Increase coverage (matplotlib#26346)

* add test for strip_math

* add test for strip_math

Author: eendebakpt

lib/matplotlib/tests/test_cbook.py

@@ -15,7 +15,7 @@
 
 from matplotlib import _api, cbook
 import matplotlib.colors as mcolors
-from matplotlib.cbook import delete_masked_points
+from matplotlib.cbook import delete_masked_points, strip_math
 
 
 class Test_delete_masked_points:
@@ -918,6 +918,12 @@ def test_safe_first_element_with_none():
     assert actual is not None and actual == datetime_lst[1]
 
 
+def test_strip_math():
+    assert strip_math(r'1 \times 2') == r'1 \times 2'
+    assert strip_math(r'$1 \times 2$') == '1 x 2'
+    assert strip_math(r'$\rm{hi}$') == 'hi'
+
+
 @pytest.mark.parametrize('fmt, value, result', [
     ('%.2f m', 0.2, '0.20 m'),
     ('{:.2f} m', 0.2, '0.20 m'),