MAINT: Check operand sizes before doing anything with them

This ensures we do not have to guard against any operand having
fewer dimensions than required by the ufunc in, e.g.,
_parse_axes_argument.

2 files changed, 25 insertions, 17 deletions

diff --git a/numpy/core/src/umath/ufunc_object.c b/numpy/core/src/umath/ufunc_object.c
index 1ffecb1a6..bf5a4ead3 100644
--- a/numpy/core/src/umath/ufunc_object.c
+++ b/numpy/core/src/umath/ufunc_object.c
@@ -1960,19 +1960,6 @@ _get_coredim_sizes(PyUFuncObject *ufunc, PyArrayObject **op,
             int dim_offset = ufunc->core_offsets[i];
             int num_dims = ufunc->core_num_dims[i];
             int core_start_dim = PyArray_NDIM(op[i]) - num_dims;
-
-            /* Check if operands have enough dimensions */
-            if (core_start_dim < 0) {
-                PyErr_Format(PyExc_ValueError,
-                        "%s: %s operand %d does not have enough "
-                        "dimensions (has %d, gufunc core with "
-                        "signature %s requires %d)",
-                        ufunc_get_name_cstr(ufunc), i < nin ? "Input" : "Output",
-                        i < nin ? i : i - nin, PyArray_NDIM(op[i]),
-                        ufunc->core_signature, num_dims);
-                return -1;
-            }
-
             /*
              * Make sure every core dimension exactly matches all other core
              * dimensions with the same label.
@@ -2162,6 +2149,24 @@ PyUFunc_GeneralizedFunction(PyUFuncObject *ufunc,
     }
 
     /*
+     * Check that operands have the minimum dimensions required.
+     * (Just checks core; broadcast dimensions are tested by the iterator.)
+     */
+    for (i = 0; i < nop; i++) {
+        if (op[i] != NULL && PyArray_NDIM(op[i]) < ufunc->core_num_dims[i]) {
+            PyErr_Format(PyExc_ValueError,
+                         "%s: %s operand %d does not have enough "
+                         "dimensions (has %d, gufunc core with "
+                         "signature %s requires %d)",
+                         ufunc_get_name_cstr(ufunc),
+                         i < nin ? "Input" : "Output",
+                         i < nin ? i : i - nin, PyArray_NDIM(op[i]),
+                         ufunc->core_signature, ufunc->core_num_dims[i]);
+            goto fail;
+        }
+    }
+
+    /*
      * Figure out the number of iteration dimensions, which
      * is the broadcast result of all the input non-core
      * dimensions.
@@ -2194,9 +2199,6 @@ PyUFunc_GeneralizedFunction(PyUFuncObject *ufunc,
 
     /* Possibly remap axes. */
     if (axes) {
-        /*
-         * possibly remap axes, using newly allocated memory.
-         */
         remap_axis = PyArray_malloc(sizeof(remap_axis[0]) * nop);
         remap_axis_memory = PyArray_malloc(sizeof(remap_axis_memory[0]) *
                                                   nop * NPY_MAXDIMS);
@@ -2212,7 +2214,7 @@ PyUFunc_GeneralizedFunction(PyUFuncObject *ufunc,
         if(retval < 0) {
             goto fail;
         }
-    } /* end of if(axis) */
+    }
 
     /* Collect the lengths of the labelled core dimensions */
     retval = _get_coredim_sizes(ufunc, op, core_dim_sizes, remap_axis);
diff --git a/numpy/core/tests/test_ufunc.py b/numpy/core/tests/test_ufunc.py
index 239e8bc64..7e1bfbdbe 100644
--- a/numpy/core/tests/test_ufunc.py
+++ b/numpy/core/tests/test_ufunc.py
@@ -689,6 +689,12 @@ class TestUfunc(object):
         assert_raises(TypeError, mm, a, b, axes=[(-2, -1), (-2, -1), None])
         # tuples should not have duplicated values
         assert_raises(ValueError, mm, a, b, axes=[(-2, -1), (-2, -1), (-2, -2)])
+        # arrays should have enough axes.
+        z = np.zeros((2, 2))
+        assert_raises(ValueError, mm, z, z[0])
+        assert_raises(ValueError, mm, z, z, out=z[:, 0])
+        assert_raises(ValueError, mm, z[1], z, axes=[0, 1])
+        assert_raises(ValueError, mm, z, z, out=z[0], axes=[0, 1])
 
     def test_innerwt(self):
         a = np.arange(6).reshape((2, 3))