diff options
| -rw-r--r-- | doc/release/upcoming_changes/15900.deprecation.rst | 16 | ||||
| -rw-r--r-- | numpy/core/src/multiarray/mapping.c | 55 | ||||
| -rw-r--r-- | numpy/core/tests/test_deprecations.py | 27 |
3 files changed, 89 insertions, 9 deletions
diff --git a/doc/release/upcoming_changes/15900.deprecation.rst b/doc/release/upcoming_changes/15900.deprecation.rst new file mode 100644 index 000000000..22be711d0 --- /dev/null +++ b/doc/release/upcoming_changes/15900.deprecation.rst @@ -0,0 +1,16 @@ +Indexing errors will be reported even when index result is empty +---------------------------------------------------------------- +In the future, NumPy will raise an IndexError when an +integer array index contains out of bound values even if a non-indexed +dimension is of length 0. This will now emit a DeprecationWarning. +This can happen when the array is previously empty, or an empty +slice is involved:: + + arr1 = np.zeros((5, 0)) + arr1[[20]] + arr2 = np.zeros((5, 5)) + arr2[[20], :0] + +Previously the non-empty index ``[20]`` was not checked for correctness. +It will now be checked causing a deprecation warning which will be turned +into an error. This also applies to assignments. diff --git a/numpy/core/src/multiarray/mapping.c b/numpy/core/src/multiarray/mapping.c index 43dbde2f1..7aefbfc38 100644 --- a/numpy/core/src/multiarray/mapping.c +++ b/numpy/core/src/multiarray/mapping.c @@ -1655,11 +1655,12 @@ array_subscript(PyArrayObject *self, PyObject *op) goto finish; } - if (mit->numiter > 1) { + if (mit->numiter > 1 || mit->size == 0) { /* * If it is one, the inner loop checks indices, otherwise * check indices beforehand, because it is much faster if - * broadcasting occurs and most likely no big overhead + * broadcasting occurs and most likely no big overhead. + * The inner loop optimization skips index checks for size == 0 though. */ if (PyArray_MapIterCheckIndices(mit) < 0) { goto finish; @@ -2479,13 +2480,19 @@ PyArray_MapIterCheckIndices(PyArrayMapIterObject *mit) int i; NPY_BEGIN_THREADS_DEF; - if (mit->size == 0) { - /* All indices got broadcast away, do *not* check as it always was */ + intp_type = PyArray_DescrFromType(NPY_INTP); + + if (NpyIter_GetIterSize(mit->outer) == 0) { + /* + * When the outer iteration is empty, the indices broadcast to an + * empty shape, and in this case we do not check if there are out + * of bounds indices. + * The code below does use the indices without broadcasting since + * broadcasting only repeats values. + */ return 0; } - intp_type = PyArray_DescrFromType(NPY_INTP); - NPY_BEGIN_THREADS; for (i=0; i < mit->numiter; i++) { @@ -2515,7 +2522,7 @@ PyArray_MapIterCheckIndices(PyArrayMapIterObject *mit) if (check_and_adjust_index(&indval, outer_dim, outer_axis, _save) < 0) { Py_DECREF(intp_type); - return -1; + goto indexing_error; } data += stride; } @@ -2528,13 +2535,17 @@ PyArray_MapIterCheckIndices(PyArrayMapIterObject *mit) op_iter = NpyIter_New(op, NPY_ITER_BUFFERED | NPY_ITER_NBO | NPY_ITER_ALIGNED | NPY_ITER_EXTERNAL_LOOP | NPY_ITER_GROWINNER | - NPY_ITER_READONLY, + NPY_ITER_READONLY | NPY_ITER_ZEROSIZE_OK, NPY_KEEPORDER, NPY_SAME_KIND_CASTING, intp_type); if (op_iter == NULL) { Py_DECREF(intp_type); return -1; } + if (NpyIter_GetIterSize(op_iter) == 0) { + NpyIter_Deallocate(op_iter); + continue; + } op_iternext = NpyIter_GetIterNext(op_iter, NULL); if (op_iternext == NULL) { @@ -2554,7 +2565,7 @@ PyArray_MapIterCheckIndices(PyArrayMapIterObject *mit) outer_dim, outer_axis, _save) < 0) { Py_DECREF(intp_type); NpyIter_Deallocate(op_iter); - return -1; + goto indexing_error; } *iterptr += *iterstride; } @@ -2567,6 +2578,32 @@ PyArray_MapIterCheckIndices(PyArrayMapIterObject *mit) NPY_END_THREADS; Py_DECREF(intp_type); return 0; + +indexing_error: + + if (mit->size == 0) { + PyObject *err_type = NULL, *err_value = NULL, *err_traceback = NULL; + PyErr_Fetch(&err_type, &err_value, &err_traceback); + /* 2020-05-27, NumPy 1.20 */ + if (DEPRECATE( + "Out of bound index found. This was previously ignored " + "when the indexing result contained no elements. " + "In the future the index error will be raised. This error " + "occurs either due to an empty slice, or if an array has zero " + "elements even before indexing.\n" + "(Use `warnings.simplefilter('error')` to turn this " + "DeprecationWarning into an error and get more details on " + "the invalid index.)") < 0) { + npy_PyErr_ChainExceptions(err_type, err_value, err_traceback); + return -1; + } + Py_DECREF(err_type); + Py_DECREF(err_value); + Py_XDECREF(err_traceback); + return 0; + } + + return -1; } diff --git a/numpy/core/tests/test_deprecations.py b/numpy/core/tests/test_deprecations.py index 82d24e0f7..523638a35 100644 --- a/numpy/core/tests/test_deprecations.py +++ b/numpy/core/tests/test_deprecations.py @@ -618,3 +618,30 @@ class BuiltInRoundComplexDType(_DeprecationTestCase): self.assert_not_deprecated(round, args=(scalar,)) self.assert_not_deprecated(round, args=(scalar, 0)) self.assert_not_deprecated(round, args=(scalar,), kwargs={'ndigits': 0}) + + +class TestIncorrectAdvancedIndexWithEmptyResult(_DeprecationTestCase): + # 2020-05-27, NumPy 1.20.0 + message = "Out of bound index found. This was previously ignored.*" + + @pytest.mark.parametrize("index", [([3, 0],), ([0, 0], [3, 0])]) + def test_empty_subspace(self, index): + # Test for both a single and two/multiple advanced indices. These + # This will raise an IndexError in the future. + arr = np.ones((2, 2, 0)) + self.assert_deprecated(arr.__getitem__, args=(index,)) + self.assert_deprecated(arr.__setitem__, args=(index, 0.)) + + # for this array, the subspace is only empty after applying the slice + arr2 = np.ones((2, 2, 1)) + index2 = (slice(0, 0),) + index + self.assert_deprecated(arr2.__getitem__, args=(index2,)) + self.assert_deprecated(arr2.__setitem__, args=(index2, 0.)) + + def test_empty_index_broadcast_not_deprecated(self): + arr = np.ones((2, 2, 2)) + + index = ([[3], [2]], []) # broadcast to an empty result. + self.assert_not_deprecated(arr.__getitem__, args=(index,)) + self.assert_not_deprecated(arr.__setitem__, + args=(index, np.empty((2, 0, 2)))) |