Update the docstring and add test

Author: antonwolfy

dpnp/dpnp_iface_manipulation.py

@@ -2504,14 +2504,17 @@ def pad(array, pad_width, mode="constant", **kwargs):
     ----------
     array : {dpnp.ndarray, usm_ndarray}
         The array of rank ``N`` to pad.
-    pad_width : {sequence, array_like, int}
+    pad_width : {sequence, array_like, int, dict}
         Number of values padded to the edges of each axis.
         ``((before_1, after_1), ... (before_N, after_N))`` unique pad widths
         for each axis.
         ``(before, after)`` or ``((before, after),)`` yields same before
         and after pad for each axis.
         ``(pad,)`` or ``int`` is a shortcut for ``before = after = pad`` width
         for all axes.
+        If a dictionary, each key is an axis and its corresponding value is an
+        integer or a pair of integers describing the padding ``(before, after)``
+        or ``pad`` width for that axis.
     mode : {str, function}, optional
         One of the following string values or a user supplied function.
 
@@ -2694,6 +2697,26 @@ def pad(array, pad_width, mode="constant", **kwargs):
            [100, 100, 100, 100, 100, 100, 100],
            [100, 100, 100, 100, 100, 100, 100]])
 
+    >>> a = np.arange(1, 7).reshape(2, 3)
+    >>> np.pad(a, {1: (1, 2)})
+    array([[0, 1, 2, 3, 0, 0],
+           [0, 4, 5, 6, 0, 0]])
+    >>> np.pad(a, {-1: 2})
+    array([[0, 0, 1, 2, 3, 0, 0],
+           [0, 0, 4, 5, 6, 0, 0]])
+    >>> np.pad(a, {0: (3, 0)})
+    array([[0, 0, 0],
+           [0, 0, 0],
+           [0, 0, 0],
+           [1, 2, 3],
+           [4, 5, 6]])
+    >>> np.pad(a, {0: (3, 0), 1: 2})
+    array([[0, 0, 0, 0, 0, 0, 0],
+           [0, 0, 0, 0, 0, 0, 0],
+           [0, 0, 0, 0, 0, 0, 0],
+           [0, 0, 1, 2, 3, 0, 0],
+           [0, 0, 4, 5, 6, 0, 0]])
+
     """
 
     dpnp.check_supported_arrays_type(array)

dpnp/tests/test_arraypad.py

@@ -539,3 +539,21 @@ def test_as_pairs_exceptions(self):
             dpnp_as_pairs([[1, 2], [3, 4]], 3)
         with pytest.raises(ValueError, match="could not be broadcast"):
             dpnp_as_pairs(dpnp.ones((2, 3)), 3)
+
+    @testing.with_requires("numpy>=2.4")
+    @pytest.mark.parametrize(
+        "sh, pad_width",
+        [
+            ((3, 4, 5), {-2: (1, 3)}),
+            ((3, 4, 5), {0: (5, 2)}),
+            ((3, 4, 5), {0: (5, 2), -1: (3, 4)}),
+            ((3, 4, 5), {1: 5}),
+        ],
+    )
+    def test_dict_pad_width(self, sh, pad_width):
+        a = numpy.zeros(sh)
+        ia = dpnp.array(a)
+
+        result = dpnp.pad(ia, pad_width)
+        expected = numpy.pad(a, pad_width)
+        assert_equal(result, expected)