datestamp(&new_author);
> +       return strbuf_detach(&new_author, NULL);
> +}
> +
>  static const char staged_changes_advice[] =
>  N_("you have staged changes in your working tree\n"
>  "If these changes are meant to be squashed into the previous commit, run:\n"
> @@ -957,7 +976,11 @@ static int run_git_commit(struct repository *r,
>
>         if (opts->committer_date_is_author_date)
>                 argv_array_pushf(&cmd.env_array, "GIT_COMMITTER_DATE=%s",
> +                                opts->ignore_date ?
> +                                "" :
>                                  author_date_from_env_array(&cmd.env_array));
> +       if (opts->ignore_date)
> +               argv_array_push(&cmd.env_array, "GIT_AUTHOR_DATE=");
>
>         argv_array_push(&cmd.args, "commit");
>
> @@ -1386,7 +1409,8 @@ static int try_to_commit(struct repository *r,
>                 strbuf_addf(&date, "@%.*s %.*s",
>                             (int)(ident.date_end - ident.date_begin), ident.date_begin,
>                             (int)(ident.tz_end - ident.tz_begin), ident.tz_begin);
> -               res = setenv("GIT_COMMITTER_DATE", date.buf, 1);
> +               res = setenv("GIT_COMMITTER_DATE",
> +                            opts->ignore_date ? "" : date.buf, 1);
>                 strbuf_release(&date);
>
>                 if (res)
> @@ -1452,6 +1476,15 @@ static int try_to_commit(struct repository *r,
>
>         reset_ident_date();
>
> +       if (opts->ignore_date) {
> +               author = ignore_author_date(author);
> +               if (!author) {
> +                       res = -1;
> +                       goto out;
> +               }
> +               free(author_to_free);
> +               author_to_free = (char *)author;
> +       }
>         if (commit_tree_extended(msg->buf, msg->len, &tree, parents,
>                                  oid, author, opts->gpg_sign, extra)) {
>                 res = error(_("failed to write commit object"));
> @@ -2581,6 +2614,11 @@ static int read_populate_opts(struct replay_opts *opts)
>                         opts->committer_date_is_author_date = 1;
>                 }
>
> +               if (file_exists(rebase_path_ignore_date())) {
> +                       opts->allow_ff = 0;
> +                       opts->ignore_date = 1;
> +               }
> +
>                 if (file_exists(rebase_path_reschedule_failed_exec()))
>                         opts->reschedule_failed_exec = 1;
>
> @@ -2673,6 +2711,8 @@ int write_basic_state(struct replay_opts *opts, const char *head_name,
>                 write_file(rebase_path_keep_redundant_commits(), "%s", "");
>         if (opts->committer_date_is_author_date)
>                 write_file(rebase_path_cdate_is_adate(), "%s", "");
> +       if (opts->ignore_date)
> +               write_file(rebase_path_ignore_date(), "%s", "");
>         if (opts->reschedule_failed_exec)
>                 write_file(rebase_path_reschedule_failed_exec(), "%s", "");
>
> @@ -3595,7 +3635,11 @@ static int do_merge(struct repository *r,
>
>                 if (opts->committer_date_is_author_date)
>                         argv_array_pushf(&cmd.env_array, "GIT_COMMITTER_DATE=%s",
> +                                        opts->ignore_date ?
