removing unittest, using assert

ipynb/pres031_functions_testing.ipynb

@@ -14,12 +14,10 @@
 
 ## Why testing (1/4) ? 
 
 Coding without testing is dangerous (anyway, you will test somehow): 
 
-https://lesjoiesducode.fr/quand-le-client-veut-une-mise-en-prod-avant-de-boucler-ses-tests
-
 https://lesjoiesducode.fr/quand-je-dploie-en-prod-sans-tester
 
 
 
 %% Cell type:markdown id: tags:
@@ -28,22 +26,22 @@
 
 Your get more confident with your code: 
 
 https://lesjoiesducode.fr/quand-jai-blinde-mes-tests-et-que-les-recetteurs-commencent-a-passer-sur-mes-devs
 
-https://thecodinglove.com/when-i-run-my-code-for-the-first-time-and-i-didnt-test-anything
 
 
 %% Cell type:markdown id: tags:
 
 ## Why testing (3/4) ? 
 
-To get sure I conform with the specs, and/or define correct specs: 
+To get sure I conform with the specs, and/or define correct specs. 
+Important when something went wrong ... 
 
 https://thecodinglove.com/solid-code-wrong-specs
 
-ease parallel dev. and code integration.
+Ease parallel dev. and code integration.
 
 %% Cell type:markdown id: tags:
 
 ## Why testing (4/4) ?
 
@@ -159,37 +157,70 @@
 
 ### How to test ? 
 
 Different possibilities 
 
+- just use assert ! 
+
+Not detailed here:
+
 - use unittest from the standard lib 
 
 - use pytest (rather standard, but need to be installed)
 
 - ....
 
+%% Cell type:markdown id: tags:
+
+### Assert ? 
+
+assert test a condition and "crashes" if the condition does not evaluate to True
+
+%% Cell type:code id: tags:
+
+``` python
+assert 13 == 10+3
+assert type(10) is int
+```
+
+%% Cell type:code id: tags:
+
+``` python
+assert True is False
+```
+
+%%%% Output: error
+
+    ---------------------------------------------------------------------------
+    AssertionError                            Traceback (most recent call last)
+    <ipython-input-10-bf474889e709> in <module>
+    ----> 1 assert True is False
+
+    AssertionError:
+
 %% Cell type:code id: tags:
 
 ``` python
-import unittest 
 
 def add(arg0, arg1):
     """Print and return the sum of the two arguments (duck typing).
     assuming arg0 + arg1 is well defined. 
     """
     result = arg0 + arg1
     return result
 
+def test_add():
+    """ test add is ok with int and strings"""
+    print("testing add with int ", end="")
+    assert add(1, 2) == 3
+    print(" .... OK")
+    print("testing add ok with str", end="")
+    assert add("a", "b") == "ab"
+    print("... OK")
+    print("test add ok")
 
-class TestMyStuff(unittest.TestCase):    
-    def test_add(self):
-        """ test add """
-        self.assertEqual(8, add(3, 5))
-        self.assertEqual("aabb", add("aa", "bb"))
-        # self.assertEqual(None, add(None, None))
-
-_res = unittest.TextTestRunner(verbosity=2).run(unittest.TestLoader().loadTestsFromTestCase(TestMyStuff))
+test_add()
 ```
 
 %% Cell type:code id: tags:
 
 ``` python
@@ -217,11 +248,10 @@
 Write a function that returns the sum of the first argument with twice the second argument.
 
 %% Cell type:code id: tags:
 
 ``` python
-import unittest
 
 def add_second_twice(arg0, arg1):
     """Return the sum of the first argument with twice the second one.
         Arguments should be of type that support sum and product by 
         an integer (e.g. numerical, string, list, ...)
@@ -230,20 +260,43 @@
         :return: arg0 + 2 * arg1
     """
     pass
 
 
-class TestMyStuff0(unittest.TestCase):    
-    def test_add_second_twice(self):
-        """ test add_second_twice"""
-        self.assertEqual(13, add_second_twice(3, 5))
-        self.assertEqual("aabbbb", add_second_twice("aa", "bb"))
-        self.assertListEqual([1, 2, 3, 4, 3, 4], add_second_twice([1, 2], [3, 4])) 
-        
-_res = unittest.TextTestRunner(verbosity=2).run(unittest.TestLoader().loadTestsFromTestCase(TestMyStuff0))
+def test_add_second_twice():
+    """ test add second twice"""
+    print("testing add second twice with int ", end="")
+    assert add_second_twice(3, 5) == 13
+    print("...OK")
+    print("testing add second twice with strings ", end="")
+    assert add_second_twice("aa", "bb") == "aabbbb"
+    print("...OK")
+    print("testing add second twice with list ", end="")
+    assert add_second_twice([1,2], [3,4]) == [1, 2, 3, 4, 3, 4]
+    print("...OK")
+    print("test add second twice OK with int, string and list")
+
+test_add_second_twice()
 ```
 
+%%%% Output: error
+
+    ---------------------------------------------------------------------------
+    AssertionError                            Traceback (most recent call last)
+    <ipython-input-5-84287d31dec0> in <module>
+         25     print("test add second twice OK with int, string and list")
+         26
+    ---> 27 test_add_second_twice()
+
+    <ipython-input-5-84287d31dec0> in test_add_second_twice()
+         15     """ test add second twice"""
+         16     print("testing add second twice with int ", end="")
+    ---> 17     assert add_second_twice(3, 5) == 13
+         18     print("...OK")
+         19     print("testing add second twice with strings ", end="")
+    AssertionError:
+
 %% Cell type:markdown id: tags:
 
 ### Do it yourself: simple function definition
 
 **A solution:**
@@ -263,20 +316,24 @@
     """
     result = arg0 + 2*arg1
     print(f'arg0 + 2*arg1 = {arg0} + 2*{arg1} = {result}')
     return result
 
+def test_add_second_twice():
+    """ test add second twice"""
+    print("testing add second twice with int ", end="")
+    assert add_second_twice(3, 5) == 13
+    print("...OK")
+    print("testing add second twice with strings ", end="")
+    assert add_second_twice("aa", "bb") == "aabbbb"
+    print("...OK")
+    print("testing add second twice with list ", end="")
+    assert add_second_twice([1,2], [3,4]) == [1, 2, 3, 4, 3, 4]
+    print("...OK")
+    print("test add second twice OK with int, string and list")
 
-class TestMyStuff0(unittest.TestCase):    
-    def test_add_second_twice(self):
-        """ test add_second_twice"""
-        self.assertEqual(13, add_second_twice(3, 5))
-        self.assertEqual("aabbbb", add_second_twice("aa", "bb"))
-        self.assertListEqual([1, 2, 3, 4, 3, 4], add_second_twice([1, 2], [3, 4])) 
-        
-_res = unittest.TextTestRunner(verbosity=2).run(unittest.TestLoader().loadTestsFromTestCase(TestMyStuff0))
-
+test_add_second_twice()
 ```
 
 %% Cell type:code id: tags:
 
 ``` python