diff --git a/src/Renderer/SimplePhpRenderer.php b/src/Renderer/SimplePhpRenderer.php
index 5337b571010f7acad7469f7fce7c616a26a795f9..9d05084e69624437d6015c02f780885a4b225a00 100644
--- a/src/Renderer/SimplePhpRenderer.php
+++ b/src/Renderer/SimplePhpRenderer.php
@@ -29,7 +29,7 @@ class SimplePhpRenderer implements Renderer
 
     /**
      * @param string $template
-     * @param array $params
+     * @param array|null $params
      *
      * @return string
      */
@@ -40,7 +40,7 @@ class SimplePhpRenderer implements Renderer
         }
 
         ob_start();
-        include($this->resolver->resolve($template));
+        include($this->resolver->resolve($template . '.php'));
 
         return ob_get_clean();
     }
diff --git a/src/Resolver/DirResolver.php b/src/Resolver/DirResolver.php
index 5122631eb9b78ec3a32efc900a1e4468acd294bd..69f1b6cca966ae5b396327152baf40d690ed48df 100644
--- a/src/Resolver/DirResolver.php
+++ b/src/Resolver/DirResolver.php
@@ -39,7 +39,7 @@ class DirResolver implements Resolver
     public function resolve($name, Renderer $renderer = null)
     {
         $dir = rtrim($this->dir, '/');
-        $fullName = $dir . '/' . $name . '.php';
+        $fullName = $dir . '/' . $name;
         if (file_exists($fullName)) {
             return $fullName;
         }
diff --git a/src/Resolver/WPThemeResolver.php b/src/Resolver/WPThemeResolver.php
index 68d9a5715f9f502dc73b449647d81fda2b69e245..d95028ca24e72f3f63717c6a1f01d03a27116110 100644
--- a/src/Resolver/WPThemeResolver.php
+++ b/src/Resolver/WPThemeResolver.php
@@ -40,7 +40,7 @@ class WPThemeResolver implements Resolver
     {
         $templateFile = locate_template(
             [
-                trailingslashit($this->template_base_path) . $name . '.php',
+                trailingslashit($this->template_base_path) . $name,
             ]
         );
         if ( ! $templateFile) {
diff --git a/tests/unit/Resolver/TestChainResolver.php b/tests/unit/Resolver/TestChainResolver.php
index 22f56cb2297bdc88ce56d3fc1d778cbf748d5d35..3d5d51011d3764141325aabea78a63778f635794 100644
--- a/tests/unit/Resolver/TestChainResolver.php
+++ b/tests/unit/Resolver/TestChainResolver.php
@@ -28,7 +28,7 @@ class TestChainResolver extends \PHPUnit\Framework\TestCase
             ->andReturn(self::RESPONSE_OF_RESOLVER);
 
         $resolver = new ChainResolver(new NullResolver(), new NullResolver(), $validResolver);
-        $this->assertEquals(self::RESPONSE_OF_RESOLVER, $resolver->resolve('whatever'));
+        $this->assertEquals(self::RESPONSE_OF_RESOLVER, $resolver->resolve('whatever.php'));
     }
 
     public function testUseFirstResolverFirst()
@@ -39,7 +39,7 @@ class TestChainResolver extends \PHPUnit\Framework\TestCase
             ->andReturn(self::RESPONSE_OF_RESOLVER);
 
         $resolver = new ChainResolver($validResolver, new NullResolver(), new NullResolver());
-        $this->assertEquals(self::RESPONSE_OF_RESOLVER, $resolver->resolve('whatever'));
+        $this->assertEquals(self::RESPONSE_OF_RESOLVER, $resolver->resolve('whatever.php'));
     }
 
     public function testThrowExceptionWhenBothCannotFind()
diff --git a/tests/unit/Resolver/TestDirResolver.php b/tests/unit/Resolver/TestDirResolver.php
index 04c4483ac6201934f45b871fe47fcb5c59d58591..7c9876099f9b66247fc9d209febff09f26a5ff61 100644
--- a/tests/unit/Resolver/TestDirResolver.php
+++ b/tests/unit/Resolver/TestDirResolver.php
@@ -5,7 +5,7 @@ use WPDesk\View\Resolver\Exception\CanNotResolve;
 
 class TestDirResolver extends \PHPUnit\Framework\TestCase
 {
-    const TEMPLATE_NAME = 'some_template';
+    const TEMPLATE_NAME = 'some_template.php';
     const TEMPLATE_FILE = 'some_template.php';
     const TEMPLATE_SUBDIR = 'templates';
 
diff --git a/tests/unit/Resolver/TestWpThemeResolver.php b/tests/unit/Resolver/TestWpThemeResolver.php
index af7a08bfaf65444c564d4ebfe19e03fdee7e3f5b..ddcc43c5210c459d0024da728b63a0257ac2b6cd 100644
--- a/tests/unit/Resolver/TestWpThemeResolver.php
+++ b/tests/unit/Resolver/TestWpThemeResolver.php
@@ -5,7 +5,7 @@ use WPDesk\View\Resolver\Exception\CanNotResolve;
 
 class TestThemeResolver extends \PHPUnit\Framework\TestCase
 {
-    const TEMPLATE_NAME = 'some_template';
+    const TEMPLATE_NAME = 'some_template.php';
     const TEMPLATE_FILE = 'some_template.php';
     const TEMPLATE_SUBDIR = 'templates';