From 131daf401e63ee35bebd65fea118069bb138a4b1 Mon Sep 17 00:00:00 2001
From: Andrey Pyzhikov <5071@mail.ru>
Date: Thu, 29 Apr 2021 18:46:21 +0800
Subject: [PATCH] Fix: Nested sections rendering

---
 system/View/View.php                       | 30 +++++++++++++---------
 tests/system/View/ViewTest.php             | 15 ++++++++++-
 tests/system/View/Views/nested_section.php | 14 ++++++++++
 3 files changed, 46 insertions(+), 13 deletions(-)
 create mode 100644 tests/system/View/Views/nested_section.php

diff --git a/system/View/View.php b/system/View/View.php
index 935729393626..9bc3367d2c42 100644
--- a/system/View/View.php
+++ b/system/View/View.php
@@ -120,9 +120,9 @@ class View implements RendererInterface
 	 * The name of the current section being rendered,
 	 * if any.
 	 *
-	 * @var string|null
+	 * @var array<string>
 	 */
-	protected $currentSection;
+	protected $sectionStack = [];
 
 	/**
 	 * Constructor
@@ -227,7 +227,7 @@ public function render(string $view, array $options = null, bool $saveData = nul
 		// When using layouts, the data has already been stored
 		// in $this->sections, and no other valid output
 		// is allowed in $output so we'll overwrite it.
-		if (! is_null($this->layout) && empty($this->currentSection))
+		if (! is_null($this->layout) && $this->sectionStack === [])
 		{
 			$layoutView   = $this->layout;
 			$this->layout = null;
@@ -402,35 +402,41 @@ public function extend(string $layout)
 	/**
 	 * Starts holds content for a section within the layout.
 	 *
-	 * @param string $name
+	 * @param string $name Section name
+	 *
+	 * @return void
 	 */
-	public function section(string $name)
+	public function section(string $name): void
 	{
-		$this->currentSection = $name;
+		$this->sectionStack[] = $name;
 
 		ob_start();
 	}
 
 	/**
+	 * Captures the last section
+	 *
+	 * @return void
 	 * @throws RuntimeException
 	 */
-	public function endSection()
+	public function endSection(): void
 	{
 		$contents = ob_get_clean();
 
-		if (empty($this->currentSection))
+		if ($this->sectionStack === [])
 		{
 			throw new RuntimeException('View themes, no current section.');
 		}
 
+		$section = array_pop($this->sectionStack);
+
 		// Ensure an array exists so we can store multiple entries for this.
-		if (! array_key_exists($this->currentSection, $this->sections))
+		if (! array_key_exists($section, $this->sections))
 		{
-			$this->sections[$this->currentSection] = [];
+			$this->sections[$section] = [];
 		}
-		$this->sections[$this->currentSection][] = $contents;
 
-		$this->currentSection = null;
+		$this->sections[$section][] = $contents;
 	}
 
 	/**
diff --git a/tests/system/View/ViewTest.php b/tests/system/View/ViewTest.php
index 8dd1d4431a38..7d2cf84becbb 100644
--- a/tests/system/View/ViewTest.php
+++ b/tests/system/View/ViewTest.php
@@ -367,7 +367,7 @@ public function testRenderSaveDataCover()
 		$this->assertEquals(true, $this->getPrivateProperty($view, 'saveData'));
 	}
 
-	public function testRenderSaveDataUseAflterSaveDataFalse()
+	public function testRenderSaveDataUseAfterSaveDataFalse()
 	{
 		$view = new View($this->config, $this->viewsDir, $this->loader);
 		$view->setVar('testString', 'test');
@@ -387,4 +387,17 @@ public function testCachedAutoDiscoverAndRender()
 		// this second renderings should go thru the cache
 		$this->assertStringContainsString($expected, $view->render('Nested/simple', ['cache' => 10]));
 	}
+
+	public function testRenderNestedSections()
+	{
+		$view = new View($this->config, $this->viewsDir, $this->loader);
+
+		$view->setVar('testString', 'Hello World');
+
+		$content = $view->render('nested_section');
+
+		$this->assertStringContainsString('<p>First</p>', $content);
+		$this->assertStringContainsString('<p>Second</p>', $content);
+		$this->assertStringContainsString('<p>Third</p>', $content);
+	}
 }
diff --git a/tests/system/View/Views/nested_section.php b/tests/system/View/Views/nested_section.php
new file mode 100644
index 000000000000..a89e6234ec5c
--- /dev/null
+++ b/tests/system/View/Views/nested_section.php
@@ -0,0 +1,14 @@
+<?php $this->extend('layout'); ?>
+
+<?php $this->section('content'); ?>
+<p>Second</p>
+
+    <?php $this->section('content'); ?>
+    <p>First</p>
+    <?php $this->endSection(); ?>
+
+<?php $this->endSection(); ?>
+
+<?php $this->section('content'); ?>
+<p>Third</p>
+<?php $this->endSection(); ?>