[PATCH 00/19] Add --all option to git-check-attr

Currently it is possible to inquire the values of particular attributes on particular files, using either the API function git_checkattr() or the command "git check-attr". But it is not possible to ask for *all* attributes that are associated with a particular file. This patch series adds that functionality:

* A new API call git_allattr()

* A new option "git check-attr --all -- pathnames"

Along the way, several small cleanups are made in the general neighborhood, including:

* Disallow the empty string as an attribute name

* Provide access to the name attribute of git_attr

* Fail with an error message if no pathnames are provided on the
  command line (and --stdin is not used)

* If --stdin is used, interpret all command-line arguments as
  attribute names

* Rename struct git_attr_check to git_attr_value

Most of the patches are hopefully self-explanatory; see the individual patch emails for discussion of changes that might potentially be controversial.

Michael Haggerty (19):
  doc: Add a link from gitattributes(5) to git-check-attr(1)
  doc: Correct git_attr() calls in example code
  Remove anachronism from comment
  Disallow the empty string as an attribute name
  git-check-attr: Add missing "&&"
  git-check-attr: Add tests of command-line parsing
  Provide access to the name attribute of git_attr
  git-check-attr: Use git_attr_name()
  Allow querying all attributes on a file
  git-check-attr: Extract a function output_attr()
  git-check-attr: Introduce a new variable
  git-check-attr: Extract a function error_with_usage()
  git-check-attr: Handle each error separately
  git-check-attr: Process command-line args more systematically
  git-check-attr: Error out if no pathnames are specified
  git-check-attr: Add an --all option to show all attributes
  git-check-attr: Drive two tests using the same raw data
  git-check-attr: Fix command-line handling to match docs
  Rename struct git_attr_check to git_attr_value

 Documentation/git-check-attr.txt              |   23 ++++-
 Documentation/gitattributes.txt               |    3 +
 Documentation/technical/api-gitattributes.txt |   66 +++++++++-----
 archive.c                                     |    4 +-
 attr.c                                        |   61 +++++++++++--
 attr.h                                        |   24 ++++-
 builtin/check-attr.c                          |  123 ++++++++++++++++--------
 builtin/pack-objects.c                        |    4 +-
 convert.c                                     |   10 +-
 ll-merge.c                                    |    6 +-
 t/t0003-attributes.sh                         |   61 +++++++++----
 userdiff.c                                    |    2 +-
 ws.c                                          |    4 +-
 13 files changed, 278 insertions(+), 113 deletions(-)