[TASK] Add native type declarations for RuleSet (#1186)

Part of #811

Author: oliverklee

CHANGELOG.md

@@ -34,7 +34,7 @@ Please also have a look at our
 - Use more native type declarations and strict mode
   (#641, #772, #774, #778, #804, #841, #873, #875, #891, #922, #923, #933, #958,
   #964, #967, #1000, #1044, #1134, #1136, #1137, #1139, #1140, #1141, #1145,
-  #1162, #1163, #1166, #1172, #1174, #1178, #1179, #1181, #1183, #1184)
+  #1162, #1163, #1166, #1172, #1174, #1178, #1179, #1181, #1183, #1184, #1186)
 - Add visibility to all class/interface constants (#469)
 
 ### Deprecated

src/RuleSet/RuleSet.php

@@ -151,14 +151,13 @@ public function addRule(Rule $ruleToAdd, ?Rule $sibling = null): void
      *        as well as one matching the pattern with the dash excluded.
      *        Passing a `Rule` behaves like calling `getRules($rule->getRule())`.
      *
-     * @return array<int, Rule>
+     * @return array<int<0, max>, Rule>
      */
-    public function getRules($searchPattern = null)
+    public function getRules($searchPattern = null): array
     {
         if ($searchPattern instanceof Rule) {
             $searchPattern = $searchPattern->getRule();
         }
-        /** @var array<int, Rule> $result */
         $result = [];
         foreach ($this->rules as $propertyName => $rules) {
             // Either no search rule is given or the search rule matches the found rule exactly
@@ -187,7 +186,7 @@ public function getRules($searchPattern = null)
     /**
      * Overrides all the rules of this set.
      *
-     * @param array<array-key, Rule> $rules The rules to override with.
+     * @param array<Rule> $rules The rules to override with.
      */
     public function setRules(array $rules): void
     {
@@ -212,13 +211,14 @@ public function setRules(array $rules): void
      *
      * @return array<string, Rule>
      */
-    public function getRulesAssoc($searchPattern = null)
+    public function getRulesAssoc($searchPattern = null): array
     {
         /** @var array<string, Rule> $result */
         $result = [];
         foreach ($this->getRules($searchPattern) as $rule) {
             $result[$rule->getRule()] = $rule;
         }
+
         return $result;
     }