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The goal of the style guide is to try provide rules to write code that looks the same no matter what project. It is a guide and is always up for discussion by the team. We have created [https://github.com/mozilla/mozwebqa-test-templates templates] based on the details below.
The goal of the style guide is to try provide rules to write code that looks the same no matter what project. It is a guide and is always up for discussion by the team.


= All Files =
= All Files =


== File Headers ==
== File Headers ==
* At the top of each file should have python file header
* Each file should have a completed copy of the [http://www.mozilla.org/MPL/2.0/ MPL2] license block, immediately followed by an empty line.
<pre class="brush:py;toolbar:false;">
    #!/usr/bin/env python
</pre>
* Each file should have a completed copy of the [http://www.mozilla.org/MPL/2.0/ MPL2] license block, immediately preceded and followed by an empty line.
* Each file should pass [http://www.python.org/dev/peps/pep-0008/ PEP8] except for line length, see below.   
* Each file should pass [http://www.python.org/dev/peps/pep-0008/ PEP8] except for line length, see below.   
<pre class="brush:py;toolbar:false;">
    # Good
    def method(self, parameter)


    # Bad
<source lang="python">
    def method(self,parameter)
# Good
</pre>
def method(self, parameter)
 
# Bad
def method(self,parameter)
</source>
 
* Lines should try not to have more than 100 characters.
* Lines should try not to have more than 100 characters.
* Docstrings should conform to [http://www.python.org/dev/peps/pep-0257/ PEP0257] and should be on a single line wherever possible.
* Docstrings should conform to [http://www.python.org/dev/peps/pep-0257/ PEP0257] and should be on a single line wherever possible.
<pre class="brush:py;toolbar:false;">
    # Good
    def click_login():
    """Clicks the login link."""


    # Bad
<source lang="python">
    def click_login():
# Good
    """
def click_login():
    Clicks the login link.
"""Clicks the login link."""
    """
 
</pre>
# Bad
def click_login():
"""
Clicks the login link.
"""
</source>
 
Where not possible, the first line should be a summary.
Where not possible, the first line should be a summary.
<pre class="brush:py;toolbar:false;">
    # Good
    def login():
    """Logs in.


    Clicks the login link and then waits for the home page to load.
<source lang="python">
# Good
def login():
"""Logs in.


    """
Clicks the login link and then waits for the home page to load.
 
"""
 
# Bad
def login():
"""Logs in.
Clicks the login link and then waits for the home page to load."""
</source>


    # Bad
    def login():
    """Logs in.
    Clicks the login link and then waits for the home page to load."""
</pre>
* Indenting should be a soft tab (4 spaces) as common with in Python. Do not mix tabs and spaces!
* Indenting should be a soft tab (4 spaces) as common with in Python. Do not mix tabs and spaces!
* There should be no whitespace at the end of the file (as per PEP8)
* There should be no whitespace at the end of the file (as per PEP8).
* Comments should be on the line above. Remember to update comments when changing code so that code matches the comments.
* Comments should be on the line above. Remember to update comments when changing code so that code matches the comments.
* Class names should be in Pascal style as this is Python idiomatic.
* Class names should be in Pascal style as this is Python idiomatic.
<pre class="brush:py;toolbar:false;">
 
    # Good
<source lang="python">
    class TestThisSite:
# Good
class TestThisSite:
      
      
    # Bad
# Bad
    class test_this_site:
class test_this_site:
</pre>
</source>


= Page Objects =
= Page Objects =
== General ==
== General ==
* All Page Objects should inherit from Page in page.py.
* All page objects should inherit from <code>Page</code> in page.py.
* Page Objects should not do asserts. This should be done within the test.
* Page objects should not do asserts. This should be done within the test.
* Each Page should be grouped within one module.
* Each page should be grouped within one module.
* If using mutliple words to describe a module separate them with underscores '_'
* If using multiple words to describe a module separate them with underscores '_'
    test_search.py
* Timeout time should be taken from pytest-mozwebqa via <code>page.py's</code> timeout property.
* Timeout time should be taken from pytest-mozwebqa via page.py's timeout property.
* Single quotes (') should be used instead of double (") throughout.
* Single quotes (') should be used instead of double (") throughout.
* Methods should have a single purpose
* Methods should have a single purpose.


