fix(navigation): Allow apps to hide registered navigation closure entries

Signed-off-by: Joas Schilling <coding@schilljs.com>

Author: nickvergessen

lib/private/NavigationManager.php

@@ -57,7 +57,7 @@ class NavigationManager implements INavigationManager {
 	protected ?string $activeEntry = null;
 	/** @var array<string, NavigationEntryOutput> */
 	protected array $entries = [];
-	/** @var list<callable(): NavigationEntry> */
+	/** @var list<callable(): ?NavigationEntry> */
 	protected array $closureEntries = [];
 	/** User defined app order (cached for the `add` function) */
 	protected ?array $customAppOrder = null;
@@ -357,7 +357,12 @@ private function resolveAppNavigationEntries(): void {
 			// as apps might add new navigation entries via closures at any time
 			while ($c = array_pop($this->closureEntries)) {
 				try {
-					$this->add($c());
+					$entry = $c();
+					if ($entry === null) {
+						$this->logger->debug('Closure of navigation entry returned null, skipping');
+						continue;
+					}
+					$this->add($entry);
 				} catch (\Throwable $e) {
 					$this->logger->error('Failed to add navigation entry from closure', ['exception' => $e]);
 				}

lib/public/INavigationManager.php

@@ -80,7 +80,7 @@ interface INavigationManager {
 	/**
 	 * Creates a new navigation entry
 	 *
-	 * @param NavigationEntry|callable():NavigationEntry $entry If a menu entry (type = 'link') is added, you shall also set app to the app that
+	 * @param NavigationEntry|callable():?NavigationEntry $entry If a menu entry (type = 'link') is added, you shall also set app to the app that
 	 *                                                          added the entry. The use of a closure is preferred, because it will avoid loading
 	 *                                                          the routing of your app, unless required.
 	 * @return void