question/type/essay/tests/question_test.php

    /**
     * Test the behaviour of summarise_response().
     *
     * @dataProvider  summarise_response_text_attachments_provider
     * @param integer $responserequired 0 or 1 depending on if the response is required or not.
     * @param integer $attachmentsrequired Number or attachments required; -1 is unlimited.
     * @param integer $filesattached Number of files attached.
     * @return void
     */
    public function test_summarise_response_text_attachments(int $responserequired, int $attachmentsrequired, int $filesattached): void {
        $this->resetAfterTest();

        // Create sample attachments.
        $attachments = $this->create_user_and_sample_attachments($filesattached);

        // Create the essay question under test.
        $essay = test_question_maker::make_an_essay_question();
        $essay->start_attempt(new question_attempt_step(), 1);

        $essay->responserequired = $responserequired;
        $essay->attachmentsrequired = $attachmentsrequired;
        $essay->responseformat = 'editor';

        $textanswer = '';
        $expected = '';
        if ($responserequired) {
            $textanswer = 'This is the text input for my essay.';
            $expected .= $textanswer;
        }
        if ($filesattached) {
            $expected .= 'Attachments:';
            for ($i = 0; $i < $filesattached; $i++) {
                if ($i > 0) {
                    $expected .= ',';
                }
                $expected .= " $i (1 bytes)";
                $result = $essay->summarise_response(
                    ['answer' => $textanswer, 'answerformat' => FORMAT_HTML, 'attachments' => $attachments[$i + 1]]
                );
                $this->assertEquals($expected, $result);
            }
        }
    }

    /**
     * Data provider for test_summarise_response_text_attachments().
     *
     * @return array
     */
    public function summarise_response_text_attachments_provider(): array {
        return [
            'Text required, 1 attachments required' => [
                'responserequired' => 1,
                'attachmentsrequired' => 1,
                'filesattached' => 4,
            ],
            'Text not required, 4 attachments required' => [
                'responserequired' => 0,
                'attachmentsrequired' => 4,
                'filesattached' => 4,
            ],
            'Text not required, 4 attachments required' => [
                'responserequired' => 0,
                'attachmentsrequired' => -1,
                'filesattached' => 2,
            ],
        ];
    }