Add generic types to traversable implementations

Author: derrabus

InputStream.php

@@ -17,6 +17,8 @@
  * Provides a way to continuously write to the input of a Process until the InputStream is closed.
  *
  * @author Nicolas Grekas <p@tchwork.com>
+ *
+ * @implements \IteratorAggregate<int, string>
  */
 class InputStream implements \IteratorAggregate
 {
@@ -67,7 +69,7 @@ public function isClosed()
     }
 
     /**
-     * @return \Traversable
+     * @return \Traversable<int, string>
      */
     #[\ReturnTypeWillChange]
     public function getIterator()

Process.php

@@ -27,6 +27,8 @@
  *
  * @author Fabien Potencier <fabien@symfony.com>
  * @author Romain Neutron <imprec@gmail.com>
+ *
+ * @implements \IteratorAggregate<string, string>
  */
 class Process implements \IteratorAggregate
 {
@@ -618,7 +620,7 @@ public function getIncrementalOutput()
      * @throws LogicException in case the output has been disabled
      * @throws LogicException In case the process is not started
      *
-     * @return \Generator
+     * @return \Generator<string, string>
      */
     #[\ReturnTypeWillChange]
     public function getIterator(int $flags = 0)