[BUGFIX] Avoid double autoloading of class aliases

CHANGELOG.md

@@ -20,6 +20,8 @@ Please also have a look at our
 
 ### Fixed
 
+- Avoid double autoloading of class aliases (#1552)
+
 ### Documentation
 
 ## 9.2.0: New features and deprecations

src/Rule/Rule.php

@@ -8,7 +8,10 @@
 
 use function Safe\class_alias;
 
-/**
- * @deprecated in v9.2, will be removed in v10.0.  Use `Property\Declaration` instead, which is a direct replacement.
- */
-class_alias(Declaration::class, Rule::class);
+if (!\class_exists(Rule::class, false) && !\interface_exists(Rule::class, false)) {
+    /**
+     * @deprecated in v9.2, will be removed in v10.0.  Use `Property\Declaration` instead, which is a direct
+     *             replacement.
+     */
+    class_alias(Declaration::class, Rule::class);
+}

src/RuleSet/RuleContainer.php

@@ -6,7 +6,9 @@
 
 use function Safe\class_alias;
 
-/**
- * @deprecated in v9.2, will be removed in v10.0.  Use `DeclarationList` instead, which is a direct replacement.
- */
-class_alias(DeclarationList::class, RuleContainer::class);
+if (!\class_exists(RuleContainer::class, false) && !\interface_exists(RuleContainer::class, false)) {
+    /**
+     * @deprecated in v9.2, will be removed in v10.0.  Use `DeclarationList` instead, which is a direct replacement.
+     */
+    class_alias(DeclarationList::class, RuleContainer::class);
+}