Make FindPackage substitutions a Path to get operator /

launch_ros/launch_ros/substitutions/find_package.py

@@ -25,11 +25,12 @@
 from launch.launch_context import LaunchContext
 from launch.some_substitutions_type import SomeSubstitutionsType
 from launch.substitution import Substitution
+from launch.substitutions import PathSubstitution
 from launch.utilities import normalize_to_list_of_substitutions
 from launch.utilities import perform_substitutions
 
 
-class FindPackage(Substitution):
+class FindPackage(PathSubstitution):
     """
     Abstract base class for substitutions involving finding a package.
 
@@ -41,7 +42,7 @@ def __init__(
         package: SomeSubstitutionsType,
     ) -> None:
         """Create a FindPackage substitution."""
-        super().__init__()
+        super().__init__(self)
         self.__package = normalize_to_list_of_substitutions(package)
 
     @classmethod

test_launch_ros/test/test_launch_ros/substitutions/test_find_package.py

@@ -36,3 +36,10 @@ def test_find_package_share():
     package_prefix = Path(sub.perform(context))
     package_xml_file = package_prefix / Path('package.xml')
     assert package_xml_file.is_file()
+
+
+def test_find_package_paths():
+    sub = FindPackageShare('launch_ros') / 'package.xml'
+    context = LaunchContext()
+    result_path = sub.perform(context)
+    assert Path(result_path).is_file()