MAINT: Apply ruff/flake8-comprehensions rule C417

C417 Unnecessary `map` usage (rewrite using a generator expression)

Author: DimitriPapadopoulos

numpy/_core/tests/test_multiarray.py

@@ -5478,7 +5478,7 @@ def test_roundtrip_str(self, x):
 
     def test_roundtrip_repr(self, x):
         x = x.real.ravel()
-        s = "@".join(map(lambda x: repr(x)[11:-1], x))
+        s = "@".join((repr(x)[11:-1] for x in x))
         y = np.fromstring(s, sep="@")
         assert_array_equal(x, y)
 

numpy/_core/tests/test_shape_base.py

@@ -156,7 +156,7 @@ def test_generator(self):
         with pytest.raises(TypeError, match="arrays to stack must be"):
             hstack(np.arange(3) for _ in range(2))
         with pytest.raises(TypeError, match="arrays to stack must be"):
-            hstack(map(lambda x: x, np.ones((3, 2))))
+            hstack((x for x in np.ones((3, 2))))
 
     def test_casting_and_dtype(self):
         a = np.array([1, 2, 3])