TST: Add more scalar tests to ensure `inner` keeps the answer with the right form.

1 files changed, 16 insertions, 0 deletions

diff --git a/numpy/core/tests/test_multiarray.py b/numpy/core/tests/test_multiarray.py
index 6fa4b6bbb..7bb267cfb 100644
--- a/numpy/core/tests/test_multiarray.py
+++ b/numpy/core/tests/test_multiarray.py
@@ -4825,6 +4825,22 @@ if sys.version_info[:2] >= (3, 5):
 
 class TestInner(TestCase):
 
+    def test_inner_scalar_and_vector(self):
+        for dt in np.typecodes['AllInteger'] + np.typecodes['AllFloat'] + '?':
+            sca = np.array(3, dtype=dt)[()]
+            vec = np.array([1, 2], dtype=dt)
+            desired = np.array([3, 6], dtype=dt)
+            assert_equal(np.inner(vec, sca), desired)
+            assert_equal(np.inner(sca, vec), desired)
+
+    def test_inner_scalar_and_matrix(self):
+        for dt in np.typecodes['AllInteger'] + np.typecodes['AllFloat'] + '?':
+            sca = np.array(3, dtype=dt)[()]
+            arr = np.matrix([[1, 2], [3, 4]], dtype=dt)
+            desired = np.matrix([[3, 6], [9, 12]], dtype=dt)
+            assert_equal(np.inner(arr, sca), desired)
+            assert_equal(np.inner(sca, arr), desired)
+
     def test_inner_scalar_and_matrix_of_objects(self):
         # Ticket #4482
         arr = np.matrix([1, 2], dtype=object)