diff --git a/src/libpsc/tests/test_bnd.cxx b/src/libpsc/tests/test_bnd.cxx
index 18eb790ea..a76ac3767 100644
--- a/src/libpsc/tests/test_bnd.cxx
+++ b/src/libpsc/tests/test_bnd.cxx
@@ -247,9 +247,7 @@ TYPED_TEST(BndTest, AddGhosts)
     for (int p = 0; p < mflds.n_patches(); p++) {
       auto flds = make_Fields3d<dim_xyz>(
         h_mflds.view(_all, _all, _all, _all, p), -grid.ibn);
-      int i0 = grid.patches[p].off[0];
-      int j0 = grid.patches[p].off[1];
-      int k0 = grid.patches[p].off[2];
+
       grid.Foreach_3d(B, B, [&](int i, int j, int k) { flds(0, i, j, k) = 1; });
     }
     gt::copy(h_mflds, mflds.storage());
@@ -264,30 +262,37 @@ TYPED_TEST(BndTest, AddGhosts)
   {
     auto&& h_mflds = gt::host_mirror(mflds.storage());
     gt::copy(mflds.storage(), h_mflds);
+
     for (int p = 0; p < mflds.n_patches(); p++) {
       auto flds = make_Fields3d<dim_xyz>(
         h_mflds.view(_all, _all, _all, _all, p), -grid.ibn);
       int j0 = grid.patches[p].off[1];
       int k0 = grid.patches[p].off[2];
       auto& ldims = grid.ldims;
+
       grid.Foreach_3d(B, B, [&](int i, int j, int k) {
-        int n_nei = 0;
+        int n_neighbors_x = 0;
+        int n_neighbors_y = 0;
+        int n_neighbors_z = 0;
+
         if (i >= 0 && i < ldims[0] && j >= 0 && j < ldims[1] && k >= 0 &&
             k < ldims[2]) {
           if (!dim::InvarX::value) {
-            if (i < B || i >= ldims[0] - B)
-              n_nei++;
+            n_neighbors_x += i < B;
+            n_neighbors_x += i >= ldims[0] - B;
           }
-          if (j < B || j >= ldims[1] - B)
-            n_nei++;
-          if (k < B || k >= ldims[2] - B)
-            n_nei++;
-          if (n_nei == 2)
-            n_nei = 3; // edge -> diagonal contribution, too
-          else if (n_nei == 3)
-            n_nei = 11; // corner -> why? FIXME why not 7?
+
+          n_neighbors_y += j < B;
+          n_neighbors_y += j >= ldims[1] - B;
+
+          n_neighbors_z += k < B;
+          n_neighbors_z += k >= ldims[2] - B;
         }
-        EXPECT_EQ(flds(0, i, j, k), 1 + n_nei)
+
+        int n_neighbors =
+          (n_neighbors_x + 1) * (n_neighbors_y + 1) * (n_neighbors_z + 1) - 1;
+
+        EXPECT_EQ(flds(0, i, j, k), 1 + n_neighbors)
           << "ijk " << i << " " << j << " " << k;
       });
     }