feat: decide when a conditional questionnaire question is shown

tests/Model/Questionnaire/DefinitionTest.php

@@ -0,0 +1,70 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Model\Questionnaire;
+
+use App\Enum\ConditionOperator;
+use App\Enum\QuestionType;
+use App\Model\Questionnaire\Condition;
+use App\Model\Questionnaire\Definition;
+use App\Model\Questionnaire\Option;
+use App\Model\Questionnaire\Question;
+use App\Model\Questionnaire\Section;
+use PHPUnit\Framework\TestCase;
+
+class DefinitionTest extends TestCase
+{
+    public function testQuestionWithoutConditionIsAlwaysVisible(): void
+    {
+        $definition = $this->definition();
+
+        $this->assertTrue($definition->isVisible($definition->getQuestion('damage'), []));
+    }
+
+    public function testFollowUpIsVisibleOnlyForItsAnswer(): void
+    {
+        $definition = $this->definition();
+        $followUp = $definition->getQuestion('claim');
+
+        $this->assertTrue($definition->isVisible($followUp, ['damage' => 'yes']));
+        $this->assertFalse($definition->isVisible($followUp, ['damage' => 'no']));
+    }
+
+    /**
+     * "details" depends on "claim", which depends on "damage". Switching "damage" to "no" hides
+     * "claim"; its stale answer must not keep "details" open.
+     */
+    public function testFollowUpOfAHiddenQuestionIsHidden(): void
+    {
+        $definition = $this->definition();
+        $details = $definition->getQuestion('details');
+
+        $this->assertTrue($definition->isVisible($details, ['damage' => 'yes', 'claim' => 'expected']));
+        $this->assertFalse($definition->isVisible($details, ['damage' => 'no', 'claim' => 'expected']));
+    }
+
+    private function definition(): Definition
+    {
+        $yesNo = [new Option('yes', 'Ja'), new Option('no', 'Nein')];
+
+        return new Definition('sample', 1, 'Beispiel', null, [
+            new Section('main', null, [
+                new Question('damage', 'Schäden?', QuestionType::CHOICE, options: $yesNo),
+                new Question(
+                    'claim',
+                    'Kommt noch was?',
+                    QuestionType::CHOICE,
+                    options: [new Option('expected', 'Ja'), new Option('settled', 'Nein')],
+                    showIf: new Condition('damage', ConditionOperator::EQUALS, 'yes'),
+                ),
+                new Question(
+                    'details',
+                    'Was ist passiert?',
+                    QuestionType::TEXTAREA,
+                    showIf: new Condition('claim', ConditionOperator::EQUALS, 'expected'),
+                ),
+            ]),
+        ]);
+    }
+}