bugfix: prevent infinite-loop when resolving type-aliases

The type-expander returns the same `intersection_type` in case something is not properly expandable. To avoid infinite-loop, we do explicitly verify that the expanded alias is actually resolved Signed-off-by: Maximilian Bösing <2189546+boesing@users.noreply.github.com>
vimeo · Aug 27, 2023 · 58b55d0 · 58b55d0
1 parent 77436b1
commit 58b55d0
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/src/Psalm/Internal/Type/TypeParser.php b/src/Psalm/Internal/Type/TypeParser.php
@@ -1629,9 +1629,7 @@ private static function resolveTypeAliases(Codebase $codebase, array $intersecti
                 continue;
             }
 
-            $modified = true;
-
-            $normalized_intersection_types[] = TypeExpander::expandAtomic(
+            $expanded_intersection_type = TypeExpander::expandAtomic(
                 $codebase,
                 $intersection_type,
                 null,
@@ -1644,6 +1642,9 @@ private static function resolveTypeAliases(Codebase $codebase, array $intersecti
                 true,
                 true,
             );
+
+            $modified = $normalized_intersection_types[0] !== $intersection_type;
+            $normalized_intersection_types[] = $expanded_intersection_type;
         }
 
         if ($modified === false) {