Fix error on WebView::renderAjax with path relative to basePath e.g. …

…"//layouts/main" (#139)

src/Event/ViewEvent.php

@@ -10,21 +10,22 @@
 abstract class ViewEvent
 {
     /**
-     * @var string the view file being rendered.
+     * @var string|null The view file being rendered. `null` if no view file is being rendered.
      */
-    private string $file;
+    private ?string $file;
+
     /**
      * @var array the parameter array passed to the {@see View::render()} method.
      */
     private array $parameters;
 
-    public function __construct(string $file, array $parameters = [])
+    public function __construct(?string $file, array $parameters = [])
     {
         $this->file = $file;
         $this->parameters = $parameters;
     }
 
-    public function file(): string
+    public function file(): ?string
     {
         return $this->file;
     }

src/View.php

@@ -299,7 +299,7 @@ protected function findTemplateFile(string $view): string
         if (strncmp($view, '//', 2) === 0) {
             // path relative to basePath e.g. "//layouts/main"
             $file = $this->basePath . '/' . ltrim($view, '/');
-        } elseif (($currentViewFile = $this->getRequestedViewFile()) !== false) {
+        } elseif (($currentViewFile = $this->getRequestedViewFile()) !== null) {
             // path relative to currently rendered view
             $file = dirname($currentViewFile) . '/' . $view;
         } elseif ($this->context instanceof ViewContextInterface) {
@@ -419,19 +419,19 @@ public function localize(string $file, ?string $language = null, ?string $source
     }
 
     /**
-     * @return bool|string the view file currently being rendered. False if no view file is being rendered.
+     * @return string|null The view file currently being rendered. `null` if no view file is being rendered.
      */
-    public function getViewFile()
+    public function getViewFile(): ?string
     {
-        return empty($this->viewFiles) ? false : end($this->viewFiles)['resolved'];
+        return empty($this->viewFiles) ? null : end($this->viewFiles)['resolved'];
     }
 
     /**
-     * @return bool|string the requested view currently being rendered. False if no view file is being rendered.
+     * @return string|null The requested view currently being rendered. `null` if no view file is being rendered.
      */
-    protected function getRequestedViewFile()
+    protected function getRequestedViewFile(): ?string
     {
-        return empty($this->viewFiles) ? false : end($this->viewFiles)['requested'];
+        return empty($this->viewFiles) ? null : end($this->viewFiles)['requested'];
     }
 
     /**

tests/WebViewTest.php

@@ -98,4 +98,13 @@ public function testRegisterCss(): void
         $html = $this->webView->renderFile($this->layoutPath, ['content' => '']);
         $this->assertStringContainsString('<style id="mainCss">.red{color:red;}</style></head>', $html);
     }
+
+    public function testRenderAjaxWithoutContext(): void
+    {
+        $content = 'Hello!';
+
+        $html = $this->webView->renderAjax('//only-content.php', ['content' => $content]);
+
+        $this->assertSame($content, $html);
+    }
 }

tests/public/view/only-content.php

@@ -0,0 +1,7 @@
+<?php
+/**
+ * @var $this \Yiisoft\View\WebView
+ * @var $content string;
+ */
+
+echo $content;