"$(echo_without_newline "$batch_check_input" | git cat-file --batch-check)"
'
+test_expect_success 'setup blobs which are likely to delta' '
+ test-genrandom foo 10240 >foo &&
+ { cat foo; echo plus; } >foo-plus &&
+ git add foo foo-plus &&
+ git commit -m foo &&
+ cat >blobs <<-\EOF
+ HEAD:foo
+ HEAD:foo-plus
+ EOF
+'
+
+test_expect_success 'confirm that neither loose blob is a delta' '
+ cat >expect <<-EOF
+ $_z40
+ $_z40
+ EOF
+ git cat-file --batch-check="%(deltabase)" <blobs >actual &&
+ test_cmp expect actual
+'
+
+# To avoid relying too much on the current delta heuristics,
+# we will check only that one of the two objects is a delta
+# against the other, but not the order. We can do so by just
+# asking for the base of both, and checking whether either
+# sha1 appears in the output.
+test_expect_success '%(deltabase) reports packed delta bases' '
+ git repack -ad &&
+ git cat-file --batch-check="%(deltabase)" <blobs >actual &&
+ {
+ grep "$(git rev-parse HEAD:foo)" actual ||
+ grep "$(git rev-parse HEAD:foo-plus)" actual
+ }
+'
+
test_done