def instantiate_extensions(group_name,
*,
exclude_names=None,
unique_instance=False):
"""
Instantiate all extensions within a group.
:param str group_name: the name of the `entry_point` group
:param exclude_names: a list of entry point names to exclude
:param bool unique_instance: The flag if each extensions should be
instantiated even when it has been created and cached before
:returns: dict of extensions
"""
extension_types = load_entry_points(group_name,
exclude_names=exclude_names)
extension_instances = {}
for extension_name, extension_class in extension_types.items():
extension_instance = _instantiate_extension(
group_name,
extension_name,
extension_class,
unique_instance=unique_instance)
if extension_instance is None:
continue
extension_instances[extension_name] = extension_instance
return extension_instances
def test_load_entry_points_with_exception(_):
with patch('colcon_core.entry_point.logger.error') as error:
extensions = load_entry_points('group')
# the entry point raising an exception different than a runtime error
# results in an error message
assert error.call_count == 1
assert len(error.call_args[0]) == 1
assert "Exception loading extension 'group.exception'" \
in error.call_args[0][0]
assert 'entry point raising exception' in error.call_args[0][0]
# neither of the entry points was loaded successfully
assert extensions == {'success': None}
def get_environment_variables_epilog(group_name):
"""
Get a message enumerating the registered environment variables.
:param str group_name: The entry point group name for the environment
variable extensions
:returns: The message for the argument parser epilog
:rtype: str
"""
# list environment variables with descriptions
entry_points = load_entry_points(group_name)
env_vars = {
env_var.name: env_var.description for env_var in entry_points.values()}
epilog_lines = []
for name in sorted(env_vars.keys()):
epilog_lines += _format_pair(name, env_vars[name], indent=2, align=24)
return 'Environment variables:\n' + '\n'.join(epilog_lines)
def get_python_testing_step_extension(step_name):
"""
Get a specific Python testing step extension.
:param str step_name: The entry point name of the extension
:returns: A unique instance of the extension, otherwise None
"""
group_name = 'colcon_core.python_testing'
extension_types = load_entry_points(group_name)
extension_names = list(extension_types.keys())
if step_name not in extension_names:
return None
extension_names.remove(step_name)
extensions = instantiate_extensions(
group_name, exclude_names=extension_names, unique_instance=True)
if step_name not in extensions:
return None
extension = extensions[step_name]
extension.STEP_NAME = step_name
return extension
