Merge branch 'rs/empty-archive'

Fixes tests added in 1.8.2 era that are broken on BSDs.

* rs/empty-archive:
t5004: resurrect original empty tar archive test
t5004: avoid using tar for checking emptiness of archive

diff --cc t/t5004-archive-corner-cases.sh
index 8d1bbd356ac9a22021db0cdbd14544fbcf3c9246,f25f06b02209fbf72b9022a21d8ab9a90cb6628b..67f3b54bed3545417d1f6186f6f42452cb55dc87
--- 1/t/t5004-archive-corner-cases.sh
--- 2/t/t5004-archive-corner-cases.sh
+++ b/t/t5004-archive-corner-cases.sh
@@@ -27,6 -27,20 +27,21 @@@ check_dir() 
        test_cmp expect actual
  }
  
++
+ # bsdtar/libarchive versions before 3.1.3 consider a tar file with a
+ # global pax header that is not followed by a file record as corrupt.
+ if "$TAR" tf "$TEST_DIRECTORY"/t5004/empty-with-pax-header.tar >/dev/null 2>&1
+ then
+       test_set_prereq HEADER_ONLY_TAR_OK
+ fi
+ 
+ test_expect_success HEADER_ONLY_TAR_OK 'tar archive of commit with empty tree' '
+       git archive --format=tar HEAD >empty-with-pax-header.tar &&
+       make_dir extract &&
+       "$TAR" xf empty-with-pax-header.tar -C extract &&
+       check_dir extract
+ '
+ 
  test_expect_success 'tar archive of empty tree is empty' '
        git archive --format=tar HEAD: >empty.tar &&
        perl -e "print \"\\0\" x 10240" >10knuls.tar &&