[PATCH v4 0/3] Add mailmap mechanism in cat-file options

Thanks a lot Junio, Taylor and Christian for the review :) I have made the suggested changes.

= Description

At present, `git-cat-file` command with `--batch-check` and `-s` options does not complain when `--use-mailmap` option is given. The latter option is just ignored. Instead, for commit/tag objects, the command should compute the size of the object after replacing the idents and report it. So, this patch series makes `-s` and `--batch-check` options of `git-cat-file` honor mailmap when used with `--use-mailmap` option.

In this patch series we didn't want to change that '%(objectsize)' always shows the size of the original object even when `--use-mailmap` is set because first we have the long term plan to unify how the formats for `git cat-file` and other commands works. And second existing formats like the "pretty formats" used bt `git log` have different options for fields respecting mailmap or not respecting it (%an is for author name while %aN for author name respecting mailmap).

I would like to thank my mentors, Christian Couder and John Cai, for all of their help! Looking forward to the reviews!

= Patch Organization

- The first patch makes `-s` option to return updated size of the
  <commit/tag> object, when combined with `--use-mailmap` option, after
  replacing the idents using the mailmap mechanism.
- The second patch makes `--batch-check` option to return updated size of
  the <commit/tag> object, when combined with `--use-mailmap` option,
  after replacing the idents using the mailmap mechanism.
- The third patch improves the documentation of `-s`, `--batch`,
  `--batch-check` and `--batch-command` options by adding they can be
  combined with `--use-mailmap` options.

= Changes in v4

- Improve the documentation patch to clearly state that the `-s`,
  `--batch-check`, `--batch-command` and `--batch` options can be only
  be used with `--textconv`, `--filters` or `--use-mailmap`.

Siddharth Asthana (3):
  cat-file: add mailmap support to -s option
  cat-file: add mailmap support to --batch-check option
  doc/cat-file: allow --use-mailmap for --batch options

 Documentation/git-cat-file.txt | 53 ++++++++++++++++++++++--------
 builtin/cat-file.c             | 27 ++++++++++++++++
 t/t4203-mailmap.sh             | 59 ++++++++++++++++++++++++++++++++++
 3 files changed, 125 insertions(+), 14 deletions(-)

Range-diff against v3:
1:  38bb89d350 ! 1:  4ae3af37d2 cat-file: add mailmap support to -s option
    @@ Commit message
     
         Mentored-by: Christian Couder <christian.couder@gmail.com>
         Mentored-by: John Cai <johncai86@gmail.com>
    +    Helped-by: Taylor Blau <me@ttaylorr.com>
    +    Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
         Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
     
    - ## Documentation/git-cat-file.txt ##
    -@@ Documentation/git-cat-file.txt: OPTIONS
    - 
    - -s::
    - 	Instead of the content, show the object size identified by
    --	`<object>`.
    -+	`<object>`. If used with `--use-mailmap` option, will show the
    -+	size of updated object after replacing idents using the mailmap
    -+	mechanism.
    - 
    - -e::
    - 	Exit with zero status if `<object>` exists and is a valid
    -
      ## builtin/cat-file.c ##
     @@ builtin/cat-file.c: static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
      
2:  4d49cfde73 ! 2:  a692646228 cat-file: add mailmap support to --batch-check option
    @@ Commit message
     
         Mentored-by: Christian Couder <christian.couder@gmail.com>
         Mentored-by: John Cai <johncai86@gmail.com>
    +    Helped-by: Taylor Blau <me@ttaylorr.com>
    +    Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
         Signed-off-by: Siddharth Asthana <siddharthasthana31@gmail.com>
     
    - ## Documentation/git-cat-file.txt ##
    -@@ Documentation/git-cat-file.txt: OPTIONS
    - 	except `--textconv` or `--filters`, in which case the input lines
    - 	also need to specify the path, separated by whitespace.  See the
    - 	section `BATCH OUTPUT` below for details.
    -+	If used with `--use-mailmap` option, will show the size of
    -+	updated object after replacing idents using the mailmap mechanism.
    - 
    - --batch-check::
    - --batch-check=<format>::
    -
      ## builtin/cat-file.c ##
     @@ builtin/cat-file.c: static void batch_object_write(const char *obj_name,
      	if (!data->skip_object_info) {
-:  ---------- > 3:  41b4650b24 doc/cat-file: allow --use-mailmap for --batch options