StationConfigurator

environment.yml

@@ -22,11 +22,11 @@ dependencies:
  - pyyaml
  - lxml
  - scipy
- - ruamel_yaml
  - gitpython
  - pandas
  - testpath>=0.4.2 # 0.4.1 is bad due to https://github.com/conda-forge/testpath-feedstock/issues/7
  - tqdm
  - pip:
     - websockets>=7.0
     - broadbean>=0.9.1
+    - ruamel.yaml

qcodes/dataset/descriptions.py

@@ -2,9 +2,11 @@
 from typing import Dict, Any, Union, cast
 import json
 
+from qcodes.utils.helpers import YAML
 from qcodes.dataset.dependencies import (InterDependencies,
                                          InterDependencies_,
                                          new_to_old)
+
 SomeDeps = Union[InterDependencies, InterDependencies_]
 
 
@@ -81,26 +83,10 @@ def _is_description_old_style(serialized_object: Dict[str, Any]) -> bool:
         else:
             return False
 
-    @staticmethod
-    def _ruamel_importer():
-        try:
-            from ruamel_yaml import YAML
-        except ImportError:
-            try:
-                from ruamel.yaml import YAML
-            except ImportError:
-                raise ImportError('No ruamel module found. Please install '
-                                  'either ruamel.yaml or ruamel_yaml to '
-                                  'use the methods to_yaml and from_yaml')
-        return YAML
-
     def to_yaml(self) -> str:
         """
         Output the run description as a yaml string
         """
-
-        YAML = self._ruamel_importer()
-
         yaml = YAML()
         with io.StringIO() as stream:
             yaml.dump(self.serialize(), stream=stream)
@@ -120,9 +106,6 @@ def from_yaml(cls, yaml_str: str) -> 'RunDescriber':
         Parse a yaml string (the return of `to_yaml`) into a RunDescriber
         object
         """
-
-        YAML = cls._ruamel_importer()
-
         yaml = YAML()
         # yaml.load returns an OrderedDict, but we need a dict
         ser = dict(yaml.load(yaml_str))

qcodes/instrument/parameter.py

@@ -930,8 +930,11 @@ def __init__(self, name: str,
                  **kwargs) -> None:
         super().__init__(name=name, instrument=instrument, vals=vals, **kwargs)
 
-        # Enable set/get methods if get_cmd/set_cmd is given
-        # Called first so super().__init__ can wrap get/set methods
+        # Enable set/get methods from get_cmd/set_cmd if given and
+        # no `get`/`set` or `get_raw`/`set_raw` methods have been defined
+        # in the scope of this class.
+        # (previous call to `super().__init__` wraps existing get_raw/set_raw to
+        # get/set methods)
         if not hasattr(self, 'get') and get_cmd is not False:
             if get_cmd is None:
                 if max_val_age is not None:
@@ -2012,6 +2015,58 @@ def set_raw(self, value: Union[int, float]) -> None:
         self._wrapped_parameter.set(instrument_value)
 
 
+class DelegateParameter(Parameter):
+    """
+    The `DelegateParameter` wraps a given `source`-parameter. Setting/getting
+    it results in a set/get of the source parameter with the provided
+    arguments.
+
+    The reason for using a `DelegateParameter` instead of the source parameter
+    is to provide all the functionality of the Parameter base class without
+    overwriting properties of the source: for example to set a different
+    Scaling factor and unit on the `DelegateParameter` without changing those
+    in the source parameter
+    """
+
+    def __init__(self, name: str, source: Parameter, *args, **kwargs):
+        self.source = source
+
+        for ka, param in zip(('unit', 'label', 'snapshot_value'),
+                             ('unit', 'label', '_snapshot_value')):
+            kwargs[ka] = kwargs.get(ka, getattr(self.source, param))
+
+        for cmd in ('set_cmd', 'get_cmd'):
+            if cmd in kwargs:
+                raise KeyError(f'It is not allowed to set "{cmd}" of a '
+                               f'DelegateParameter because the one of the '
+                               f'source parameter is supposed to be used.')
+
+        super().__init__(name, *args, **kwargs)
+
+    # Disable the warnings until MultiParameter and ArrayParameter have been
+    # replaced and name/label/unit can live in _BaseParameter
+    # pylint: disable=method-hidden
+    def get_raw(self):
+        return self.source.get()
+
+    # same as for `get_raw`
+    # pylint: disable=method-hidden
+    def set_raw(self, value):
+        self.source(value)
+
+    def snapshot_base(self,
+                      update: bool = False,
+                      params_to_skip_update: Sequence[str] = None):
+        snapshot = super().snapshot_base(
+            update=update,
+            params_to_skip_update=params_to_skip_update
+        )
+        snapshot.update(
+            {'source_parameter': self.source.snapshot(update=update)}
+        )
+        return snapshot
+
+
 def expand_setpoints_helper(parameter: ParameterWithSetpoints) -> List[
         Tuple[_BaseParameter, numpy.ndarray]]:
     """