diff --git a/glib/tests/fileutils.c b/glib/tests/fileutils.c
index 32f46a041..8816fd56c 100644
--- a/glib/tests/fileutils.c
+++ b/glib/tests/fileutils.c
@@ -509,6 +509,17 @@ test_format_size_for_display (void)
   check_string (g_format_size (1000 * 1000), "1.0 MB");
   check_string (g_format_size (1000 * 1000 * 1000), "1.0 GB");
 
+  check_string (g_format_size_full (0, G_FORMAT_SIZE_IEC_UNITS), "0 bytes");
+  check_string (g_format_size_full (1, G_FORMAT_SIZE_IEC_UNITS), "1 byte");
+  check_string (g_format_size_full (2, G_FORMAT_SIZE_IEC_UNITS), "2 bytes");
+
+  check_string (g_format_size_full (2048ULL, G_FORMAT_SIZE_IEC_UNITS), "2.0 KiB");
+  check_string (g_format_size_full (2048ULL * 1024, G_FORMAT_SIZE_IEC_UNITS), "2.0 MiB");
+  check_string (g_format_size_full (2048ULL * 1024 * 1024, G_FORMAT_SIZE_IEC_UNITS), "2.0 GiB");
+  check_string (g_format_size_full (2048ULL * 1024 * 1024 * 1024, G_FORMAT_SIZE_IEC_UNITS), "2.0 TiB");
+  check_string (g_format_size_full (2048ULL * 1024 * 1024 * 1024 * 1024, G_FORMAT_SIZE_IEC_UNITS), "2.0 PiB");
+  check_string (g_format_size_full (2048ULL * 1024 * 1024 * 1024 * 1024 * 1024, G_FORMAT_SIZE_IEC_UNITS), "2.0 EiB");
+
   check_string (g_format_size_full (238472938, G_FORMAT_SIZE_IEC_UNITS), "227.4 MiB");
   check_string (g_format_size_full (238472938, G_FORMAT_SIZE_DEFAULT), "238.5 MB");
   check_string (g_format_size_full (238472938, G_FORMAT_SIZE_LONG_FORMAT), "238.5 MB (238472938 bytes)");