add is_business_day method to date

pendulum/date.py

@@ -26,7 +26,6 @@
 
 
 class Date(FormattableMixin, date):
-
     # Names of days of the week
     _days = {
         SUNDAY: "Sunday",
@@ -217,6 +216,33 @@ def is_anniversary(self, dt=None):
     # the old name can be completely replaced with the new in one of the future versions
     is_birthday = is_anniversary
 
+    def is_business_day(self, holidays: [list, tuple] = None) -> bool:
+        """
+        Check if the date is a business day (not a weekend), including checking against an optional list of holidays
+
+        :param holidays: list or tuple containing Date or DateTime objects to be considered holidays
+        :type holidays: list, tuple
+
+        :rtype: bool
+            True if the date is a business day, otherwise false
+        """
+
+        # check if this date is a weekend
+        if self.day_of_week == SATURDAY \
+                or self.day_of_week == SUNDAY:
+            return False
+
+        # check if this date falls on a holiday
+        if holidays is not None:
+            # TODO: prefilter the holiday list by year (test for speed)
+            for holiday in holidays:
+                if self.is_same_day(holiday):
+                    return False
+
+            return False
+
+        return True
+
     # ADDITIONS AND SUBSTRACTIONS
 
     def add(self, years=0, months=0, weeks=0, days=0):

tests/date/test_comparison.py

@@ -243,3 +243,14 @@ def test_comparison_to_unsupported():
 
     assert not dt1 == "test"
     assert dt1 not in ["test"]
+
+
+def test_is_business_day():
+    dt1 = pendulum.Date(2021, 11, 13)  # weekend
+    dt2 = pendulum.Date(2021, 11, 15)  # not weekend
+
+    holidays = [pendulum.Date(2020, 11, 15)]
+
+    assert not dt1.is_business_day()
+    assert dt2.is_business_day()
+    assert not dt2.is_business_day(holidays=holidays)