t5538: confirm deltas in shallow pushes

It can be notoriously difficult to detect if delta bases are being
computed properly during 'git push'. Construct an example where it will
make a kilobyte worth of difference when a delta base is not found. We
can then use the progress indicators to distinguish between bytes and
KiB depending on whether the delta base is found and used.

Signed-off-by: Derrick Stolee <[email protected]>

Author: derrickstolee

t/t5538-push-shallow.sh

@@ -150,6 +150,8 @@ test_expect_success 'push new commit from shallow clone has good deltas' '
 	GIT_TRACE2_PERF="$(pwd)/trace.txt" \
 	GIT_PROGRESS_DELAY=0 git -C deltas push --progress origin deltas 2>err &&
 
+	test_grep "Enumerating objects: 5, done" err &&
+
 	# If the delta base is found, then this message uses "bytes".
 	# If the delta base is not found, then this message uses "KiB".
 	test_grep "Writing objects: .* bytes" err