Add documentation test for query prefix

Author: MacFJA

src/Query/Builder/Prefix.php

@@ -21,8 +21,7 @@
 
 namespace MacFJA\RediSearch\Query\Builder;
 
-use function call_user_func;
-use function is_callable;
+use MacFJA\RediSearch\Query\Escaper;
 
 class Prefix implements QueryElement
 {
@@ -36,11 +35,7 @@ public function __construct(string $prefix)
 
     public function render(?callable $escaper = null): string
     {
-        if (is_callable($escaper)) {
-            return call_user_func($escaper, $this->prefix).'*';
-        }
-
-        return $this->prefix.'*';
+        return Escaper::escapeWord($this->prefix).'*';
     }
 
     public function priority(): int

tests/Query/BuilderTest.php

@@ -192,6 +192,22 @@ public function testDocGeoExample1(): void
         ));
     }
 
+    /**
+     * @see https://oss.redis.com/redisearch/Query_Syntax/#prefix_matching
+     */
+    public function testDocPrefixExample1(): void
+    {
+        $expected = 'hel* world';
+        $builder = new Builder();
+
+        $builder
+            ->addElement(new Builder\Prefix('hel'))
+            ->addString('world')
+        ;
+
+        static::assertSame($expected, $builder->render());
+    }
+
     /**
      * @see https://oss.redislabs.com/redisearch/Query_Syntax/#fuzzy_matching
      */