PHPStan level 5 (#4110)

* Fix most PHPDocs errors
Contributes to https://github.com/FreshRSS/FreshRSS/issues/4103
https://phpstan.org/writing-php-code/phpdoc-types

* Avoid func_get_args
Use variadic syntax instead https://php.net/manual/functions.arguments#functions.variable-arg-list
And avoid dynamic functions names when possible to more easily identify calls and unused functions.
Contributes to https://github.com/FreshRSS/FreshRSS/issues/4103

* PHPStan level 3

* PHPStand level 4

* Update default to PHPStan level 4

* Towards level 5

* Fix level 4 regression

* Towards level 5

* Pass PHPStan level 5

* Towards level 6

* Remove erronenous regression from changelog
https://github.com/FreshRSS/FreshRSS/pull/4116

2 files changed, 27 insertions, 11 deletions

diff --git a/p/api/fever.php b/p/api/fever.php
index 684e851a6..6a7f10668 100644
--- a/p/api/fever.php
+++ b/p/api/fever.php
@@ -30,6 +30,9 @@ Minz_Session::init('FreshRSS', true);
 // <Debug>
 $ORIGINAL_INPUT = file_get_contents('php://input', false, null, 0, 1048576);
 
+/**
+ * @return string
+ */
 function debugInfo() {
 	if (function_exists('getallheaders')) {
 		$ALL_HEADERS = getallheaders();
@@ -503,18 +506,12 @@ class FeverAPI
 
 		if (isset($_REQUEST['max_id'])) {
 			// use the max_id argument to request the previous $item_limit items
-			$max_id = '' . $_REQUEST['max_id'];
-			if (!ctype_digit($max_id)) {
-				$max_id = null;
-			}
+			$max_id = ctype_digit('' . $_REQUEST['max_id']) ? intval($_REQUEST['max_id']) : null;
 		} elseif (isset($_REQUEST['with_ids'])) {
 			$entry_ids = explode(',', $_REQUEST['with_ids']);
 		} elseif (isset($_REQUEST['since_id'])) {
 			// use the since_id argument to request the next $item_limit items
-			$since_id = '' . $_REQUEST['since_id'];
-			if (!ctype_digit($since_id)) {
-				$since_id = null;
-			}
+			$since_id = ctype_digit('' . $_REQUEST['since_id']) ? intval($_REQUEST['since_id']) : null;
 		}
 
 		$items = array();
diff --git a/p/api/greader.php b/p/api/greader.php
index 33373293d..d233fd957 100644
--- a/p/api/greader.php
+++ b/p/api/greader.php
@@ -29,20 +29,36 @@ require(LIB_PATH . '/lib_rss.php');	//Includes class autoloader
 $ORIGINAL_INPUT = file_get_contents('php://input', false, null, 0, 1048576);
 
 if (PHP_INT_SIZE < 8) {	//32-bit
+	/**
+	 * @param string|int $dec
+	 * @return string
+	 */
 	function dec2hex($dec) {
 		return str_pad(gmp_strval(gmp_init($dec, 10), 16), 16, '0', STR_PAD_LEFT);
 	}
+	/**
+	 * @param string $hex
+	 * @return string
+	 */
 	function hex2dec($hex) {
-		if (!ctype_xdigit($hex)) return 0;
+		if (!ctype_xdigit($hex)) return '0';
 		return gmp_strval(gmp_init($hex, 16), 10);
 	}
 } else {	//64-bit
+	/**
+	 * @param string|int $dec
+	 * @return string
+	 */
 	function dec2hex($dec) {	//http://code.google.com/p/google-reader-api/wiki/ItemId
 		return str_pad(dechex($dec), 16, '0', STR_PAD_LEFT);
 	}
+	/**
+	 * @param string $hex
+	 * @return string
+	 */
 	function hex2dec($hex) {
-		if (!ctype_xdigit($hex)) return 0;
-		return hexdec($hex);
+		if (!ctype_xdigit($hex)) return '0';
+		return '' . hexdec($hex);
 	}
 }
 
@@ -79,6 +95,9 @@ function multiplePosts($name) {	//https://bugs.php.net/bug.php?id=51633
 	return $result;
 }
 
+/**
+ * @return string
+ */
 function debugInfo() {
 	if (function_exists('getallheaders')) {
 		$ALL_HEADERS = getallheaders();