Software testing has been around for decades, and it has been proven to provide many crucial benefits, including:
- Reducing the number of bugs and regressions
- Increasing project velocity (in the long run)
- Improving accuracy of scheduling estimates
- Saving time and money
- Increasing user trust and satisfaction
You should use automated testing. Do not fall prey to common rationalizations and excuses relating to insufficient time, money, or resources. Time spent developing tests is repaid ten fold.
Quality is the ally of schedule and cost, not their adversary. If we have to sacrifice quality to meet schedule, it’s because we are doing the job wrong from the very beginning.
-- James A. Ward
The bitterness of poor quality remains long after the sweetness of meeting the schedule has been forgotten.
-- Karl Wiegers
That being said, two important pitfalls should be acknowledged:
- It is possible to do automated testing incorrectly such that it is too expensive. See Why Test Automation Costs Too Much.
- It is possible to write automated tests that have little value.
To avoid these pitfalls, follow the best practices outlined in sections below.
This directory contains all projects tests, grouped by testing technology. For all configuration related to builds that actually run these tests, please see the blt directory.
tests
├── behat - contains all Behat tests
│ ├── features
│ │ ├── bootstrap
│ │ └── Example.feature
│ ├── behat.yml - contains behat configuration common to all behat profiles.
│ └── integration.yml - contains behat configuration for the integration profile, which is used to run tests on the integration environment.
└── phpunit - contains PHPUnit tests for the project (Drupal PHPUnit tests should reside within a given Drupal module).
Additional technologies (some of which may not be supported by BLT) can also have their tests bundled in the tests folder for convenience (e.g. tests/jmeter
).
BLT also supports the bundling and execution of phpunit tests from locations outside of the tests folder. See the PHPUnit Configuration section below for additional information.
Before attempting to execute any tests, verify that composer dependencies are built by running composer install
in the project root.
The following testing commands are available:
blt tests:all
blt tests:behat:run
blt tests:phpunit:run
blt tests:drupal:run
blt tests:security:check:updates
blt tests:security:check:composer
See Extending BLT for more information on overriding default configuration values.
For more information on the commands, run:
./vendor/bin/phpunit --help
./vendor/bin/behat --help
The high-level purpose of BDD is to create a strong connection between business requirements and the actual tests. Behat tests should mirror ticket acceptance criteria as closely as possible.
Consequently, proper Behat tests should be written using business domain language. The test should be comprehensible by the stakeholder and represent a clear business value. It should represent a typical user behavior and need not be an exhaustive representation of all possible scenarios.
See referenced materials for more information on BDD best practices.
To execute a single feature:
blt tests:behat:run -D behat.paths=${PWD}/tests/behat/features/Examples.feature
# Relative paths are assumed to be relative to tests/behat/features.
blt tests:behat:run -D behat.paths=Examples.feature
To execute a single scenario:
blt tests:behat:run -D behat.paths=${PWD}/tests/behat/features/Examples.feature:4
# Relative paths are assumed to be relative to tests/behat/features.
blt tests:behat:run -D behat.paths=Examples.feature:4
Where "4" is the line number of the scenario in the feature file.
To execute the tests directly (without BLT) see the following examples:
./vendor/bin/behat -c tests/behat/local.yml tests/behat/features/Examples.feature -p local
Configuration for the BLT Behat commands is stored in the behat
configuration variable. You can modify the behavior of the BLT tests:behat:run
target by customizing this configuration. See Extending BLT for more information on overriding configuration variables.
Behat's own configuration is defined in the following files:
- tests/behat/behat.yml
- tests/behat/example.local.yml
- tests/behat/local.yml
Configuring BLT Behat commands for a multisite setup may require some adjustments to the standard local.yml
file and in some case may require the use of a site-specific configuration file per multisite. See Override BLT variables in docroot/sites/{newsite}/blt.yml for more information on configuring Behat per multisite.
BLT includes the Behat ScreenshotExtension, configured by default to store a screenshot of any failed step locally. You can configure the extension globally under the Bex\Behat\ScreenshotExtension
key in tests/behat/behat.yml
, or override locally inside tests/behat.local.yml
.
Read through the ScreenshotExtension documentation to discover how to change where images are saved, disable the extension, or change the screenshot taking mode.
