If there is a loose reference file with invalid contents, "git
for-each-ref" incorrectly reports the problem as being a missing
object with name NULL_SHA1:
$ echo '12345678' >.git/refs/heads/nonsense
$ git for-each-ref
fatal: missing object 0000000000000000000000000000000000000000 for refs/heads/nonsense
With an explicit "--format" string, it can even report that the
reference validly points at NULL_SHA1:
$ git for-each-ref --format='%(objectname) %(refname)'
0000000000000000000000000000000000000000 refs/heads/nonsense
$ echo $?
0
This has been broken since
b7dd2d2 for-each-ref: Do not lookup objects when they will not be used (2009-05-27)
, which changed for-each-ref from using for_each_ref() to using
git_for_each_rawref() in order to avoid looking up the referred-to
objects unnecessarily. (When "git for-each-ref" is given a "--format"
string that doesn't include information about the pointed-to object,
it does not look up the object at all, which makes it considerably
faster. Iterating with DO_FOR_EACH_INCLUDE_BROKEN is essential to this
optimization because otherwise for_each_ref() would itself need to
check whether the object exists as part of its brokenness test.)
But for_each_rawref() includes broken references in the iteration, and
"git for-each-ref" doesn't itself reject references with REF_ISBROKEN.
The result is that broken references are processed *as if* they had
the value NULL_SHA1, which is the value stored in entries for broken
references.
Change "git for-each-ref" to emit warnings for references that are
REF_ISBROKEN but to otherwise skip them.
Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
8afc493d11