[PATCH v5 0/6] Send help text from "git cmd -h" to stdout

[Junio C Hamano <gitster@pobox.com>]

Jonas Konrad noticed[*] that "git branch -h" started showing the help
text to the standard error stream.  It turns out that we are fairly
inconsistent in our implementation of "git cmd -h".  The users of
parse-options API will get "If -h is the only option on the command
line, give the help text to the standard output" for free, but some
commands manually check for the condition and then call the
usage_with_options() function, which gives the identical help text
to the standard error stream.  And "git branch -h" Jonas noticed was
one of them.

Older commands written before parse-options API became dominant show
the help text by calling the usage() function, which is meant to be
used when they fail to parse their command line arguments, which has
the same problem.  An explicit request for help text "git cmd -h"
should be fulfilled by showing the help on the standard output.

This series teachs "git $cmd -h" to send its help text to the
standard output stream consistently for built-in commands.

There is a related "what status should these command exit with?"
question, and an argument can be made to switch them to exit with 0,
instead of historical 129, but it is left outside of the series for
now.


Changes since v4:

 - vfdreportf() helper that took a file descriptor has been replaced
   with vfreportf() that takes a FILE * instead, with Peff's help.

[Reference]

https://lore.kernel.org/git/04cfaa3b-847f-4850-9dd6-c1cf9f72807f@uni-muenster.de/

Jeff King (1):
  t0012: optionally check that "-h" output goes to stdout

Junio C Hamano (5):
  parse-options: add show_usage_with_options_if_asked()
  usage: add show_usage_if_asked()
  builtins: send usage_with_options() help text to standard output
  oddballs: send usage() help text to standard output
  builtin: send usage() help text to standard output

 builtin/am.c                |  3 +--
 builtin/branch.c            |  4 ++--
 builtin/check-ref-format.c  |  4 ++--
 builtin/checkout--worker.c  |  6 +++---
 builtin/checkout-index.c    |  6 +++---
 builtin/commit-tree.c       |  4 ++--
 builtin/commit.c            |  8 ++++----
 builtin/credential.c        |  3 ++-
 builtin/diff-files.c        |  3 +--
 builtin/diff-index.c        |  3 +--
 builtin/diff-tree.c         |  3 +--
 builtin/fast-import.c       |  3 +--
 builtin/fetch-pack.c        |  2 ++
 builtin/fsmonitor--daemon.c |  4 ++--
 builtin/gc.c                |  4 ++--
 builtin/get-tar-commit-id.c |  4 +++-
 builtin/index-pack.c        |  3 +--
 builtin/ls-files.c          |  4 ++--
 builtin/mailsplit.c         |  4 ++--
 builtin/merge-index.c       |  7 ++++++-
 builtin/merge-ours.c        |  3 +--
 builtin/merge-recursive.c   |  6 ++++++
 builtin/merge.c             |  4 ++--
 builtin/pack-redundant.c    |  3 +--
 builtin/rebase.c            |  6 +++---
 builtin/remote-ext.c        |  2 ++
 builtin/remote-fd.c         |  1 +
 builtin/rev-list.c          |  3 +--
 builtin/rev-parse.c         |  2 ++
 builtin/unpack-file.c       |  8 ++++++--
 builtin/unpack-objects.c    |  2 ++
 builtin/update-index.c      |  4 ++--
 builtin/upload-archive.c    |  6 +++---
 builtin/var.c               |  1 +
 git-compat-util.h           |  2 ++
 parse-options.c             | 10 ++++++++++
 parse-options.h             |  4 ++++
 t/helper/test-simple-ipc.c  |  4 ++--
 t/t0012-help.sh             |  3 ++-
 t/t7600-merge.sh            |  2 +-
 usage.c                     | 27 ++++++++++++++++++++++++---
 41 files changed, 121 insertions(+), 64 deletions(-)

-- 
2.48.1-218-gc7e8be6a8f