- Behat tests must be used behaviorally, i.e., they must use business domain language.
- Each test should be isolated, i.e., it should not depend on conditions created by another test. In pratice, this means:
- Resetting testing environment via CI after test suite runs
- Defining explicit cleanup tasks in features
- @todo add examples of good and bad features
- Writing Behat tests that do not use business domain language.
- Tests are not sufficiently isolated. Making tests interdependent diminishes their value!
- Writing tests that are exhaustive of all scenarios rather than representative of a typical scenario.
- Writing Behat tests when a unit test should be employed.
- Google Chrome is missing: BLT currently expects Google Chrome (more exactly, the
google-chrome
binary) to be available on the local setup. If you're using a Mac and Chrome is installed, you should be good to go. Similarly, BLT includes the Chrome binary in DrupalVM. If you are running BLT in another Linux environment, installchromium-driver
. - Spotting bad configuration: In order to troubleshoot your Behat setup, make sure to run
blt doctor --site=mysite.local
to try and spot any obvious issue. - Multisite / ACSF issues: When you need to run tests with any authenticated user role, you may have to uninstall
simplesamlphp_auth
. Else, Behat tests may hang. When ready, runblt behat --site=mysite.local
from within the project root. If running Behat tests fail, then it means you either have issues with your BLT / Behat setup or there's an issue with tests themselves.
- Cucumber - Where to start? Note that Cucumber is simply a Ruby based BDD library, whereas Behat is a PHP based BDD library. Best practices for tests writing apply to both.
- The training wheels came off
- Tests should not contain any control statements.
- Be careful to make both positive and negative assertions of expectations.
- @todo add examples of good and bad tests.
- Writing unit tests that are not independent.
- Making unit tests too large. Tests should be small and granular.
- Asserting only positive conditions. Negative assertions should also be made.
- Drupal's implementation of PHPUnit
- Presentations on PHPUnit
- Test Driven Development: By Example (book)
- xUnit Test Patterns: Refactoring Test Code (book for the really serious)
- Unit testing: Why bother?
The tests
configuration variable has following properties:
reports.localDir
: Directory used to save testing reports on local environmentsreports.remoteDir
: Directory used to save testing reports on remote environmentsrun-server
: Whether or not to launch the Drush server for testingserver.port
: The Drush run-server port, default is8888
server.url
: The URL for Drush server, default ishttp://127.0.0.1:8888
selenium.port
: Port for Selenium, default is4444
selenium.url
: URL for Selenium, default ishttp://127.0.0.1:4444/wd/hub
chrome.port
: Port forchrome
browser, default is9222
chrome.args
: Args forchrome
browser, default isnull
chromedriver.port
: Port forchromedriver
WebDriver for Chrome, default is9515
chromedriver.args
: Args forchromedriver
WebDriver for Chrome, default isnull
Project level, functional PHPUnit tests are included in tests/phpunit
. Any PHPUnit tests that affect specific modules or application level features should be placed in the same directory as that module or feature code, not in this directory.
You can customize the tests:phpunit:run
command by modifying BLT Configuration for the tests:phpunit
key.
Each row under the tests:phpunit
key should contain a combination of the following properties:
bootstrap
: A "bootstrap" PHP file that is run before the testsclass
: the class name for the testconfig
: path to either the Core phpunit configuration file (docroot/core/phpunit.xml.dist) or a custom one. If left blank, no configuration will be loaded with the unit test.debug
: iftrue
, will display debugging informationdirectory
: directory to scan for testsexclude
: run tests excluding any tagged with this@group
file
: the sourcefile that declares the class provided inclass
filter
: allows text filter for testsgroup
: run tests only tagged with a specific@group
path
: the directory where the phpunit command will be run fromprinter
: the TestListener implementation to usestop-on-error
: iftrue
, will stop execution upon first errorstop-on-failure
: iftrue
, sill stop execution upon first error or failuretestdox
: iftrue
, report test execution progress in TestDox formattestsuite
: run tests that are part of a specific@testsuite
testsuites
: (array) run tests from multiple@testsuite
s (takes precedence overtestsuite
)
See PHPUnit's documentation for additional information.
tests:
phpunit:
- # Run BLT"s example test.