== Logic ==
== Logic ==
* Methods should not contain logic that depends on properties of the page. The logic and expectations should be within the test, and adding this to the page object could guard your tests against genuine failures.
* Methods should not contain logic that depends on properties of the page. The logic and expectations should be within the test, and adding this to the page object could guard your tests against genuine failures.
<pre class="brush:py;toolbar:false;">
 
    # Good
<source lang="python">
     def click_login(self)
# Good
def click_login(self)
     self.selenium.find_element(*self._login_locator).click()
 
# Bad
def click_login(self)
    if not self.is_user_logged_in:
         self.selenium.find_element(*self._login_locator).click()
         self.selenium.find_element(*self._login_locator).click()
 
     else:
     # Bad
         pass
    def click_login(self)
</source>
        if not self.is_user_logged_in:
            self.selenium.find_element(*self._login_locator).click()
         else:
            pass
</pre>


== Locators ==
== Locators ==
* Locator variables should be prefixed with _ to show that it is "[http://docs.python.org/tutorial/classes.html#private-variables private]".
* Locator variables should be prefixed with <code>_</code> to show that it is [http://docs.python.org/tutorial/classes.html#private-variables private].
* Variables should be descriptive of the area and not clash with any properties.
* Variables should be descriptive of the area and not clash with any properties.
* Suffix of _locator.
* Should have a suffix of <code>_locator</code>.
* Accessing locators should be done through a property or method as this keeps the locator as readonly.
* Accessing locators should be done through a property or method as this keeps the locator as read-only.
<pre class="brush:py;toolbar:false;">
 
    @property
<source lang="python">
    def search_term(self):
@property
        return self.selenium.find_element(*self._search_box_locator).value
def search_term(self):
</pre>
    return self.selenium.find_element(*self._search_box_locator).value
</source>
 
* We should use locators in the following order of preference (there will be exceptions):
* We should use locators in the following order of preference (there will be exceptions):
** ID
** ID
Line 99: Line 105:
** CSS selector
** CSS selector
** XPath
** XPath
* For Selenium RC, locators should include the strategy instead of using implied strategies.
<pre class="brush:py;toolbar:false;">
    # Good
    _my_locator = "id=content"
   
    # Bad
    _my_locator = "content"
</pre>
* CSS locators should use whitespace for readability when using direct descendants.
* CSS locators should use whitespace for readability when using direct descendants.
<pre class="brush:py;toolbar:false;">
 
    # Good
<source lang="python">
    _my_locator = "css=#content > p > a"
# Good
_my_locator = "css=#content > p > a"
      
      
    # Bad
# Bad
    _my_locator = "css=#content>p>a"
_my_locator = "css=#content>p>a"
</pre>
</source>
* With WebDriver, use a Python tuple to define locators:
 
<pre class="brush:py;toolbar:false;">
* Use Python tuples to define locators:
    # Good
 
    _my_locator = (By.ID, "content")
<source lang="python">
</pre>
# Good
_my_locator = (By.ID, "content")
</source>


== Actions ==
== Actions ==
* Methods that perform actions on the page should indicate the action in the method name.
* Methods that perform actions on the page should indicate the action in the method name.
<pre class="brush:py;toolbar:false;">
    # Good
    def click_report_with_length(length)


    # Bad
<source lang="python">
    def report_length(length)
# Good
</pre>
def click_report_with_length(length)
 
# Bad
def report_length(length)
</source>
 
* Actions should wait for the appropriate action to complete. This could be an implicit or explicit wait. For example, clicking a login button might explicitly wait for a username field to be visible.
* Actions should wait for the appropriate action to complete. This could be an implicit or explicit wait. For example, clicking a login button might explicitly wait for a username field to be visible.


