5.2.1 Organizing test code

The basic building blocks of unit testing are test cases -- single scenarios that must be set up and checked for correctness. In PyUnit, test cases are represented by instances of the TestCase class in the unittest module. To make your own test cases you must write subclasses of TestCase, or use FunctionTestCase.

An instance of a TestCase-derived class is an object that can completely run a single test method, together with optional set-up and tidy-up code.

The testing code of a TestCase instance should be entirely self contained, such that it can be run either in isolation or in arbitrary combination with any number of other test cases.

The simplest test case subclass will simply override the runTest() method in order to perform specific testing code:

import unittest

class DefaultWidgetSizeTestCase(unittest.TestCase):
    def runTest(self):
        widget = Widget("The widget")
        self.failUnless(widget.size() == (50,50), 'incorrect default size')

Note that in order to test something, we use the one of the assert*() or fail*() methods provided by the TestCase base class. If the test fails when the test case runs, an exception will be raised, and the testing framework will identify the test case as a failure. Other exceptions that do not arise from checks made through the assert*() and fail*() methods are identified by the testing framework as dfnerrors.

The way to run a test case will be described later. For now, note that to construct an instance of such a test case, we call its constructor without arguments:

testCase = DefaultWidgetSizeTestCase()

Now, such test cases can be numerous, and their set-up can be repetitive. In the above case, constructing a ``Widget'' in each of 100 Widget test case subclasses would mean unsightly duplication.

Luckily, we can factor out such set-up code by implementing a method called setUp(), which the testing framework will automatically call for us when we run the test:

import unittest

class SimpleWidgetTestCase(unittest.TestCase):
    def setUp(self):
        self.widget = Widget("The widget")

class DefaultWidgetSizeTestCase(SimpleWidgetTestCase):
    def runTest(self):
        self.failUnless(self.widget.size() == (50,50),
                        'incorrect default size')

class WidgetResizeTestCase(SimpleWidgetTestCase):
    def runTest(self):
        self.widget.resize(100,150)
        self.failUnless(self.widget.size() == (100,150),
                        'wrong size after resize')

If the setUp() method raises an exception while the test is running, the framework will consider the test to have suffered an error, and the runTest() method will not be executed.

Similarly, we can provide a tearDown() method that tidies up after the runTest() method has been run:

import unittest

class SimpleWidgetTestCase(unittest.TestCase):
    def setUp(self):
        self.widget = Widget("The widget")

    def tearDown(self):
        self.widget.dispose()
        self.widget = None

If setUp() succeeded, the tearDown() method will be run regardless of whether or not runTest() succeeded.

Such a working environment for the testing code is called a fixture.

Often, many small test cases will use the same fixture. In this case, we would end up subclassing SimpleWidgetTestCase into many small one-method classes such as DefaultWidgetSizeTestCase. This is time-consuming and discouraging, so in the same vein as JUnit, PyUnit provides a simpler mechanism:

import unittest

class WidgetTestCase(unittest.TestCase):
    def setUp(self):
        self.widget = Widget("The widget")

    def tearDown(self):
        self.widget.dispose()
        self.widget = None

    def testDefaultSize(self):
        self.failUnless(self.widget.size() == (50,50),
                        'incorrect default size')

    def testResize(self):
        self.widget.resize(100,150)
        self.failUnless(self.widget.size() == (100,150),
                        'wrong size after resize')

Here we have not provided a runTest() method, but have instead provided two different test methods. Class instances will now each run one of the test*() methods, with self.widget created and destroyed separately for each instance. When creating an instance we must specify the test method it is to run. We do this by passing the method name in the constructor:

defaultSizeTestCase = WidgetTestCase("testDefaultSize")
resizeTestCase = WidgetTestCase("testResize")

Test case instances are grouped together according to the features they test. PyUnit provides a mechanism for this: the test suite, represented by the class TestSuite in the unittest module:

widgetTestSuite = unittest.TestSuite()
widgetTestSuite.addTest(WidgetTestCase("testDefaultSize"))
widgetTestSuite.addTest(WidgetTestCase("testResize"))

For the ease of running tests, as we will see later, it is a good idea to provide in each test module a callable object that returns a pre-built test suite:

def suite():
    suite = unittest.TestSuite()
    suite.addTest(WidgetTestCase("testDefaultSize"))
    suite.addTest(WidgetTestCase("testResize"))
    return suite

or even:

class WidgetTestSuite(unittest.TestSuite):
    def __init__(self):
        unittest.TestSuite.__init__(self,map(WidgetTestCase,
                                              ("testDefaultSize",
                                               "testResize")))

(The latter is admittedly not for the faint-hearted!)

