# Copyright 2008-2015 Nokia Networks
# Copyright 2016- Robot Framework Foundation
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from robot.errors import DataError
from robot.utils import get_error_message, is_list_like, type_name
from .arguments import PythonArgumentParser
from .context import EXECUTION_CONTEXTS
[docs]
def no_dynamic_method(*args):
return None
[docs]
class DynamicMethod:
_underscore_name = NotImplemented
def __init__(self, instance):
self.instance = instance
self.method = self._get_method(instance)
def _get_method(self, instance):
for name in self._underscore_name, self._camelCaseName:
method = getattr(instance, name, None)
if callable(method):
return method
return no_dynamic_method
@property
def _camelCaseName(self):
tokens = self._underscore_name.split('_')
return ''.join([tokens[0]] + [t.capitalize() for t in tokens[1:]])
@property
def name(self):
return self.method.__name__
def __call__(self, *args, **kwargs):
try:
ctx = EXECUTION_CONTEXTS.current
result = self.method(*args, **kwargs)
if ctx and ctx.asynchronous.is_loop_required(result):
result = ctx.asynchronous.run_until_complete(result)
return self._handle_return_value(result)
except Exception:
raise DataError(f"Calling dynamic method '{self.name}' failed: "
f"{get_error_message()}")
def _handle_return_value(self, value):
raise NotImplementedError
def _to_string(self, value, allow_tuple=False, allow_none=False):
if isinstance(value, str):
return value
if isinstance(value, bytes):
return value.decode('UTF-8')
if allow_tuple and is_list_like(value) and len(value) > 0:
return tuple(value)
if allow_none and value is None:
return value
allowed = 'a string or a non-empty tuple' if allow_tuple else 'a string'
raise DataError(f'Return value must be {allowed}, got {type_name(value)}.')
def _to_list(self, value):
if value is None:
return ()
if not is_list_like(value):
raise DataError
return value
def _to_list_of_strings(self, value, allow_tuples=False):
try:
return [self._to_string(item, allow_tuples)
for item in self._to_list(value)]
except DataError:
allowed = 'strings or non-empty tuples' if allow_tuples else 'strings'
raise DataError(f'Return value must be a list of {allowed}, '
f'got {type_name(value)}.')
def __bool__(self):
return self.method is not no_dynamic_method
[docs]
class GetKeywordNames(DynamicMethod):
_underscore_name = 'get_keyword_names'
def _handle_return_value(self, value):
names = self._to_list_of_strings(value)
return list(self._remove_duplicates(names))
def _remove_duplicates(self, names):
seen = set()
for name in names:
if name not in seen:
seen.add(name)
yield name
[docs]
class RunKeyword(DynamicMethod):
_underscore_name = 'run_keyword'
def __init__(self, instance, keyword_name: 'str|None' = None,
supports_named_args: 'bool|None' = None):
super().__init__(instance)
self.keyword_name = keyword_name
self._supports_named_args = supports_named_args
@property
def supports_named_args(self) -> bool:
if self._supports_named_args is None:
spec = PythonArgumentParser().parse(self.method)
self._supports_named_args = len(spec.positional) == 3
return self._supports_named_args
def __call__(self, *positional, **named):
if self.supports_named_args:
args = (self.keyword_name, positional, named)
elif named:
# This should never happen.
raise ValueError(f"'named' should not be used when named-argument "
f"support is not enabled, got {named}.")
else:
args = (self.keyword_name, positional)
return self.method(*args)
[docs]
class GetKeywordDocumentation(DynamicMethod):
_underscore_name = 'get_keyword_documentation'
def _handle_return_value(self, value):
return self._to_string(value or '')
[docs]
class GetKeywordArguments(DynamicMethod):
_underscore_name = 'get_keyword_arguments'
def __init__(self, instance, supports_named_args: 'bool|None' = None):
super().__init__(instance)
if supports_named_args is None:
self.supports_named_args = RunKeyword(instance).supports_named_args
else:
self.supports_named_args = supports_named_args
def _handle_return_value(self, value):
if value is None:
if self.supports_named_args:
return ['*varargs', '**kwargs']
return ['*varargs']
return self._to_list_of_strings(value, allow_tuples=True)
[docs]
class GetKeywordTypes(DynamicMethod):
_underscore_name = 'get_keyword_types'
def _handle_return_value(self, value):
return value if self else {}
[docs]
class GetKeywordSource(DynamicMethod):
_underscore_name = 'get_keyword_source'
def _handle_return_value(self, value):
return self._to_string(value, allow_none=True)