Replace several hard-coded full and partial object IDs with variables or
computed values.  Create junk data to stuff inside an invalid tree that
can be either 20 or 32 bytes long.  Compute a binary all-zeros object ID
instead of hard-coding a 20-byte length.
[...]
Signed-off-by: brian m. carlson <redacted>
---

diff --git a/t/t1450-fsck.sh b/t/t1450-fsck.sh

@@ -9,6 +9,7 @@ test_description='git fsck random collection of tests
 test_expect_success setup '
+       test_oid_init &&
        git config gc.auto 0 &&
        git config i18n.commitencoding ISO-8859-1 &&
        test_commit A fileA one &&

@@ -16,7 +17,8 @@ test_expect_success setup '
        git checkout HEAD^0 &&
        test_commit B fileB two &&
        git tag -d A B &&
-       git reflog expire --expire=now --all
+       git reflog expire --expire=now --all &&
+       test_oid_init
 '