bpo-35078: Allow customization of CSS class name of a month in calendar module (gh-10137)

Refactor formatweekday(), formatmonthname() methods in LocaleHTMLCalendar and LocaleTextCalendar classes in calendar module to call the base class methods. This enables customizable CSS classes for LocaleHTMLCalendar and LocaleTextCalendar.

Patch by Srinivas Reddy Thatiparthy

Lib/calendar.py

@@ -571,19 +571,11 @@ class LocaleTextCalendar(TextCalendar):
 
     def formatweekday(self, day, width):
         with different_locale(self.locale):
-            if width >= 9:
-                names = day_name
-            else:
-                names = day_abbr
-            name = names[day]
-            return name[:width].center(width)
+            return super().formatweekday(day, width)
 
     def formatmonthname(self, theyear, themonth, width, withyear=True):
         with different_locale(self.locale):
-            s = month_name[themonth]
-            if withyear:
-                s = "%s %r" % (s, theyear)
-            return s.center(width)
+            return super().formatmonthname(theyear, themonth, width, withyear)
 
 
 class LocaleHTMLCalendar(HTMLCalendar):
@@ -601,16 +593,11 @@ class LocaleHTMLCalendar(HTMLCalendar):
 
     def formatweekday(self, day):
         with different_locale(self.locale):
-            s = day_abbr[day]
-            return '<th class="%s">%s</th>' % (self.cssclasses[day], s)
+            return super().formatweekday(day)
 
     def formatmonthname(self, theyear, themonth, withyear=True):
         with different_locale(self.locale):
-            s = month_name[themonth]
-            if withyear:
-                s = '%s %s' % (s, theyear)
-            return '<tr><th colspan="7" class="month">%s</th></tr>' % s
-
+            return super().formatmonthname(theyear, themonth, withyear)
 
 # Support for old module level interface
 c = TextCalendar()

Lib/test/test_calendar.py

@@ -564,6 +564,30 @@ class CalendarTestCase(unittest.TestCase):
         new_october = calendar.TextCalendar().formatmonthname(2010, 10, 10)
         self.assertEqual(old_october, new_october)
 
+    def test_locale_html_calendar_custom_css_class_month_name(self):
+        try:
+            cal = calendar.LocaleHTMLCalendar(locale='')
+            local_month = cal.formatmonthname(2010, 10, 10)
+        except locale.Error:
+            # cannot set the system default locale -- skip rest of test
+            raise unittest.SkipTest('cannot set the system default locale')
+        self.assertIn('class="month"', local_month)
+        cal.cssclass_month_head = "text-center month"
+        local_month = cal.formatmonthname(2010, 10, 10)
+        self.assertIn('class="text-center month"', local_month)
+
+    def test_locale_html_calendar_custom_css_class_weekday(self):
+        try:
+            cal = calendar.LocaleHTMLCalendar(locale='')
+            local_weekday = cal.formatweekday(6)
+        except locale.Error:
+            # cannot set the system default locale -- skip rest of test
+            raise unittest.SkipTest('cannot set the system default locale')
+        self.assertIn('class="sun"', local_weekday)
+        cal.cssclasses_weekday_head = ["mon2", "tue2", "wed2", "thu2", "fri2", "sat2", "sun2"]
+        local_weekday = cal.formatweekday(6)
+        self.assertIn('class="sun2"', local_weekday)
+
     def test_itermonthdays3(self):
         # ensure itermonthdays3 doesn't overflow after datetime.MAXYEAR
         list(calendar.Calendar().itermonthdays3(datetime.MAXYEAR, 12))

Misc/NEWS.d/next/Library/2018-10-27-09-37-03.bpo-35078.kweA3R.rst

@@ -0,0 +1,3 @@
+Refactor formatweekday, formatmonthname methods in LocaleHTMLCalendar and LocaleTextCalendar classes in calendar module to call the base class methods.This enables customizable CSS classes for LocaleHTMLCalendar.
+Patch by Srinivas Reddy Thatiparthy
+