Line 136: Line 139:


A brief example:
A brief example:
<pre class="brush:py;toolbar:false;">
 
<source lang="python">
class BasePage(Page):
class BasePage(Page):


Line 149: Line 153:
         @def click_login(self):
         @def click_login(self):
             self.selenium.find_element(*self._login_link).click()
             self.selenium.find_element(*self._login_link).click()
</pre>
</source>


Referring to this page region with a property makes it very readable and concise from within the test. Clicking login during a test would be performed like this:
Referring to this page region with a property makes it very readable and concise from within the test. Clicking login during a test would be performed like this:
<pre class="brush:py;toolbar:false;">
<source lang="python">
    my_page.header.click_login()
my_page.header.click_login()
</pre>
</source>


Another example where this might be used is on a search results page, the page region being the search results element.
Another example where this might be used is on a search results page, the page region being the search results element.
Line 162: Line 166:
     test_search.py
     test_search.py
* Test method signature should include mozwebqa to use pytest-mozwebqa plugin.
* Test method signature should include mozwebqa to use pytest-mozwebqa plugin.
<pre class="brush:py;toolbar:false;">
 
    def test_example(self, mozwebqa):
<source lang="python">
</pre>
def test_example(self, mozwebqa):
</source>
 
* Test method names should always show the intent of the test case.
* Test method names should always show the intent of the test case.
<pre class="brush:py;toolbar:false;">
    # Good
    def test_that_advanced_search_does_not_find_item(self, mozwebqa):


    # Bad
<source lang="python">
    def test_advanced_search(self, mozwebqa):
# Good
</pre>
def test_that_advanced_search_does_not_find_item(self, mozwebqa):
 
# Bad
def test_advanced_search(self, mozwebqa):
</source>
 
== Assertions ==
 
* Tests should handle the asserts -- not the page objects.
* Tests should handle the asserts -- not the page objects.
* Tests should use Python's native [https://docs.python.org/2/reference/simple_stmts.html#the-assert-statement assert] statement.
** Note that this is a change from our previous standard of using the [https://wiki.mozilla.org/Web_Testing/Automation/UnittestZero UnittestZero] package.
* When doing equivalency assertions, put the expected value first, followed by the actual value, for example:
<source lang="python">
assert 'expected' == 'actual'  # good
assert 'actual' == 'expected'  # bad
</source>
* When doing negative equivalency, use != and put the unexpected value first, followed by the actual value, for example:
<source lang="python">
assert 'unexpected' != 'actual'  # good
assert 'actual' != 'unexpected'  # bad
</source>
* To directly cause a test to fail raise an AssertionError with an appropriate message, for example:
<source lang="python">
raise AssertionError('message')
</source>
* See [http://pytest.org/latest/assert.html pytest's documentation on asserts] for more help.


= Size of patches =
= Size of patches =
Line 181: Line 208:
As we (and Selenium and automation) develop more knowledge some projects might fall behind the standards in this style guide. It can be tempting to want to fix all of the outdated style but in order to keep patches/pulls small (see above!) we are happy to have new and old standards of code sit side by side. As we regularly review and update tests the project will be brought completely up to our current standards.
As we (and Selenium and automation) develop more knowledge some projects might fall behind the standards in this style guide. It can be tempting to want to fix all of the outdated style but in order to keep patches/pulls small (see above!) we are happy to have new and old standards of code sit side by side. As we regularly review and update tests the project will be brought completely up to our current standards.


Or if you prefer, log a Github issue to have a section of code addressed separately to the job you are doing.
Or if you prefer, log a GitHub issue to have a section of code addressed separately to the job you are doing.
Jlorenzo
Confirmed users
213

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