Add test_axvline to test_datetime.py

Author: CozyFrog

lib/matplotlib/tests/test_datetime.py

@@ -44,11 +44,19 @@ def test_axline(self):
         fig, ax = plt.subplots()
         ax.axline(...)
 
-    @pytest.mark.xfail(reason="Test for axvline not written yet")
     @mpl.style.context("default")
     def test_axvline(self):
-        fig, ax = plt.subplots()
-        ax.axvline(...)
+        mpl.rcParams["date.converter"] = 'concise'
+        fig, (ax1, ax2, ax3) = plt.subplots(3, 1, layout='constrained')
+        ax1.set_xlim(left=datetime.datetime(2020, 4, 1),
+                     right=datetime.datetime(2020, 8, 1))
+        ax2.set_xlim(left=np.datetime64('2005-01-01'),
+                     right=np.datetime64('2005-04-01'))
+        ax3.set_xlim(left=datetime.datetime(2023, 9, 1),
+                     right=datetime.datetime(2023, 11, 1))
+        ax1.axvline(x=datetime.datetime(2020, 6, 3), ymin=0.5, ymax=0.7)
+        ax2.axvline(np.datetime64('2005-02-25T03:30'), ymin=0.1, ymax=0.9)
+        ax3.axvline(x=datetime.datetime(2023, 10, 24), ymin=0.4, ymax=0.7)
 
     @pytest.mark.xfail(reason="Test for axvspan not written yet")
     @mpl.style.context("default")