Add to unit testing examples

Author: gerhynes

README.md

@@ -2411,3 +2411,25 @@ To see comments, run
 ```
 python3 name_of_test_file.py -v
 ```
+
+### Common Assertions
+
+- `self.assertEqual(x,y)`
+- `self.assertNotEqual(x,y)`
+- `self.assertTrue(x)`
+- `self.assertFalse(x)`
+- `self.assertIsNone(x)`
+- `self.assertIsNotNone(x)`
+
+### Testing for errors
+
+When testing for errors, `self.assertRaises` lets you test for a specific type of error.
+
+```python
+class SomeTests(unittest.TestCase):
+    def testing_for_errors(self):
+        """testing for an error"""
+        with self.assertRaises(IndexError):
+            l = [1,2,3]
+            l[100]
+```

unit_testing/activities.py

@@ -1,4 +1,8 @@
+from random import choice
+
 def eat(food, is_healthy):
+    if not isinstance(is_healthy, bool):
+        raise ValueError("is_healthy must be a boolean")
     ending = "because YOLO"
     if is_healthy:
         ending = "because my body is a temple"
@@ -7,4 +11,11 @@ def eat(food, is_healthy):
 def nap(num_hours):
     if num_hours >= 2:
         return f"Ugh, I overslept. I didn't mean to nap for {num_hours} hours"
-    return f"I'm feeling refreshed after my {num_hours} hour nap"
+    return f"I'm feeling refreshed after my {num_hours} hour nap"
+
+def is_funny(person):
+    if person is "tim": return False
+    return True
+
+def laugh():
+    return choice(("lol", "haha", "tehehe"))

unit_testing/tests.py

@@ -1,5 +1,5 @@
 import unittest
-from activities import eat, nap
+from activities import eat, nap, is_funny, laugh
 
 class ActivityTest(unittest.TestCase):
     def test_eat_healthy(self):
@@ -8,24 +8,45 @@ def test_eat_healthy(self):
             eat("broccoli", is_healthy=True),
             "I'm eating broccoli, because my body is a temple"
         )
+
     def test_eat_unhealthy(self):
         """eat should indicate you've given up for unhealthy eating"""
         self.assertEqual(
             eat("pizza", is_healthy=False),
             "I'm eating pizza, because YOLO"
         )
+
+    def test_eat_healthy_boolean(self):
+        """is_healthy must be a boolean"""
+        with self.assertRaises(ValueError):
+            eat("pizza", is_healthy="who cares?")
+
     def test_short_nap(self):
         """short naps should be refreshing"""
         self.assertEqual(
             nap(1),
             "I'm feeling refreshed after my 1 hour nap"
         )
+
     def test_long_nap(self):
         """long naps should be discouraging"""
         self.assertEqual(
             nap(3),
             "Ugh, I overslept. I didn't mean to nap for 3 hours"
         )
 
+    def test_is_funny_tim(self):
+        """Tim should not be funny"""
+        self.assertFalse(is_funny("tim"), "Tim should not be funny")
+
+    def test_is_funny_anyone_else(self):
+        """anyone else but Tim should be funny"""
+        self.assertTrue(is_funny("blue"), "Blue should be funny")
+        self.assertTrue(is_funny("tammy"), "Tammy should be funny")
+        self.assertTrue(is_funny("sven"), "Sven should be funny")
+
+    def test_laugh(self):
+        self.assertIn(laugh(), ("lol", "haha", "tehehe"))
+
 if __name__ == "__main__":
     unittest.main()