O Guia Definitivo do Yii 1.1

In this class, we specify the fixtures member variable to be an array that specifies which
fixtures will be used by this test. The array represents a mapping from fixture names to
model class names or fixture table names (e.g. from fixture name posts to model class
Post). Note that when mapping to fixture table names, we should prefix the table name
with a colon (e.g. :Post) to differentiate it from model class name. And when using model
class names, the corresponding tables will be considered as fixture tables. As we
described earlier, fixture tables will be reset to some known state each time when a test
method is executed.
Fixture names allow us to access the fixture data in test methods in a convenient way. The
following code shows its typical usage:
// return all rows in the 'Comment' fixture table
$comments = $this->comments;
// return the row whose alias is 'sample1' in the `Post` fixture table
$post = $this->posts['sample1'];
// return the AR instance representing the 'sample1' fixture data row
$post = $this->posts('sample1');
Note: If a fixture is declared using its table name (e.g. 'posts'=>':Post'), then the third
usage in the above is not valid because we have no information about which model
class the table is associated with.
Next, we write the testApprove method to test the approve method in the Comment model
class. The code is very straightforward: we first insert a comment that is pending status;
we then verify this comment is in pending status by retrieving it from database; and finally
we call the approve method and verify the status is changed as expected.