feature: throw exception if header/footer and partials used at same time

closes #288

Author: g105b

src/Dispatch/Dispatcher.php

@@ -403,6 +403,7 @@ public function processResponse(
 
 		$componentList = $this->viewModelProcessor?->processPartialContent(
 			$this->viewModel,
+			$this->viewAssembly,
 		);
 
 // TODO: CSRF handling - needs to be done on any POST request.

src/Logic/HTMLDocumentProcessor.php

@@ -8,6 +8,7 @@
 use GT\DomTemplate\PartialExpander;
 use GT\Routing\Assembly;
 use GT\Routing\Path\DynamicPath;
+use GT\WebEngine\View\HeaderFooterPartialConflictException;
 
 class HTMLDocumentProcessor extends ViewModelProcessor {
 	function processDynamicPath(
@@ -30,7 +31,16 @@ function processDynamicPath(
 
 	function processPartialContent(
 		HTMLDocument $model,
+		?Assembly $viewAssembly = null,
 	):LogicAssemblyComponentList {
+		if($viewAssembly
+		&& $this->containsPartialExtends($model)
+		&& $this->containsHeaderOrFooterView($viewAssembly)) {
+			throw new HeaderFooterPartialConflictException(
+				"Header/footer view files cannot be combined with partial views."
+			);
+		}
+
 		$componentList = new LogicAssemblyComponentList();
 
 		try {
@@ -81,4 +91,54 @@ function processPartialContent(
 
 		return $componentList;
 	}
+
+	private function containsHeaderOrFooterView(Assembly $viewAssembly):bool {
+		foreach($viewAssembly as $viewFile) {
+			$fileName = pathinfo($viewFile, PATHINFO_FILENAME);
+			if($fileName === "_header" || $fileName === "_footer") {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	private function containsPartialExtends(HTMLDocument $model):bool {
+		return $this->containsPartialExtendsInNode($model->documentElement);
+	}
+
+	/** @return ?array<string, array<string, string>|string> */
+	private function parseCommentIni(string $data):?array {
+		set_error_handler(
+			static fn() => true
+		);
+
+		try {
+			$parsed = parse_ini_string($data, true);
+		}
+		finally {
+			restore_error_handler();
+		}
+
+		return is_array($parsed)
+			? $parsed
+			: null;
+	}
+
+	private function containsPartialExtendsInNode(\DOMNode $node):bool {
+		if($node->nodeType === XML_COMMENT_NODE) {
+			$parsed = $this->parseCommentIni(trim($node->textContent));
+			if(isset($parsed["extends"])) {
+				return true;
+			}
+		}
+
+		foreach($node->childNodes as $childNode) {
+			if($this->containsPartialExtendsInNode($childNode)) {
+				return true;
+			}
+		}
+
+		return false;
+	}
 }

src/Logic/ViewModelProcessor.php

@@ -1,8 +1,8 @@
 <?php
 namespace GT\WebEngine\Logic;
 
-use Generator;
 use GT\Dom\HTMLDocument;
+use GT\Routing\Assembly;
 use GT\Routing\Path\DynamicPath;
 
 abstract class ViewModelProcessor {
@@ -18,5 +18,6 @@ abstract function processDynamicPath(
 
 	abstract function processPartialContent(
 		HTMLDocument $model,
+		?Assembly $viewAssembly = null,
 	):LogicAssemblyComponentList;
 }

src/View/HeaderFooterPartialConflictException.php

@@ -0,0 +1,6 @@
+<?php
+namespace GT\WebEngine\View;
+
+use GT\WebEngine\WebEngineException;
+
+class HeaderFooterPartialConflictException extends WebEngineException {}

test/phpunit/DefaultRouterTest.php

@@ -13,6 +13,7 @@
 use GT\Routing\RouterConfig;
 use GT\WebEngine\DefaultRouter;
 use Gt\ServiceContainer\Container;
+use GT\WebEngine\View\HeaderFooterPartialConflictException;
 use GT\WebEngine\View\HTMLView;
 use PHPUnit\Framework\TestCase;
 
@@ -109,11 +110,11 @@ class_exists(PartialExpander::class);
 		$viewModel = $view->createViewModel();
 
 		$processor = new HTMLDocumentProcessor("components", "page/_partial");
-		$this->expectException(\LogicException::class);
+		$this->expectException(HeaderFooterPartialConflictException::class);
 		$this->expectExceptionMessage(
 			"Header/footer view files cannot be combined with partial views."
 		);
-		$processor->processPartialContent($viewModel);
+		$processor->processPartialContent($viewModel, $sut->getViewAssembly());
 	}
 
 	private function removeDirectory(string $dir):void {