[PATCH v3 0/3] rev-parse: allow --flags to output rev-parse-like flags

This series allows git rev-parse --flags to output remaining flag-like arguments even if such arguments are valid options to git rev-parse itself.

Previously:
  $ git rev-parse --flags -q -X --no-flags -- Y -Z
  -X
  $

Now:
  $ git rev-parse --flags -q -X --no-flags -- Y -Z
  -q -X --no-flags
  $

Note existing behaviour was:
  $ git rev-parse --flags HEAD
  HEAD
  $

This behaviour is unchanged by this series, but the documentation has
been updated to state that --flags:
  Do not output non-flag parameters which are not also revisions.

Reviewers are invited to comment on whether current behaviour is reasonable or whether the implementation should be changed to match the current documentation. That is, to make the behaviour:

  $ git rev-parse --flags HEAD
  $ 

This series differs from v2 in that 2/4 of the previous series was actually unnecesssary since --no-flags --flags -X already produced no output. The documentation has been reworded to relect current behaviour more accurately.

Aevar's feedback has been incorporated.

Jon Seymour (3):
  rev-parse: stop interpreting flags as options to rev-parse once
    --flags is specified
  rev-parse: add tests for git rev-parse --flags.
  rev-parse: update documentation of --flags and --no-flags options

 Documentation/git-rev-parse.txt |   14 ++++-
 builtin/rev-parse.c             |    8 +++
 t/t1510-rev-parse-flags.sh      |  109 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 129 insertions(+), 2 deletions(-)
 create mode 100755 t/t1510-rev-parse-flags.sh