Fix app version to be always string and neither array nor null

Signed-off-by: Morris Jobke <hey@morrisjobke.de>

lib/private/App/AppManager.php

@@ -380,10 +380,10 @@ class AppManager implements IAppManager {
 		return $data;
 	}
 
-	public function getAppVersion(string $appId, bool $useCache = true) {
+	public function getAppVersion(string $appId, bool $useCache = true): string {
 		if(!$useCache || !isset($this->appVersions[$appId])) {
 			$appInfo = \OC::$server->getAppManager()->getAppInfo($appId);
-			$this->appVersions[$appId] = ($appInfo !== null) ? $appInfo['version'] : '0';
+			$this->appVersions[$appId] = ($appInfo !== null && isset($appInfo['version'])) ? $appInfo['version'] : '0';
 		}
 		return $this->appVersions[$appId];
 	}

lib/private/Installer.php

@@ -112,7 +112,7 @@ class Installer {
 			);
 		}
 
-		$version = \OCP\Util::getVersion();
+		$version = implode('.', \OCP\Util::getVersion());
 		if (!\OC_App::isAppCompatible($version, $info)) {
 			throw new \Exception(
 				// TODO $l

lib/private/legacy/app.php

@@ -856,7 +856,7 @@ class OC_App {
 	 *
 	 * @return boolean true if compatible, otherwise false
 	 */
-	public static function isAppCompatible($ocVersion, $appInfo) {
+	public static function isAppCompatible(string $ocVersion, array $appInfo): bool {
 		$requireMin = '';
 		$requireMax = '';
 		if (isset($appInfo['dependencies']['nextcloud']['@attributes']['min-version'])) {
@@ -877,10 +877,6 @@ class OC_App {
 			$requireMax = $appInfo['requiremax'];
 		}
 
-		if (is_array($ocVersion)) {
-			$ocVersion = implode('.', $ocVersion);
-		}
-
 		if (!empty($requireMin)
 			&& version_compare(self::adjustVersionParts($ocVersion, $requireMin), $requireMin, '<')
 		) {

lib/public/App/IAppManager.php

@@ -51,10 +51,10 @@ interface IAppManager {
 	 *
 	 * @param string $appId
 	 * @param bool $useCache
-	 * @return mixed
+	 * @return string
 	 * @since 14.0.0
 	 */
-	public function getAppVersion(string $appId, bool $useCache = true);
+	public function getAppVersion(string $appId, bool $useCache = true): string;
 
 	/**
 	 * Check if an app is enabled for user

tests/lib/AppTest.php

@@ -309,19 +309,6 @@ class AppTest extends \Test\TestCase {
 		$this->assertEquals($expectedResult, \OC_App::isAppCompatible($ocVersion, $appInfo));
 	}
 
-	/**
-	 * Test that the isAppCompatible method also supports passing an array
-	 * as $ocVersion
-	 */
-	public function testIsAppCompatibleWithArray() {
-		$ocVersion = array(6);
-		$appInfo = array(
-			'requiremin' => '6',
-			'requiremax' => '6',
-		);
-		$this->assertTrue(\OC_App::isAppCompatible($ocVersion, $appInfo));
-	}
-
 	/**
 	 * Tests that the app order is correct
 	 */