Do not expose the schunk attribute on LazyExpr

src/blosc2/lazyexpr.py

@@ -2014,7 +2014,6 @@ def _open_lazyarray(array):
     if isinstance(expr, blosc2.LazyExpr):
         # Make the array info available for the user (only available when opened from disk)
         expr.array = array
-        expr.schunk = array.schunk
     elif isinstance(expr, np.ndarray):
         # The expression was evaluated immediately
         expr = blosc2.asarray(expr)

tests/ndarray/test_lazyexpr.py

@@ -503,6 +503,11 @@ def test_save():
     np.testing.assert_allclose(res[:], nres, rtol=tol, atol=tol)
 
     expr = blosc2.open(urlpath_save)
+    # After opening, check that a lazy expression does have an array attribute,
+    # but does not have a schunk one. This is by design, and because some packages
+    # (e.g. Caterva2), might assume that a LazyExpr does not have a schunk attribute.
+    assert hasattr(expr, "array") is True
+    assert hasattr(expr, "schunk") is False
     # Check the dtype (should be upcasted to float64)
     assert expr.array.dtype == np.float64
     res = expr.compute()