Added timezone test for ConciseDateFormatter

Author: ihincks

lib/matplotlib/tests/test_dates.py

@@ -511,6 +511,68 @@ def _create_auto_date_locator(date1, date2):
         assert strings == expected
 
 
+def test_concise_formatter_tz():
+    def _create_auto_date_locator(date1, date2, tz):
+        fig, ax = plt.subplots()
+
+        locator = mdates.AutoDateLocator(interval_multiples=True)
+        formatter = mdates.ConciseDateFormatter(locator, tz=tz)
+        ax.yaxis.set_major_locator(locator)
+        ax.yaxis.set_major_formatter(formatter)
+        ax.set_ylim(date1, date2)
+        fig.canvas.draw()
+        sts = []
+        for st in ax.get_yticklabels():
+            sts += [st.get_text()]
+        return sts, ax.yaxis.get_offset_text().get_text()
+
+    d1 = datetime.datetime(1997, 1, 1).replace(tzinfo=datetime.timezone.utc)
+    results = ([datetime.timedelta(weeks=52 * 200),
+                [str(t) for t in range(1980, 2201, 20)],
+                ""
+                ],
+               [datetime.timedelta(weeks=52),
+                ['1997', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug',
+                'Sep', 'Oct', 'Nov', 'Dec'],
+                "1997"
+                ],
+               [datetime.timedelta(days=141),
+                ['Jan', '22', 'Feb', '22', 'Mar', '22', 'Apr', '22',
+                 'May', '22'],
+                "1997-May"
+                ],
+               [datetime.timedelta(days=40),
+                ['Jan', '05', '09', '13', '17', '21', '25', '29', 'Feb',
+                 '05', '09'],
+                "1997-Feb"
+                ],
+               [datetime.timedelta(hours=40),
+                ['03:00', '07:00', '11:00', '15:00', '19:00', '23:00',
+                 '03:00', '07:00', '11:00', '15:00', '19:00'],
+                "1997-Jan-02"
+                ],
+               [datetime.timedelta(minutes=20),
+                ['03:00', '03:05', '03:10', '03:15', '03:20'],
+                "1997-Jan-01"
+                ],
+               [datetime.timedelta(seconds=40),
+                ['03:00', '05', '10', '15', '20', '25', '30', '35', '40'],
+                "1997-Jan-01 03:00"
+                ],
+               [datetime.timedelta(seconds=2),
+                ['59.5', '03:00', '00.5', '01.0', '01.5', '02.0', '02.5'],
+                "1997-Jan-01 03:00"
+                ],
+               )
+
+    new_tz = datetime.timezone(datetime.timedelta(hours=3))
+    for t_delta, expected_strings, expected_offset in results:
+        d2 = d1 + t_delta
+        strings, offset = _create_auto_date_locator(d1, d2, new_tz)
+        assert strings == expected_strings
+        assert offset == expected_offset
+
+
 def test_auto_date_locator_intmult_tz():
     def _create_auto_date_locator(date1, date2, tz):
         locator = mdates.AutoDateLocator(interval_multiples=True, tz=tz)