fixup! p5313: add size comparison test

Update to the latest iteration of gitgitgadget#1785.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

t/perf/p5313-pack-objects.sh

@@ -25,47 +25,49 @@ test_perf 'thin pack' '
 '
 
 test_size 'thin pack size' '
-	wc -c <out
+	test_file_size out
 '
 
 test_perf 'thin pack with --full-name-hash' '
 	git pack-objects --thin --stdout --revs --sparse --full-name-hash <in-thin >out
 '
 
 test_size 'thin pack size with --full-name-hash' '
-	wc -c <out
+	test_file_size out
 '
 
 test_perf 'big pack' '
 	git pack-objects --stdout --revs --sparse  <in-big >out
 '
 
 test_size 'big pack size' '
-	wc -c <out
+	test_file_size out
 '
 
 test_perf 'big pack with --full-name-hash' '
 	git pack-objects --stdout --revs --sparse --full-name-hash <in-big >out
 '
 
 test_size 'big pack size with --full-name-hash' '
-	wc -c <out
+	test_file_size out
 '
 
 test_perf 'repack' '
 	git repack -adf
 '
 
 test_size 'repack size' '
-	wc -c <.git/objects/pack/pack-*.pack
+	pack=$(ls .git/objects/pack/pack-*.pack) &&
+	test_file_size "$pack"
 '
 
 test_perf 'repack with --full-name-hash' '
 	git repack -adf --full-name-hash
 '
 
 test_size 'repack size with --full-name-hash' '
-	wc -c <.git/objects/pack/pack-*.pack
+	pack=$(ls .git/objects/pack/pack-*.pack) &&
+	test_file_size "$pack"
 '
 
 test_done