diff --git a/python/test/unit/graph/test_adjacencylist.py b/python/test/unit/graph/test_adjacencylist.py
index 55165acc3b2..a5bb77fb5a0 100644
--- a/python/test/unit/graph/test_adjacencylist.py
+++ b/python/test/unit/graph/test_adjacencylist.py
@@ -18,3 +18,11 @@ def test_create_adj2d(dtype):
     assert np.array_equal(
         adj.offsets, np.arange(0, num_nodes * num_links + num_links, num_links, dtype=np.int32)
     )
+
+    data = np.arange(20, dtype=dtype)
+    offsets = np.array([0, 5, 15, 20], dtype=np.int32)
+    adj = adjacencylist(data, offsets)
+    assert adj.num_nodes == 3
+    assert len(adj.links(0)) == 5
+    assert len(adj.links(1)) == 10
+    assert len(adj.links(2)) == 5
diff --git a/python/test/unit/la/test_matrix_csr.py b/python/test/unit/la/test_matrix_csr.py
index be44d27d8ff..f9345dc3510 100644
--- a/python/test/unit/la/test_matrix_csr.py
+++ b/python/test/unit/la/test_matrix_csr.py
@@ -144,6 +144,19 @@ def test_distributed_csr(dtype):
     assert np.isclose(mat.data.sum(), pre_final_sum)
 
 
+@pytest.mark.parametrize("dtype", [np.float32, np.float64, np.complex64, np.complex128])
+def test_set_block_matrix(dtype):
+    mesh_dtype = np.real(dtype(0)).dtype
+    ghost_mode = GhostMode.shared_facet
+    mesh = create_unit_square(MPI.COMM_WORLD, 2, 4, ghost_mode=ghost_mode, dtype=mesh_dtype)
+    V = fem.functionspace(mesh, ("Lagrange", 1, (2,)))
+    u, v = ufl.TrialFunction(V), ufl.TestFunction(V)
+    a = fem.form(ufl.inner(u, v) * ufl.dx, dtype=dtype)
+    A = fem.create_matrix(a)
+    As = A.to_scipy(ghosted=True)
+    assert As.blocksize == (2, 2)
+
+
 @pytest.mark.parametrize("dtype", [np.float32, np.float64, np.complex64, np.complex128])
 def test_set_diagonal_distributed(dtype):
     mesh_dtype = np.real(dtype(0)).dtype