Helper Methods

TripalTestSuite provides a set of helper methods to automate tedious aspects of testing.

Silently Testing Printed Output

Since tests should run “silently”, i.e. without printing output to the screen, we’d have to create an output buffer to collect printed strings into a variable. In PHP, this can be done as such:

// Supress tripal errors

// Run the call
echo "testing";
$output = ob_get_contents();

// Clean the buffer and unset tripal errors suppression

However, TripalTestSuite provides a silent() method that automates this process, provides helpful assertions and supports larger strings. Example usage:

$output = silent(function() {
  echo "testing";
$output->assertSee('testing'); // true!


This method has a maximum string size to avoid memory leaks. The size is set in PHP’s ini file as output_buffering, which by default is set to 4KB. If you would like to collect larger strings, you must adjust your PHP settings.

Assertions and Methods

The silent method returns a SilentResponse which provides the following methods.

Method Arguments Description
assertSee() $value mixed Asserts that the given value is present in the suppressed printed output
assertReturnEquals() $value mixed
Asserts that the given value equals the returned value from the called function
assertJsonStructure() $strcture array<br>``$data`` array Optional Asserts that the given stricture matches that of the suppressed printed output
getContent() None Get the suppressed printed content as a string
getReturnValue() None Get the returned value from the called function


$output = silent(function() {
        drupal_json_output(['key' => 'value']);
        return true;


You can also call methods directly in the Callable function:

// Assume we have the following function
function tripal_print_message($message) {
  echo $message;

$output = silent(function() {
  tripal_print_message('tripal test suite');

// Get the output as a string
$rawOtput = $output->getContent();

Access Private and Protected Properties and Methods of Objects

TripalTestSuite provides a reflect() method that accepts an object and makes all of the properties and methods public and available for testing. Assume we have the following class:

class PrivateClass
        private $private;

        public function __construct($private = 'private')
                $this->private = $private;

        protected function myProtected()
                return 'protected';

        private function privateWithArgs($one, $two)
                return $one.' '.$two;

Because of the functions and properties of the class are private or protected, we normally would not be able to access any of them. However, we can force access using the reflect helper. See below for an examples.

Accessing Private and Protected Methods

// Pass an initialized class to the reflect method
$myObject = new PrivateClass();
$privateClass = reflect($myObject);

// Accessing protected methods
$value = $privateClass->myProtected();
$this->assertEquals('protected', $value);

// Accessing private methods with arguments
$value = $privateClass->privateWithArgs('one', 'two');
$this->assertEquals('one two', $value);

Accessing Properties

// Pass an initialized class to the reflect method
$myObject = new PrivateClass();
$privateClass = reflect($myObject);

$this->assertEquals('private', $privateClass->private);