Define expected behaviour with elife assessment class with tests

elifesciences/issues#9034

src/Model/ElifeAssessment.php

@@ -11,19 +11,25 @@ final class ElifeAssessment implements Model
      * @internal
      */
     public function __construct(
-        array $significance,
-        array $strength
+        array $significance = null,
+        array $strength = null
     ) {
         $this->significance = $significance;
         $this->strength = $strength;
     }
 
-    public function getSignificance() : array
+    /**
+     * @return array|null
+     */
+    public function getSignificance()
     {
         return $this->significance;
     }
 
-    public function getStrength() : array
+    /**
+     * @return array|null
+     */
+    public function getStrength()
     {
         return $this->strength;
     }

test/Model/ElifeAssessmentTest.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace test\eLife\ApiSdk\Model\Block;
+
+use eLife\ApiSdk\Model\ElifeAssessment;
+use PHPUnit\Framework\TestCase;
+
+final class ElifeAssessmentTest extends TestCase
+{
+
+    /**
+     * @test
+     */
+    public function it_may_have_significance_terms()
+    {
+        $with = new ElifeAssessment(['important'], ['solid']);
+        $withOut = new ElifeAssessment(null, ['solid']);
+
+        $this->assertSame(['important'], $with->getSignificance());
+        $this->assertNull($withOut->getSignificance());
+    }
+
+    /**
+     * @test
+     */
+    public function it_may_have_strength_terms()
+    {
+        $with = new ElifeAssessment(['important'], ['solid']);
+        $withOut = new ElifeAssessment(['important']);
+
+        $this->assertSame(['solid'], $with->getStrength());
+        $this->assertNull($withOut->getStrength());
+    }
+}