[BUGFIX] Handle float values in options facet parser

Ports: TYPO3-Solr#3722 by @saschanowak

Classes/Domain/Search/ResultSet/Facets/OptionBased/Options/OptionsFacetParser.php

@@ -133,7 +133,7 @@ protected function getOptionsFromSolrResponse(string $facetName, ResponseAdapter
         foreach ($response->facets->{$facetName}->buckets as $bucket) {
             $optionValue = $bucket->val;
             $optionCount = $bucket->count;
-            $optionsFromSolrResponse[$optionValue] = $optionCount;
+            $optionsFromSolrResponse[(string)$optionValue] = $optionCount;
         }
 
         return $optionsFromSolrResponse;

Tests/Unit/Domain/Search/ResultSet/Facets/OptionBased/Options/OptionsFacetParserTest.php

@@ -0,0 +1,58 @@
+<?php
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace ApacheSolrForTypo3\Solr\Tests\Unit\Domain\Search\ResultSet\Facets\OptionBased\Options;
+
+use ApacheSolrForTypo3\Solr\Domain\Search\ResultSet\Facets\OptionBased\Options\OptionsFacetParser;
+use ApacheSolrForTypo3\Solr\System\Solr\ResponseAdapter;
+use ApacheSolrForTypo3\Solr\Tests\Unit\UnitTest;
+
+class OptionsFacetParserTest extends UnitTest
+{
+    /**
+     * @test
+     */
+    public function canListFloatValuesAsOptionsFromSolrResponse(): void
+    {
+        $responseAdapter = new ResponseAdapter(
+            /* @lang JSON */
+            '{
+              "facets": {
+                "floatOptions": {
+                  "buckets": [
+                    { "val": 0.001, "count": 1 },
+                    { "val": 0.002, "count": 2 },
+                    { "val": 0.003, "count": 3 }
+                  ]
+                }
+              }
+            }'
+        );
+        $optionsFacetParser = $this->getAccessibleMock(
+            OptionsFacetParser::class,
+            null,
+            [],
+            '',
+            false
+        );
+        /** @link OptionsFacetParser::getOptionsFromSolrResponse */
+        $optionsArray = $optionsFacetParser->_call(
+            'getOptionsFromSolrResponse',
+            'floatOptions',
+            $responseAdapter,
+        );
+        self::assertCount(3, $optionsArray, 'EXT:solr can not list floats in facets.');
+    }
+}