path: '${repo.root}/tests/phpunit'
config: '${docroot}/core/phpunit.xml.dist'
class: 'ExampleTest'
file: 'ExampleTest.php'
Each row under the tests:drupal
key should contain a combination of the following properties (see Drupal's core/phpunit.xml.dist
for additional details):
test-runner
: Whether to run Drupal tests with PHPUnit (phpunit
) or Drupal's run-tests.sh script (run-tests-script
)sudo-run-tests
: Whether or not to use sudo when running Drupal testsweb-driver
: WebDriver to use for running Drupal's functional JavaScript tests (onlychromedriver
is supported at this time)browsertest-output-directory
: Directory to write output for browser tests (value forBROWSERTEST_OUTPUT_DIRECTORY
)apache-run-group
: Unix user used for tests (value forAPACHE_RUN_USER
)apache-run-user
: Unix group used for tests (value forAPACHE_RUN_GROUP
) (ifsudo-run-tests:true
, this is used to run testing commands assudo -u www-data -E ./vendor/bin/phpunit {...}
)mink-driver-args
: Driver args to mink tests (value forMINK_DRIVER_ARGS
)mink-driver-args-webdriver
: Driver args to webdriver tests (value forMINK_DRIVER_ARGS_WEBDRIVER
)mink-driver-class
: Driver class for mink tests (value forMINK_DRIVER_CLASS
)simpletest-base-url
: Base URL for Simpletest (value forSIMPLETEST_BASE_URL
)simpletest-db
: Connection string Simpletest database (value forfor SIMPLETEST_DB
)symfony-deprecations-helper
: Setting todisabled
disables deprecation testing completely (value forSYMFONY_DEPRECATIONS_HELPER
)phpunit
: Tests to run using Drupal's implementation of PHPUnit. This requires Drupal to be installed.drupal-tests
: Tests to run with Drupal's run-test.sh script.
tests:
drupal:
phpunit:
- # Run Drupal' unit, kernel, functional, and functional-javascript testsuites for the action module.
path: '${docroot}/core'
config: ${docroot}/core/phpunit.xml.dist
testsuites:
- 'unit'
- 'kernel'
- 'functional'
- `functional-javascript`
group: action
- # Run all tests in the custom modules directory.
path: '${docroot}/core'
config: ${docroot}/core/phpunit.xml.dist
directory: ${docroot}/modules/custom
Note that Selenium is required to run Drupal tests, and Acquia Pipelines does not support Selenium (since it does not have Java installed). Thus, you cannot run these tests on Pipelines. You can still run the rest of the test suite (Behat, PHPUnit, etc...) using Chrome.
You can customize the tests:drupal:run
command by modifying BLT Configuration for the tests:run-tests
key.
Each row under the tests:drupal-tests
key should contain a combination of the below properties. See Drupal's documentation for a description of each properties.
all
browser
clean
color
concurrency
dburl
die-on-fail
directory
keep-results-table
keep-results
repeat
sqlite
suppress-deprecations
tests
(array)types
(array, takes precedence overtype
)type
url
tests:
drupal:
drupal-tests:
- # Run the PHPUnit-Unit, PHPUnit-Kernel, and PHPUnit-Functional test types for the action module.
color: true
concurrency: 2
types:
- 'PHPUnit-Unit'
- 'PHPUnit-Kernel'
- 'PHPUnit-Functional'
tests:
- 'action'
sqlite: '${tests.drupal.sqlite}'
url: '${tests.drupal.simpletest-base-url}'
- # Run the PHPUnit-FunctionalJavascript test type for the action module.
color: true
concurrency: 1
types:
- 'PHPUnit-FunctionalJavascript'
tests:
- 'action'
sqlite: '${tests.drupal.sqlite}'
url: '${tests.drupal.simpletest-base-url}'
- # Run the Simpletest test type for the user module.
color: true
concurrency: 1
types:
- 'Simpletest'
tests:
- 'user'
sqlite: '${tests.drupal.sqlite}'
url: '${tests.drupal.simpletest-base-url}'
BLT supports a frontend-test
target that can be used to execute a variety of testing frameworks. Examples may include Jest, Jasmine, Mocha, Chai, etc.
You can customize the configuration values for the frontend-test
key to enable this capability of BLT.