bpo-36782: Created C API wrappers and added missing tests for functions in the PyDateTimeAPI. (#13088)

* created a c API wrapper for pyDate_FromDate and added the test

* 📜🤖 Added by blurb_it.

* fixed auto-alignment by vscode

* made changes as per PEP7

* Update 2019-05-04-21-25-19.bpo-36782.h3oPIb.rst

* Refactored code as per requested changes

* Remove Whitespace to Fix failed travis build

* Update 2019-05-04-21-25-19.bpo-36782.h3oPIb.rst

* Add a new line at end of ACKS

* Added C API function for PyDateTime_FromDateAndTime

* Added a test for the C API wrapper of PyDateTime_FromDateAndTime

* Added C API function for PyDateTime_FromDateAndTime

* Added a test for the C API wrapper of PyDateTime_FromDateAndTimeAndFold

* Remove Whitespace using patchcheck

* Added a C API function for PyTime_FromTime

* Added a test for the C API wrapper of PyTime_FromTime

* Added a C API function for PyTime_FromTimeAndFold

* Added a test for the C API wrapper of PyTime_FromTimeAndFold

* Added a C API function for PyDelta_FromDSU

* Added a test for the C API wrapper of PyDelta_FromDSU

* Refactor code, re-edit lines longer than 80 chars

* Fix Whitespace issues in DatetimeTester

* List all tests that were added in this PR

* Update 2019-05-04-21-25-19.bpo-36782.h3oPIb.rst

* Reformat code as per PEP7 guidelines

* Remove unused varibles from another function

* Added specific tests for the Fold Attribute

* Update 2019-05-04-21-25-19.bpo-36782.h3oPIb.rst

* Reformat code according to requested changes

* Reformat code to PEP7 Guidelines

* Reformat code to PEP7 Guidelines

* Re-add name to blurb

* Added a backtick to blurb file

* Update 2019-05-04-21-25-19.bpo-36782.h3oPIb.rst

* Remove the need to initialize mandatory parameters

* Make the macro parameter mandatory

* Re-arrange the order of unit-test args

* Removed the need to initialize macro

change all the int macro = 0 to int macro; now that macro is required

Co-Authored-By: Paul Ganssle <pganssle@users.noreply.github.com>

* Removed the need to initialize macro

change all the `int macro = 0` to `int macro`; now that macro is required

Co-Authored-By: Paul Ganssle <pganssle@users.noreply.github.com>

* Removed the need to initialize macro

change all the `int macro = 0` to `int macro`; now that macro is required

Co-Authored-By: Paul Ganssle <pganssle@users.noreply.github.com>

* Removed the need to initialize macro

change all the `int macro = 0` to `int macro`; now that macro is required

Co-Authored-By: Paul Ganssle <pganssle@users.noreply.github.com>

* Removed the need to initialize macro

change all the `int macro = 0` to `int macro`; now that macro is required

Co-Authored-By: Paul Ganssle <pganssle@users.noreply.github.com>

* Removed the need to initialize macro

change all the `int macro = 0` to `int macro`; now that macro is required

Co-Authored-By: Paul Ganssle <pganssle@users.noreply.github.com>
diff --git a/Lib/test/datetimetester.py b/Lib/test/datetimetester.py
index af0047f..239a0b5 100644
--- a/Lib/test/datetimetester.py
+++ b/Lib/test/datetimetester.py
@@ -6018,6 +6018,100 @@
                 with self.subTest(arg=arg, exact=exact):
                     self.assertFalse(is_tzinfo(arg, exact))
 
+    def test_date_from_date(self):
+        exp_date = date(1993, 8, 26)
+
+        for macro in [0, 1]:
+            with self.subTest(macro=macro):
+                c_api_date = _testcapi.get_date_fromdate(
+                    macro,
+                    exp_date.year,
+                    exp_date.month,
+                    exp_date.day)
+
+                self.assertEqual(c_api_date, exp_date)
+
+    def test_datetime_from_dateandtime(self):
+        exp_date = datetime(1993, 8, 26, 22, 12, 55, 99999)
+
+        for macro in [0, 1]:
+            with self.subTest(macro=macro):
+                c_api_date = _testcapi.get_datetime_fromdateandtime(
+                    macro,
+                    exp_date.year,
+                    exp_date.month,
+                    exp_date.day,
+                    exp_date.hour,
+                    exp_date.minute,
+                    exp_date.second,
+                    exp_date.microsecond)
+
+                self.assertEqual(c_api_date, exp_date)
+
+    def test_datetime_from_dateandtimeandfold(self):
+        exp_date = datetime(1993, 8, 26, 22, 12, 55, 99999)
+
+        for fold in [0, 1]:
+            for macro in [0, 1]:
+                with self.subTest(macro=macro, fold=fold):
+                    c_api_date = _testcapi.get_datetime_fromdateandtimeandfold(
+                        macro,
+                        exp_date.year,
+                        exp_date.month,
+                        exp_date.day,
+                        exp_date.hour,
+                        exp_date.minute,
+                        exp_date.second,
+                        exp_date.microsecond,
+                        exp_date.fold)
+
+                    self.assertEqual(c_api_date, exp_date)
+                    self.assertEqual(c_api_date.fold, exp_date.fold)
+
+    def test_time_from_time(self):
+        exp_time = time(22, 12, 55, 99999)
+
+        for macro in [0, 1]:
+            with self.subTest(macro=macro):
+                c_api_time = _testcapi.get_time_fromtime(
+                    macro,
+                    exp_time.hour,
+                    exp_time.minute,
+                    exp_time.second,
+                    exp_time.microsecond)
+
+                self.assertEqual(c_api_time, exp_time)
+
+    def test_time_from_timeandfold(self):
+        exp_time = time(22, 12, 55, 99999)
+
+        for fold in [0, 1]:
+            for macro in [0, 1]:
+                with self.subTest(macro=macro, fold=fold):
+                    c_api_time = _testcapi.get_time_fromtimeandfold(
+                        macro,
+                        exp_time.hour,
+                        exp_time.minute,
+                        exp_time.second,
+                        exp_time.microsecond,
+                        exp_time.fold)
+
+                    self.assertEqual(c_api_time, exp_time)
+                    self.assertEqual(c_api_time.fold, exp_time.fold)
+
+    def test_delta_from_dsu(self):
+        exp_delta = timedelta(26, 55, 99999)
+
+        for macro in [0, 1]:
+            with self.subTest(macro=macro):
+                c_api_delta = _testcapi.get_delta_fromdsu(
+                    macro,
+                    exp_delta.days,
+                    exp_delta.seconds,
+                    exp_delta.microseconds)
+
+                self.assertEqual(c_api_delta, exp_delta)
+
     def test_date_from_timestamp(self):
         ts = datetime(1995, 4, 12).timestamp()
 
@@ -6028,9 +6122,6 @@
                 self.assertEqual(d, date(1995, 4, 12))
 
     def test_datetime_from_timestamp(self):
-        ts0 = datetime(1995, 4, 12).timestamp()
-        ts1 = datetime(1995, 4, 12, 12, 30).timestamp()
-
         cases = [
             ((1995, 4, 12), None, False),
             ((1995, 4, 12), None, True),