Merge 8917a1e9b3 into f7e14e985b

include/pybind11/numpy.h

@@ -1232,9 +1232,7 @@ public:
     // Reference to element at a given index
     template <typename... Ix>
     const T &at(Ix... index) const {
-        if ((ssize_t) sizeof...(index) != ndim()) {
-            fail_dim_check(sizeof...(index), "index dimension mismatch");
-        }
+        check_rank_precondition(sizeof...(index));
         return *(static_cast<const T *>(array::data())
                  + byte_offset(ssize_t(index)...) / itemsize());
     }
@@ -1242,13 +1240,33 @@ public:
     // Mutable reference to element at a given index
     template <typename... Ix>
     T &mutable_at(Ix... index) {
-        if ((ssize_t) sizeof...(index) != ndim()) {
-            fail_dim_check(sizeof...(index), "index dimension mismatch");
-        }
+        check_rank_precondition(sizeof...(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_rank_precondition(sizeof...(index));
+        check_dimensions(index...);
+#endif
+        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_rank_precondition(sizeof...(index));
+        check_dimensions(index...);
+#endif
+        return *(static_cast<T *>(array::mutable_data())
+                 + detail::byte_offset_unsafe(strides(), ssize_t(index)...) / itemsize());
+    }
+
     /**
      * Returns a proxy object that provides access to the array's data without bounds or
      * dimensionality checking.  Will throw if the array is missing the `writeable` flag.  Use with
@@ -1305,6 +1323,13 @@ protected:
                                                            | ExtraFlags,
                                                        nullptr);
     }
+
+private:
+    void check_rank_precondition(ssize_t dim) const {
+        if (dim != ndim()) {
+            fail_dim_check(dim, "index dimension mismatch");
+        }
+    }
 };
 
 template <typename T>

tests/test_numpy_array.cpp

@@ -131,6 +131,15 @@ arr_t &mutate_at_t(arr_t &a, Ix... idx) {
     a.mutable_at(idx...)++;
     return a;
 }
+template <typename... Ix>
+arr_t &subscript_via_call_operator_t(arr_t &a, Ix... idx) {
+    a(idx...)++;
+    return a;
+}
+template <typename... Ix>
+py::ssize_t const_subscript_via_call_operator_t(const arr_t &a, Ix... idx) {
+    return a(idx...);
+}
 
 #define def_index_fn(name, type)                                                                  \
     sm.def(#name, [](type a) { return name(a); });                                                \
@@ -197,6 +206,13 @@ TEST_SUBMODULE(numpy_array, sm) {
     sm.def("nbytes", [](const arr &a) { return a.nbytes(); });
     sm.def("owndata", [](const arr &a) { return a.owndata(); });
 
+    sm.attr("defined_NDEBUG") =
+#ifdef NDEBUG
+        true;
+#else
+        false;
+#endif
+
     // test_index_offset
     def_index_fn(index_at, const arr &);
     def_index_fn(index_at_t, const arr_t &);
@@ -210,6 +226,8 @@ TEST_SUBMODULE(numpy_array, sm) {
     def_index_fn(mutate_data_t, arr_t &);
     def_index_fn(at_t, const arr_t &);
     def_index_fn(mutate_at_t, arr_t &);
+    def_index_fn(subscript_via_call_operator_t, arr_t &);
+    def_index_fn(const_subscript_via_call_operator_t, const arr_t &);
 
     // test_make_c_f_array
     sm.def("make_f_array", [] { return py::array_t<float>({2, 2}, {4, 8}); });

tests/test_numpy_array.py

@@ -111,20 +111,32 @@ def test_data(arr, args, ret):
     assert all(m.data(arr, *args)[(1 if byteorder == "little" else 0) :: 2] == 0)
 
 
+@pytest.mark.parametrize(
+    "func",
+    [
+        m.at_t,
+        m.mutate_at_t,
+        m.const_subscript_via_call_operator_t,
+        m.subscript_via_call_operator_t,
+    ][: 2 if m.defined_NDEBUG else 99],
+)
 @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)"
+def test_elem_reference(arr, func, dim):
+    with pytest.raises(IndexError) as excinfo:
+        func(arr, *([0] * dim))
+    assert str(excinfo.value) == f"index dimension mismatch: {dim} (ndim = 2)"
 
 
-def test_at(arr):
-    assert m.at_t(arr, 0, 2) == 3
-    assert m.at_t(arr, 1, 0) == 4
+@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
+    assert func(arr, 1, 0) == 4
 
-    assert all(m.mutate_at_t(arr, 0, 2).ravel() == [1, 2, 4, 4, 5, 6])
-    assert all(m.mutate_at_t(arr, 1, 0).ravel() == [1, 2, 4, 5, 5, 6])
+
+@pytest.mark.parametrize("func", [m.mutate_at_t, m.subscript_via_call_operator_t])
+def test_mutable_elem_reference(arr, func):
+    assert all(func(arr, 0, 2).ravel() == [1, 2, 4, 4, 5, 6])
+    assert all(func(arr, 1, 0).ravel() == [1, 2, 4, 5, 5, 6])
 
 
 def test_mutate_readonly(arr):
@@ -153,8 +165,9 @@ 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):
-    for func in (
+@pytest.mark.parametrize(
+    "func",
+    [
         m.index_at,
         m.index_at_t,
         m.data,
@@ -163,13 +176,17 @@ def test_bounds_check(arr):
         m.mutate_data_t,
         m.at_t,
         m.mutate_at_t,
-    ):
-        with pytest.raises(IndexError) as excinfo:
-            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"
+        m.const_subscript_via_call_operator_t,
+        m.subscript_via_call_operator_t,
+    ][: 8 if m.defined_NDEBUG else 99],
+)
+def test_bounds_check(arr, func):
+    with pytest.raises(IndexError) as excinfo:
+        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():