add bounds check and test

include/pybind11/numpy.h

@@ -1093,33 +1093,39 @@ public:
     // Reference to element at a given index
     template <typename... Ix>
     const T &at(Ix... index) const {
-        check_dim_precondition(sizeof...(index));
+        check_rank_precondition(sizeof...(index));
-        return const_reference(index...);
+        return *(static_cast<const T *>(array::data())
+                 + byte_offset(ssize_t(index)...) / itemsize());
     }
 
     // Mutable reference to element at a given index
     template <typename... Ix>
     T &mutable_at(Ix... index) {
-        check_dim_precondition(sizeof...(index));
+        check_rank_precondition(sizeof...(index));
-        return mutable_reference(index...);
+        return *(static_cast<T *>(array::mutable_data())
+                 + byte_offset(ssize_t(index)...) / itemsize());
     }
 
     // const-reference to element at a given index without bounds checking
     template <typename... Ix>
     const T &operator()(Ix... index) const {
 #if !defined(NDEBUG)
-        check_dim_precondition(sizeof...(index));
+        check_rank_precondition(sizeof...(index));
+        check_dimensions(index...);
 #endif
-        return const_reference(index...);
+        return *(static_cast<const T *>(array::data())
+                 + detail::byte_offset_unsafe(strides(), ssize_t(index)...) / itemsize());
     }
 
     // mutable reference to element at a given index without bounds checking
     template <typename... Ix>
     T &operator()(Ix... index) {
 #if !defined(NDEBUG)
-        check_dim_precondition(sizeof...(index));
+        check_rank_precondition(sizeof...(index));
+        check_dimensions(index...);
 #endif
-        return mutable_reference(index...);
+        return *(static_cast<T *>(array::mutable_data())
+                 + detail::byte_offset_unsafe(strides(), ssize_t(index)...) / itemsize());
     }
 
     /**
@@ -1180,19 +1186,7 @@ protected:
     }
 
 private:
-    template <typename... Ix>
+    void check_rank_precondition(ssize_t dim) const {
-    const T &const_reference(Ix... index) const {
-        return *(static_cast<const T *>(array::data())
-                 + byte_offset(ssize_t(index)...) / itemsize());
-    }
-
-    template <typename... Ix>
-    T &mutable_reference(Ix... index) {
-        return *(static_cast<T *>(array::mutable_data())
-                 + byte_offset(ssize_t(index)...) / itemsize());
-    }
-
-    void check_dim_precondition(ssize_t dim) const {
         if (dim != ndim()) {
             fail_dim_check(dim, "index dimension mismatch");
         }

tests/test_numpy_array.py

@@ -125,14 +125,6 @@ def test_elem_reference(arr, func, dim):
     assert str(excinfo.value) == f"index dimension mismatch: {dim} (ndim = 2)"
 
 
-# @pytest.mark.parametrize("dim", [0, 1, 3])
-# def test_at_fail(arr, dim):
-#     for func in m.at_t, m.mutate_at_t:
-#         with pytest.raises(IndexError) as excinfo:
-#             func(arr, *([0] * dim))
-#         assert str(excinfo.value) == f"index dimension mismatch: {dim} (ndim = 2)"
-
-
 @pytest.mark.parametrize("func", [m.at_t, m.const_subscript_via_call_operator_t])
 def test_const_elem_reference(arr, func):
     assert func(arr, 0, 2) == 3
@@ -171,8 +163,9 @@ def test_mutate_data(arr):
     assert all(m.mutate_data_t(arr, 1, 2).ravel() == [6, 19, 27, 68, 84, 197])
 
 
-def test_bounds_check(arr):
+@pytest.mark.parametrize(
-    for func in (
+    "func",
+    [
         m.index_at,
         m.index_at_t,
         m.data,
@@ -181,13 +174,17 @@ def test_bounds_check(arr):
         m.mutate_data_t,
         m.at_t,
         m.mutate_at_t,
-    ):
+        m.const_subscript_via_call_operator_t,
-        with pytest.raises(IndexError) as excinfo:
+        m.subscript_via_call_operator_t,
-            func(arr, 2, 0)
+    ][: 8 if m.defined_NDEBUG else 99],
-        assert str(excinfo.value) == "index 2 is out of bounds for axis 0 with size 2"
+)
-        with pytest.raises(IndexError) as excinfo:
+def test_bounds_check(arr, func):
-            func(arr, 0, 4)
+    with pytest.raises(IndexError) as excinfo:
-        assert str(excinfo.value) == "index 4 is out of bounds for axis 1 with size 3"
+        func(arr, 2, 0)
+    assert str(excinfo.value) == "index 2 is out of bounds for axis 0 with size 2"
+    with pytest.raises(IndexError) as excinfo:
+        func(arr, 0, 4)
+    assert str(excinfo.value) == "index 4 is out of bounds for axis 1 with size 3"
 
 
 def test_make_c_f_array():