[PATCH v5 0/8] Improvements to sha1_file

[Jonathan Tan <jonathantanmy@google.com>]

Thanks, Junio. A reply to your comment on patch 7:

> ... this "if" statement feels like a maintenance nightmare.  The
> intent of the guard, I think, is "when the call wants absolutely
> nothing but whence", but the implementation of the guard will not
> stay true to the intent whenever somebody adds a new field to oi.
> 
> I wonder if it makes more sense to have a new field "whence_only",
> which is set only by such a specialized caller, which this guard
> checks (and no other fields).

After some more thought, I think I came up with a better solution -
allow sha1_object_info_extended() to take a NULL struct object_info
pointer, and immediately assign it (if NULL) a blank struct, but use the
NULL-ness as an indication that we can skip accessing the packfile. The
last patch actually doesn't even need the "whence", so we can do this.

Changes from v4:
 - patch 2
   - Updated commit message to explain why
     OBJECT_INFO_ALLOW_UNKNOWN_TYPE is defined to be 2, not 1.
 - patch 3
   - Made all invocations of sha1_object_info_extended() compare "< 0".
 - patch 5
   - Made all invocations of sha1_object_info_extended() compare "< 0".
 - patch 7
   - Rewrote patch to make sha1_object_info_extended() accept NULL
     struct object_info pointer.
 - patch 8
   - Made has_sha1_file_with_flags send NULL instead of blank struct
     object_info.

Jonathan Tan (8):
  sha1_file: teach packed_object_info about typename
  sha1_file: rename LOOKUP_UNKNOWN_OBJECT
  sha1_file: rename LOOKUP_REPLACE_OBJECT
  sha1_file: move delta base cache code up
  sha1_file: refactor read_object
  sha1_file: improve sha1_object_info_extended
  sha1_file: do not access pack if unneeded
  sha1_file: refactor has_sha1_file_with_flags

 builtin/cat-file.c   |   7 +-
 builtin/fetch.c      |  10 +-
 builtin/index-pack.c |   3 +-
 cache.h              |  36 +++--
 sha1_file.c          | 385 ++++++++++++++++++++++++++-------------------------
 5 files changed, 224 insertions(+), 217 deletions(-)

-- 
2.13.1.611.g7e3b11ae1-goog