Make ConstantArrayType::getOffsetType most likely a bit more correct

phpstan · Jul 13, 2022 · b51b928 · b51b928
1 parent e994f69
commit b51b928
Showing 1 changed file with 6 additions and 3 deletions.
diff --git a/src/Type/Constant/ConstantArrayType.php b/src/Type/Constant/ConstantArrayType.php
@@ -540,13 +540,16 @@ public function getOffsetType(Type $offsetValueType): Type
 				return $traverse($type);
 			}
 
+			$offsetType = new NeverType();
 			foreach ($this->valueTypes as $i => $valueType) {
-				if ($valueType->equals($type)) {
-					return $this->keyTypes[$i];
+				if (!$type->isSuperTypeOf($valueType)->yes()) {
+					continue;
 				}
+
+				$offsetType = TypeCombinator::union($offsetType, $this->keyTypes[$i]);
 			}
 
-			return new ErrorType(); // undefined offset value
+			return $offsetType instanceof NeverType ? new ErrorType() : $offsetType;
 		});
 	}