Check that chunks/blocks computation does not allow a 0 in blocks

Fixes #165.

blosc2/core.py

@@ -1208,6 +1208,8 @@ def compute_chunks_blocks(shape, chunks=None, blocks=None, dtype=np.uint8, **kwa
         if len(blocks) != len(shape):
             raise ValueError("blocks should have the same length than shape")
         for i in range(len(blocks)):
+            if blocks[i] == 0:
+                raise ValueError("blocks cannot contain 0 dimension")
             if blocks[i] > shape[i]:
                 raise ValueError("blocks cannot be greater than shape")
     if chunks:

tests/ndarray/test_empty.py

@@ -123,3 +123,9 @@ def test_empty_minimal(shape, dtype):
 def test_cparams_chunks_blocks(shape, cparams):
     with pytest.raises(ValueError):
         blosc2.empty(shape, cparams=cparams)
+
+
+def test_zero_in_blockshape():
+    # Check for #165
+    with pytest.raises(ValueError):
+        blosc2.empty(shape=(1200,), chunks=(100,), blocks=(0,))