Refactor PreloadBuilderTest and add new test

Refactored test method name in PreloadBuilderTest for clarity. Added new test `testPreloaderWithCompiling` to cover more cases, primarily for PreloadBuilder with opcache compiler enabled. Check for specific function existence in compiled contents.

tests/Tools/PreloadBuilderTest.php

@@ -19,11 +19,12 @@
 use JBZoo\CsvBlueprint\Tools\PreloadBuilder;
 use JBZoo\PHPUnit\TestCase;
 
+use function JBZoo\PHPUnit\isContain;
 use function JBZoo\PHPUnit\isNotContain;
 
 class PreloadBuilderTest extends TestCase
 {
-    public function testPreloader(): void
+    public function testPreloaderWithoutCompiling(): void
     {
         (new PreloadBuilder(enableOpcacheCompiler: false))
             ->setExcludes([
@@ -36,5 +37,30 @@ public function testPreloader(): void
 
         $content = \file_get_contents(PROJECT_BUILD . '/preload.php');
         isNotContain(__FILE__, $content);
+        isContain('PreloadBuilder.php', $content);
+
+        isNotContain('function_exists', $content);
+        isNotContain('opcache_compile_file', $content);
+        isContain('require_once', $content);
+    }
+
+    public function testPreloaderWithCompiling(): void
+    {
+        (new PreloadBuilder(enableOpcacheCompiler: true))
+            ->setExcludes([
+                __FILE__,
+            ])
+            ->setFiles(\get_included_files())
+            ->saveToFile(PROJECT_BUILD . '/preload.php');
+
+        self::assertFileExists(PROJECT_BUILD . '/preload.php');
+
+        $content = \file_get_contents(PROJECT_BUILD . '/preload.php');
+        isNotContain(__FILE__, $content);
+        isContain('PreloadBuilder.php', $content);
+
+        isContain('function_exists', $content);
+        isContain('opcache_compile_file', $content);
+        isNotContain('require_once', $content);
     }
 }