Thank you for your interest in contributing to AssertJ assertions!
We appreciate your effort and to make sure that your pull request is easy to review, we ask you to make note of the following guidelines:
- Use AssertJ code Eclipse formatting preferences (for IntelliJ IDEA users, you can import it)
- Write complete Javadocs for each assertion method and include a code example.
- Write one JUnit test class for each assertion method with the following naming convention:
<AssertClass>_<assertion>_Test
. - Unit tests method naming convention is underscore-based (like python) and not camel-case, we find it is much readable for long test names!
- Successful assertion unit test method name must start with:
should_pass_...
. - Failing assertion unit test method name must start with:
should_fail_...
. - If possible, add a (fun) code example in assertj-examples and use it in the javadoc.
assertj-examples shows how to use efficiently AssertJ through fun unit test examples, it can be seen as AssertJ living documentation.
Here some of ThrowableAssert
assertions: hasMessage
, hasNoCause
, hasMessageContaining
, for each of them we have a test class, note the naming convention:
ThrowableAssert_hasMessage_Test
ThrowableAssert_hasNoCause_Test
ThrowableAssert_hasMessageContaining_Test
Let's look at Throwables_assertHasNoCause_Test
tests method names (underscore based only):
should_pass_if_actual_has_no_cause
should_fail_if_actual_is_null
should_fail_if_actual_has_a_cause
A good javadoc example taken from AbstractCharSequenceAssert.containsSequence
including:
- assertion description
- a code example showing how to use the assertion
- parameters description (if any)
- exceptions description
/**
* Verifies that the actual {@code CharSequence} contains all the given strings <b>in the given order</b>.
* <p>
* Example:
*
* <pre>
* String book = "{ 'title':'A Game of Thrones', 'author':'George Martin'}";
*
* // this assertion succeeds ...
* assertThat(book).containsSequence("{", "title", "A Game of Thrones", "}");
*
* // ... but this one fails as "author" must come after "A Game of Thrones"
* assertThat(book).containsSequence("{", "author", "A Game of Thrones", "}");
* </pre>
*
* @param values the Strings to look for, in order.
* @return {@code this} assertion object.
* @throws NullPointerException if the given values is {@code null}.
* @throws IllegalArgumentException if the given values is empty.
* @throws AssertionError if the actual {@code CharSequence} is {@code null}.
* @throws AssertionError if the actual {@code CharSequence} does not contain all the given strings <b>in the given order</b>.
*/
Not all AssertJ javadoc meets this standard but this is something we are working on.