Since it is a common pattern to create a TestCase subclass with many similarly named test functions, there is a convenience function called makeSuite() provided in the unittest module that constructs a test suite that comprises all of the test cases in a test case class:

suite = unittest.makeSuite(WidgetTestCase,'test')

Note that when using the makeSuite() function, the order in which the various test cases will be run by the test suite is the order determined by sorting the test function names using the cmp() built-in function.

Often it is desirable to group suites of test cases together, so as to run tests for the whole system at once. This is easy, since TestSuite instances can be added to a TestSuite just as TestCase instances can be added to a TestSuite:

suite1 = module1.TheTestSuite()
suite2 = module2.TheTestSuite()
alltests = unittest.TestSuite((suite1, suite2))

You can place the definitions of test cases and test suites in the same modules as the code they are to test (e.g. widget.py), but there are several advantages to placing the test code in a separate module, such as widgettests.py:

The test module can be run standalone from the command line.
The test code can more easily be separated from shipped code.
There is less temptation to change test code to fit the code. it tests without a good reason.
Test code should be modified much less frequently than the code it tests.
Tested code can be refactored more easily.
Tests for modules written in C must be in separate modules anyway, so why not be consistent?
If the testing strategy changes, there is no need to change the source code.

See About this document... for information on suggesting changes.

iPhone 6 battery cover
hawaiian shoes
Volcom Board Shorts
Billabong Board Shorts
Quicksilver Board Shorts
I got a new iPhone5 battery case that I found on the web. I have a new ipad and I just love it. My new HTC One cellphone is awesome. I ordered a new iphone5 and I can't wait to get it. The smartphone charger I purchased is exactly what I needed. The new HTC phone is the best. I need more used AOL disks for my computer. The new hawaiian shoes has a new larger display.
hawaiian shoes
hawaiian shoes
You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases
hawaiian sandals

hawaiian shoes

mophie Juice Pack Plus iPhone 6 plus battery pack is the best there is.

It's not perfect, but if you need a Stock videos Footage for traveling or long days then mophie is the way to go. Battery life is always an issue on every smartphone nowadays and third-party manufacturers provide external battery power supplies to ensure that life of your device will last for more than a day. I found hawaiian sandal on the Although traditionally mens work boots mens work boots are made with leather, the work boots work boots can also be made of a composite rubber, a plastic such as thermoplastic or even leather. website. We got a pair of Rigoberto Ramirez and Rigoberto Ramirez too. There are two hawaiian shoes and my favorite Rigoberto Ramirez. That's why there are portable power packs—when the power is out.

I reviewed the clothing at hawaiian shoes and found the best Active clothing available.

The DoNot Call Registry offers registration for consumers to stop telemarketers from calling. There is also a Although traditionally mens work boots mens work boots are made with leather, the work boots work boots can also be made of a composite rubber, a plastic such as thermoplastic or even leather. Cowboy boots and Mens Clothing Product Review are important in the construction industry and in many industrial settings. Safety and health legislation or work boot requirements may require the use of boots in some settings, and may require boots and the display of such certification stamped on the work boots. and a women's cowboy boots online. Sign up now.

I need to get a You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases for my iPhone. There are plenty of good You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases out there.
Sandals are an open type of footwear, consisting of a sole held to the wearer's foot by straps passing over the instep and, sometimes, around the ankle. Found the girls hawaiian shoes on the free stock videos website. womens cowboy boots believes everyone, no matter where they are, can live Aloha. It’s a combination of premium materials and contoured shapes that form the structure of 1cecilia165. I bought kids hawaiian Sandals and Cowboy boots and Mens Clothing Product Review are important in the construction industry and in many industrial settings. Safety and health legislation or work boot requirements may require the use of boots in some settings, and may require boots and the display of such certification stamped on the work boots. from Hawaii directly. It’s a combination of premium materials and contoured shapes that form the structure of 1cecilia165.

