Conditional PyYAML dependency for atest
# External Python modules required by acceptance tests.
# See atest/README.rst for more information.
-docutils >= 0.9; platform_python_implementation != 'IronPython' # https://github.com/IronLanguages/ironpython2/issues/113
-pygments
-pyyaml
enum34; python_version < '3.0'
pillow; platform_system == 'Windows'
+# https://github.com/IronLanguages/ironpython2/issues/113
+docutils >= 0.9; platform_python_implementation != 'IronPython'
+pygments; platform_python_implementation != 'IronPython'
+
+# https://github.com/yaml/pyyaml/issues/369
+pyyaml; platform_python_implementation != 'Jython'
+pyyaml==5.2; platform_python_implementation == 'Jython'
+
# On Linux installing lxml with pip may require compilation and development
# headers. Alternatively it can be installed using a package manager like
# `sudo apt-get install python-lxml`.
