move helper function to top of test class

Author: rcomer

cf_units/tests/test_unit.py

@@ -947,6 +947,25 @@ def test_decode_time(self):
 
 
 class Test_num2date:
+    def setup_units(self, calendar):
+        self.useconds = cf_units.Unit("seconds since 1970-01-01", calendar)
+        self.uminutes = cf_units.Unit("minutes since 1970-01-01", calendar)
+        self.uhours = cf_units.Unit("hours since 1970-01-01", calendar)
+        self.udays = cf_units.Unit("days since 1970-01-01", calendar)
+
+    def check_dates(self, nums, units, expected, only_cftime=True):
+        for num, unit, exp in zip(nums, units, expected):
+            res = unit.num2date(num, only_use_cftime_datetimes=only_cftime)
+            assert exp == res
+            assert isinstance(res, type(exp))
+
+    def check_timedelta(self, nums, units, expected):
+        for num, unit, exp in zip(nums, units, expected):
+            epoch = cftime.num2date(0, unit.cftime_unit, unit.calendar)
+            res = unit.num2date(num)
+            delta = res - epoch
+            assert (delta.days, delta.seconds, delta.microseconds) == exp
+
     def test_num2date(self):
         u = Unit(
             "hours since 2010-11-02 12:00:00",
@@ -980,25 +999,6 @@ def test_num2date_wrong_calendar(self):
                 only_use_python_datetimes=True,
             )
 
-    def setup_units(self, calendar):
-        self.useconds = cf_units.Unit("seconds since 1970-01-01", calendar)
-        self.uminutes = cf_units.Unit("minutes since 1970-01-01", calendar)
-        self.uhours = cf_units.Unit("hours since 1970-01-01", calendar)
-        self.udays = cf_units.Unit("days since 1970-01-01", calendar)
-
-    def check_dates(self, nums, units, expected, only_cftime=True):
-        for num, unit, exp in zip(nums, units, expected):
-            res = unit.num2date(num, only_use_cftime_datetimes=only_cftime)
-            assert exp == res
-            assert isinstance(res, type(exp))
-
-    def check_timedelta(self, nums, units, expected):
-        for num, unit, exp in zip(nums, units, expected):
-            epoch = cftime.num2date(0, unit.cftime_unit, unit.calendar)
-            res = unit.num2date(num)
-            delta = res - epoch
-            assert (delta.days, delta.seconds, delta.microseconds) == exp
-
     def test_scalar(self):
         unit = cf_units.Unit("seconds since 1970-01-01", "gregorian")
         num = 5.0