> +                                        "" :
>                                          author_date_from_env_array(&cmd.env_array));
> +               if (opts->ignore_date)
> +                       argv_array_push(&cmd.env_array, "GIT_AUTHOR_DATE=");
>
>                 cmd.git_cmd = 1;
>                 argv_array_push(&cmd.args, "merge");
> @@ -3875,7 +3919,8 @@ static int pick_commits(struct repository *r,
>         if (opts->allow_ff)
>                 assert(!(opts->signoff || opts->no_commit ||
>                                 opts->record_origin || opts->edit ||
> -                               opts->committer_date_is_author_date));
> +                               opts->committer_date_is_author_date ||
> +                               opts->ignore_date));
>         if (read_and_refresh_cache(r, opts))
>                 return -1;
>
> diff --git a/sequencer.h b/sequencer.h
> index 4ab94119ae..3587878e3b 100644
> --- a/sequencer.h
> +++ b/sequencer.h
> @@ -46,6 +46,7 @@ struct replay_opts {
>         int quiet;
>         int reschedule_failed_exec;
>         int committer_date_is_author_date;
> +       int ignore_date;
>
>         int mainline;
>
> diff --git a/t/t3436-rebase-more-options.sh b/t/t3436-rebase-more-options.sh
> index 84b9d5d37f..6cd3848689 100755
> --- a/t/t3436-rebase-more-options.sh
> +++ b/t/t3436-rebase-more-options.sh
> @@ -134,6 +134,63 @@ test_expect_success '--committer-date-is-author-date works when committing confl
>         test_cmp expect actual
>  '
>
> +# Checking for +0000 in author time is enough since default
> +# timezone is UTC, but the timezone used while committing
> +# sets to +0530.
> +test_expect_success '--ignore-date works with apply backend' '
> +       git commit --amend --date="$GIT_AUTHOR_DATE" &&
> +       git rebase --apply --ignore-date HEAD^ &&
> +       git log -1 --pretty="format:%ai" >authortime &&
> +       grep "+0000" authortime
> +'
> +
> +test_expect_success '--ignore-date works with merge backend' '
> +       git commit --amend --date="$GIT_AUTHOR_DATE" &&
> +       git rebase --ignore-date -m HEAD^ &&
> +       git log -1 --pretty="format:%ai" >authortime &&
> +       grep "+0000" authortime
> +'
> +
> +test_expect_success '--ignore-date works after conflict resolution' '
> +       test_must_fail git rebase --ignore-date -m \
> +               --onto commit2^^ commit2^ commit2 &&
> +       echo resolved >foo &&
> +       git add foo &&
> +       git rebase --continue &&
> +       git log --pretty=%ai >authortime &&
> +       grep +0000 authortime
> +'
> +
> +test_expect_success '--ignore-date works with rebase -r' '
> +       git checkout side &&
> +       git merge --no-ff commit3 &&
> +       git rebase -r --root --ignore-date &&
> +       git log --pretty=%ai >authortime &&
> +       ! grep -v "+0000" authortime
> +'
> +
> +test_expect_success '--ignore-date with --committer-date-is-author-date works' '
> +       test_must_fail git rebase -m --committer-date-is-author-date \
> +               --ignore-date --onto commit2^^ commit2^ commit3 &&
> +       git checkout --theirs foo &&
> +       git add foo &&
> +       git rebase --continue &&
> +       git log -2 --pretty=%ai >authortime &&
> +       git log -2 --pretty=%ci >committertime &&
> +       test_cmp authortime committertime &&
> +       ! grep -v "+0000" authortime
> +'
> +
> +test_expect_success '--ignore-date --committer-date-is-author-date works when forking merge' '
> +       GIT_SEQUENCE_EDITOR="echo \"merge -C $(git rev-parse HEAD) commit3\">" \
> +               git rebase -i --strategy=resolve --ignore-date \
> +               --committer-date-is-author-date side side &&
> +       git log -1 --pretty=%ai >authortime &&
> +       git log -1 --pretty=%ci >committertime &&
> +       test_cmp authortime committertime &&
> +       grep "+0000" authortime
> + '
> +
>  # This must be the last test in this file
>  test_expect_success '$EDITOR and friends are unchanged' '
>         test_editor_unchanged
> --
> 2.26.2

Same question here as for patch 2 -- does it rely on us forking a "git
commit" subprocess which reads from the environment variable, or does
our try_to_commit() (which I'd rather we used in all cases) also work
with the environment variable?

Didn't notice any other problems or questions while reading over the patch.