Merge pull request matplotlib#19849 from smartlixx/FIX_date_usetex

FIX: DateFormatter for month names when usetex=True

Author: tacaswell

lib/matplotlib/dates.py

@@ -172,6 +172,7 @@
 import functools
 import logging
 import math
+import re
 
 from dateutil.rrule import (rrule, MO, TU, WE, TH, FR, SA, SU, YEARLY,
                             MONTHLY, WEEKLY, DAILY, HOURLY, MINUTELY,
@@ -591,8 +592,13 @@ def drange(dstart, dend, delta):
 
 
 def _wrap_in_tex(text):
+    p = r'([a-zA-Z]+)'
+    ret_text = re.sub(p, r'}$\1$\\mathdefault{', text)
+
     # Braces ensure dashes are not spaced like binary operators.
-    return '$\\mathdefault{' + text.replace('-', '{-}') + '}$'
+    ret_text = '$\\mathdefault{'+ret_text.replace('-', '{-}')+'}$'
+    ret_text = ret_text.replace('$\\mathdefault{}$', '')
+    return ret_text
 
 
 ## date tickers and formatters ###

lib/matplotlib/tests/test_dates.py

@@ -271,7 +271,7 @@ def callable_formatting_function(dates, _):
     (datetime.timedelta(weeks=52 * 200),
      [r'$\mathdefault{%d}$' % (year,) for year in range(1990, 2171, 20)]),
     (datetime.timedelta(days=30),
-     [r'$\mathdefault{Jan %02d 1990}$' % (day,) for day in range(1, 32, 3)]),
+     [r'Jan$\mathdefault{ %02d 1990}$' % (day,) for day in range(1, 32, 3)]),
     (datetime.timedelta(hours=20),
      [r'$\mathdefault{%02d:00:00}$' % (hour,) for hour in range(0, 21, 2)]),
 ])
@@ -550,15 +550,15 @@ def test_concise_formatter_show_offset(t_delta, expected):
     (datetime.timedelta(weeks=52 * 200),
      ['$\\mathdefault{%d}$' % (t, ) for t in range(1980, 2201, 20)]),
     (datetime.timedelta(days=40),
-     ['$\\mathdefault{Jan}$', '$\\mathdefault{05}$', '$\\mathdefault{09}$',
+     ['Jan', '$\\mathdefault{05}$', '$\\mathdefault{09}$',
       '$\\mathdefault{13}$', '$\\mathdefault{17}$', '$\\mathdefault{21}$',
-      '$\\mathdefault{25}$', '$\\mathdefault{29}$', '$\\mathdefault{Feb}$',
+      '$\\mathdefault{25}$', '$\\mathdefault{29}$', 'Feb',
       '$\\mathdefault{05}$', '$\\mathdefault{09}$']),
     (datetime.timedelta(hours=40),
-     ['$\\mathdefault{Jan{-}01}$', '$\\mathdefault{04:00}$',
+     ['Jan$\\mathdefault{{-}01}$', '$\\mathdefault{04:00}$',
       '$\\mathdefault{08:00}$', '$\\mathdefault{12:00}$',
       '$\\mathdefault{16:00}$', '$\\mathdefault{20:00}$',
-      '$\\mathdefault{Jan{-}02}$', '$\\mathdefault{04:00}$',
+      'Jan$\\mathdefault{{-}02}$', '$\\mathdefault{04:00}$',
       '$\\mathdefault{08:00}$', '$\\mathdefault{12:00}$',
       '$\\mathdefault{16:00}$']),
     (datetime.timedelta(seconds=2),