Inspect: create a full comparison output if exu is required and diffs are present

Summary: No exu is created if no diffs have been found. However, if diffs are present, we append all the comparison images, including those which don't have differences.

Differential Revision: https://phab.enlightenment.org/D7355

src/bin/inspect.c

@@ -1505,6 +1505,7 @@ main(int argc, char *argv[])
      {
         const char *out_ext = strrchr(output, '.');
         Exactness_Unit *unit1 = NULL, *unit2 = NULL, *unitO = NULL;
+        int nb_diffs = 0;
         Eina_List *itr1, *itr2;
         EINA_LIST_FOREACH(_units, itr1, unit)
           {
@@ -1534,8 +1535,10 @@ main(int argc, char *argv[])
              Exactness_Image *ex_img1 = itr1 ? eina_list_data_get(itr1) : NULL;
              Exactness_Image *ex_img2 = itr2 ? eina_list_data_get(itr2) : NULL;
              Exactness_Image *ex_imgO = NULL;
-             if (exactness_image_compare(ex_img1, ex_img2, &ex_imgO))
+             Eina_Bool has_diff = exactness_image_compare(ex_img1, ex_img2, &ex_imgO);
+             if (has_diff || !strcmp(out_ext, ".exu"))
                {
+                  if (has_diff) nb_diffs++;
                   if (!unitO) unitO = calloc(1, sizeof(*unitO));
                   unitO->imgs = eina_list_append(unitO->imgs, ex_imgO);
                   unitO->nb_shots++;
@@ -1564,7 +1567,7 @@ main(int argc, char *argv[])
         else if (!strcmp(out_ext, ".exu"))
           {
              _diff_result_print(unit1, unit2);
-             if (unitO) exactness_unit_file_write(unitO, output);
+             if (nb_diffs) exactness_unit_file_write(unitO, output);
              else ret = 0;
           }
         else