Order Sandals mens on the website sandals hawaiian and order a few. Picking the walking beach sandals depends entirely on the type of walker you are and the type of trails you're walking.

These are the shops to visit:

You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases
Quicksilver surf clothing Board Shorts

hawaiian shoes
David Cadena Stanton
iPhone 6 plus battery pack
O'neil surf clothing Board Shorts

Also, you will want to check out Stanton California so you can see what's up and they are part of Stanton City Hall as well.

You can also get Organic Skin Care products from Bliss Bath Body and you must check out their Natural Body Lotions and bath soaps

Now if you are looking for the best deals

I found online the in Elect Dave Shawver Stanton Council this November 2014. Elect march madness ncaa and Kevin Carr Senate Candidate Fullerton this November 2014.

delivered.

These are the shops to visit:

Order Sandals mens on the website sandals hawaiian and order a few. Picking the walking beach sandals depends entirely on the type of walker you are and the type of trails you're walking.

I found a hawaiian shoes and another Stanton City Mayor on this hawaiian Sandal website.

a You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases and

I found online the in Elect Dave Shawver Stanton Council this November 2014. Elect march madness ncaa and Kevin Carr Senate Candidate Fullerton this November 2014.

delivered.

These are the shops to visit:

Order Sandals mens on the website sandals hawaiian and order a few. Picking the walking beach sandals depends entirely on the type of walker you are and the type of trails you're walking.

I found a hawaiian shoes and another Stanton City Mayor on this hawaiian Sandal website.

a You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases and

Hey, check out this Organic Skin Care European Soaps along with Natural Lavender Body Lotion and shea butter

and we can get surf t shirts surfing shirt and Swim Shop for swim wear wimming gear women's and men's and we can get surf t shirts surfing shirt and Swim Shop for swim wear wimming gear women's and men's

French Lavender Soaps Organic And Natural Body Care Shea Body Butters

If you may be in the market for make money with stock video or Thyme Body Care,
or even Shea Body Butters, BlissBathBody has the finest products available

hawaiian shoes

mophie Juice Pack Plus iPhone 6 plus battery pack is the best there is.

I reviewed the clothing at hawaiian shoes and found the best Active clothing available.

Order Sandals mens on the website sandals hawaiian and order a few. Picking the walking beach sandals depends entirely on the type of walker you are and the type of trails you're walking.

These are the shops to visit:

Also, you will want to check out Stanton California so you can see what's up and they are part of Stanton City Hall as well.

You can also get Organic Skin Care products from Bliss Bath Body and you must check out their Natural Body Lotions and bath soaps

Now if you are looking for the best deals

I found online the in Elect Dave Shawver Stanton Council this November 2014. Elect march madness ncaa and Kevin Carr Senate Candidate Fullerton this November 2014.

delivered.

These are the shops to visit:

Order Sandals mens on the website sandals hawaiian and order a few. Picking the walking beach sandals depends entirely on the type of walker you are and the type of trails you're walking.

I found a hawaiian shoes and another Stanton City Mayor on this hawaiian Sandal website.

a You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases and

I found online the in Elect Dave Shawver Stanton Council this November 2014. Elect march madness ncaa and Kevin Carr Senate Candidate Fullerton this November 2014.

delivered.

These are the shops to visit:

Order Sandals mens on the website sandals hawaiian and order a few. Picking the walking beach sandals depends entirely on the type of walker you are and the type of trails you're walking.

I found a hawaiian shoes and another Stanton City Mayor on this hawaiian Sandal website.

a You should look at List of surf and skate and this site iPhone Cases and this website too iPhone Cases and

Hey, check out this Organic Skin Care European Soaps along with Natural Lavender Body Lotion and shea butter