Re: [GSoC][PATCH v2 3/6] rebase -i: support --committer-date-is-author-date

> Hi Rohit
> 
> [...]
>> @@ -964,6 +976,25 @@ static int run_git_commit(struct repository *r,
>>   {
>>       struct child_process cmd = CHILD_PROCESS_INIT;
>> +    if (opts->committer_date_is_author_date) {
>> +        size_t len;
>> +        int res = -1;
>> +        struct strbuf datebuf = STRBUF_INIT;
>> +        char *date = read_author_date_or_null();
> 
> You must always check the return value of functions that might return 
> NULL. In this case we should return an error as you do in try_to 
> _commit() later
> 
>> +
>> +        strbuf_addf(&datebuf, "@%s", date);
> 
> GNU printf() will add something like '(null)' to the buffer if you pass 
> a NULL pointer so I don't think we can be sure that this will not 
> increase the length of the buffer if date is NULL.

> above would be much clearer as well rather than checking len later. What 
> happens if you don't add the '@' at the beginning? (I'm don't know much 
> about git's date handling)
> 
>> +        free(date);
>> +
>> +        date = strbuf_detach(&datebuf, &len);
>> +
>> +        if (len > 1)
>> +            res = setenv("GIT_COMMITTER_DATE", date, 1);
>> +
>> +        free(date);
>> +
>> +        if (res)
>> +            return -1;
>> +    }
>>       if ((flags & CREATE_ROOT_COMMIT) && !(flags & AMEND_MSG)) {
>>           struct strbuf msg = STRBUF_INIT, script = STRBUF_INIT;
>>           const char *author = NULL;
>> @@ -1400,7 +1431,6 @@ static int try_to_commit(struct repository *r,
>>       if (parse_head(r, &current_head))
>>           return -1;
>> -
>>       if (flags & AMEND_MSG) {
>>           const char *exclude_gpgsig[] = { "gpgsig", NULL };
>>           const char *out_enc = get_commit_output_encoding();
>> @@ -1427,6 +1457,21 @@ static int try_to_commit(struct repository *r,
>>           commit_list_insert(current_head, &parents);
>>       }
>> +    if (opts->committer_date_is_author_date) {
>> +        int len = strlen(author);
>> +        struct ident_split ident;
>> +        struct strbuf date = STRBUF_INIT;
>> +
>> +        split_ident_line(&ident, author, len);
>> +
>> +        if (!ident.date_begin)
>> +            return error(_("corrupted author without date 
>> information"));
> 
> We return an error if we cannot get the date - this is exactly what we 
> should be doing above. It is also great to see a single version of this 
> being used whether or not we are amending.
> 
>> +
>> +        strbuf_addf(&date, "@%s",ident.date_begin);
> 
> I think we should use %s.* and ident.date_end to be sure we getting what 
> we want. Your version is OK if the author is formatted correctly but I'm 
> uneasy about relying on that when we can get the verified end from ident.
> 
> Best Wishes
> 
> Phillip
> 
>> +        setenv("GIT_COMMITTER_DATE", date.buf, 1);
>> +        strbuf_release(&date);
>> +    }
>> +
>>       if (write_index_as_tree(&tree, r->index, r->index_file, 0, NULL)) {
>>           res = error(_("git write-tree failed to write a tree"));
>>           goto out;
>> @@ -2542,6 +2587,11 @@ static int read_populate_opts(struct 
>> replay_opts *opts)
>>               opts->signoff = 1;
>>           }
>> +        if (file_exists(rebase_path_cdate_is_adate())) {
>> +            opts->allow_ff = 0;
>> +            opts->committer_date_is_author_date = 1;
>> +        }
>> +
>>           if (file_exists(rebase_path_reschedule_failed_exec()))
>>               opts->reschedule_failed_exec = 1;
>> @@ -2624,6 +2674,8 @@ int write_basic_state(struct replay_opts *opts, 
>> const char *head_name,
>>           write_file(rebase_path_gpg_sign_opt(), "-S%s\n", 
>> opts->gpg_sign);
>>       if (opts->signoff)
>>           write_file(rebase_path_signoff(), "--signoff\n");
>> +    if (opts->committer_date_is_author_date)
>> +        write_file(rebase_path_cdate_is_adate(), "%s", "");
>>       if (opts->reschedule_failed_exec)
>>           write_file(rebase_path_reschedule_failed_exec(), "%s", "");
>> @@ -3821,7 +3873,8 @@ static int pick_commits(struct repository *r,
>>       setenv(GIT_REFLOG_ACTION, action_name(opts), 0);
>>       if (opts->allow_ff)
>>           assert(!(opts->signoff || opts->no_commit ||
>> -                opts->record_origin || opts->edit));
>> +                opts->record_origin || opts->edit ||
>> +                opts->committer_date_is_author_date));
>>       if (read_and_refresh_cache(r, opts))
>>           return -1;
>> diff --git a/sequencer.h b/sequencer.h
>> index 6704acbb9c..e3881e9275 100644
>> --- a/sequencer.h
>> +++ b/sequencer.h
>> @@ -43,6 +43,7 @@ struct replay_opts {
>>       int verbose;
>>       int quiet;
>>       int reschedule_failed_exec;
>> +    int committer_date_is_author_date;
>>       int mainline;
>> diff --git a/t/t3422-rebase-incompatible-options.sh 
>> b/t/t3422-rebase-incompatible-options.sh
>> index 4342f79eea..7402f7e3da 100755
>> --- a/t/t3422-rebase-incompatible-options.sh
>> +++ b/t/t3422-rebase-incompatible-options.sh
>> @@ -61,7 +61,6 @@ test_rebase_am_only () {
>>   }
>>   test_rebase_am_only --whitespace=fix
>> -test_rebase_am_only --committer-date-is-author-date
>>   test_rebase_am_only -C4
>>   test_expect_success REBASE_P '--preserve-merges incompatible with 
>> --signoff' '
>> diff --git a/t/t3433-rebase-options-compatibility.sh 
>> b/t/t3433-rebase-options-compatibility.sh
>> index 2e16e00a9d..b2419a2b75 100755
>> --- a/t/t3433-rebase-options-compatibility.sh
>> +++ b/t/t3433-rebase-options-compatibility.sh
>> @@ -7,6 +7,9 @@ test_description='tests to ensure compatibility 
>> between am and interactive backe
>>   . ./test-lib.sh
>> +GIT_AUTHOR_DATE="1999-04-02T08:03:20+05:30"
>> +export GIT_AUTHOR_DATE
>> +
>>   # This is a special case in which both am and interactive backends
>>   # provide the same output. It was done intentionally because
>>   # both the backends fall short of optimal behaviour.
>> @@ -62,4 +65,20 @@ test_expect_success '--ignore-whitespace works with 
>> interactive backend' '
>>       test_cmp expect file
>>   '
>> +test_expect_success '--committer-date-is-author-date works with am 
>> backend' '
>> +    git commit --amend &&
>> +    git rebase --committer-date-is-author-date HEAD^ &&
>> +    git show HEAD --pretty="format:%ai" >authortime &&
>> +    git show HEAD --pretty="format:%ci" >committertime &&
>> +    test_cmp authortime committertime
>> +'
>> +
>> +test_expect_success '--committer-date-is-author-date works with 
>> interactive backend' '
>> +    git commit --amend &&
>> +    git rebase -i --committer-date-is-author-date HEAD^ &&
>> +    git show HEAD --pretty="format:%ai" >authortime &&
>> +    git show HEAD --pretty="format:%ci" >committertime &&
>> +    test_cmp authortime committertime
>> +'
>> +
>>   test_done
>>