Manual:PHP unit testing/Writing unit tests/ja

PHPUnit マニュアルは、単体テストを理解および開発するための優れた手順を提供します. テストの記述および整理の節に特に注意してください.

Developing best practices
MediaWiki での単体テストに不慣れな開発者は、出発点として を使用する必要があります. これには、単体テストの作成方法を学ぶ過程を容易にする役立つコメントが含まれています.

もう 1 つのリソースは、OSCON 2010 で Sebastian Bergmann が行った PHPUnit の成功事例トークのスライドです.

Developers should avoid inventing new conventions or borrowing conventions from other frameworks; using the already well-established PHPUnit conventions will serve to make MediaWiki's tests both useful and usable.

Unit tests should follow A Set of Unit Testing Rules by Michael Feathers.



テスト可能なコードを書く
MediaWiki はテスト可能であることを目的として書かれていません. あらゆる場所でグローバル変数を使用し、多くの場所で静的メソッドを使用します. これは我々が受け入れなければならない遺産ですが、これらのことを新しいコードに導入しないようにし、今後変更するよう心がけてください.

Miško Hevery のリソース Guide to Testability が役立つかもしれません. (Miško Hevery は Google のアジャイル コーチ [の 1 人?] です. )



テストの規約
ファイル名は  で終わる必要があります. 出発点として を使用します.



setUp と tearDown

 * Must be  functions.
 * tearDown should be in the opposite order of setUp.
 * setUp starts with calling its parent.
 * tearDown ends with calling its parent.

Assertion functions

 * Must be  functions.
 * The name of the function should be in lowerCamelCase and begin with the word ; e.g.,.
 * Whenever possible, refer to the most important method being tested; e.g.,  is tested in.

Data providers

 * Must be  functions.
 * The name of the data provider should be in lowerCamelCase and begin with the word ; e.g.,.
 * Should not instantiate MediaWiki Services, since data providers are called before . For example, instead of , use   to avoid creating a.

Telling a story
Test output should tell a story. The  output format is a good way to view this story: a test suite execution is displayed as a set of statements about the test classes, along with whether or not they have passed. The statements (unless customized) are the test method names with corrected capitalization and spacing.

The  annotation can be used to customize the message that is displayed. It is not currently used in the MediaWiki codebase.

See "Other Uses for Tests" for more information.

Number of assertions
Only one assertion per test unless there is a good reason (expensive tests may need to be grouped).

Grouping tests
PHPUnit allows tests to be put into arbitrary groups. Groups of tests can be selected for execution or excluded from execution when the test suite is run (see the @group annotation, The Command-Line Test Runner and XML Configuration File documentation in the PHPUnit manual for additional details.)

To add a test (or class) to a group, use the  annotation in the docblock preceding the code. 例:

Several functional groups are currently used in MediaWiki unit tests:


 * API - Tests that exercise the MediaWiki API.
 * Broken - Put broken tests into group Broken. Tests in this group will not be run (as is configured in ).
 * Database - Tests that require database connectivity should be put into group Database. NOTE: this causes temporary tables to be overlayed over the real wiki database, so test cases can perform database operations without changing the actual wiki.
 * Destructive - Tests that alter or destroy data should be put into group Destructive.
 * Search - Tests that use MediaWiki's built-in search put into group Search.
 * SeleniumFramework - Tests that require SeleniumFramework to be installed should be put in group SeleniumFramework.
 * Stub - Put test stubs into group Stub. Tests in this group will not be run (as is configured in ).
 * sqlite - Tests that use SQLite should be put into group sqlite.
 * Upload - Tests that upload files should be put into group Upload.
 * Utility - Currently unused by any test. Tests in this group will be not be run (as is configured in ).

In addition, tests may also be grouped based on development team:


 * Fundraising
 * EditorEngagement
 * Internationalization
 * etc.

To test only a particular group, use the  flag from the command line:

php phpunit.php --group Search

or if you use the Makefile in core/tests/phpunit:

make FLAGS="--group Search" target

where target can be phpunit, safe, etc.

カバー率
The PHPUnit documentation has a chapter about coverage. There is a coverage report for mediawiki core generated twice a day. As the forceCoversAnnotation option should be in effect the test should be marked with @covers annotations to express which parts of the code the test actually checks (as opposed to code that is just run but whose results are never tested for with assertions).

Note that  requires fully-qualified class names (unlike  annotations such as  ).

データベース
When testing database-dependent code, you should put your test case in the Database group (see above). That tells MediaWikiTestCase to setup a  database connection for you to use in. Normally, this uses a separate temporary database, with certain limited data prefilled by, including a 'UTSysop' user and a 'UTPage' title. A test case can add additional data to the database by overriding  (which by default does nothing).

If you want to use another DB table (say, for your extension), it is not available by default for testing. To add the table to the temporary database constructed during testing, you need to add it to, for example:

However, please note that only the table schema is copied over from your actual database, not the existing data in that table.

You can directly test the current contents of the database with.

Here are some examples from extensions that you can look at for reference:


 * - from Extension:BounceHandler
 * - from Extension:PageAssessments

Tests that are not in the Database group still run against a temporary cloned database (even if they ignore  and instead use e.g.   directly); however, this database is only set up once for the whole test run, and not reset between test runs. Tests should avoid relying on this safety feature if possible.



メンテナンス スクリプト
Test cases for should inherit from, to handle the different output channels used by maintenance scripts.

The base test case  method will instantiate your   object for you, if you specify the class to construct by providing the mandatory   in your subclass:

In the unlikely event that you want to do something special to instantiate the class under test, you can override the  method, but hopefully this isn't needed.

By default, the maintenance script output will be suppressed and ignored. If you wish to test output (this is a good idea), use code like:

Failing
Usually tests code shouldn't do, but use the phpunit fail method:

This would show up as a failure in the testing summary rather than bringing the whole test suite down.