Fix handling of telescope parameters from cli for string values, fixes …

…#1559 (#1560)

ctapipe/core/tests/test_traits.py

@@ -433,6 +433,33 @@ class SomeComponent(TelescopeComponent):
  assert config["SomeComponent"]["tel_param1"] == [("type", "*", 6.0)]
 
 
+def test_telescope_parameter_from_cli(mock_subarray):
+ """
+ Test we can pass single default for telescope components via cli
+ see #1559
+ """
+
+ from ctapipe.core import Tool, run_tool
+
+ class SomeComponent(TelescopeComponent):
+ path = TelescopeParameter(Path(), default_value=None).tag(config=True)
+ val = TelescopeParameter(Float(), default_value=1.0).tag(config=True)
+
+ class TelescopeTool(Tool):
+ def setup(self):
+ self.comp = SomeComponent(subarray=mock_subarray, parent=self)
+
+ tool = TelescopeTool()
+ run_tool(tool)
+ assert tool.comp.path == [("type", "*", None)]
+ assert tool.comp.val == [("type", "*", 1.0)]
+
+ tool = TelescopeTool()
+ run_tool(tool, ["--SomeComponent.path", "test.h5", "--SomeComponent.val", "2.0"])
+ assert tool.comp.path == [("type", "*", pathlib.Path("test.h5").absolute())]
+ assert tool.comp.val == [("type", "*", 2.0)]
+
+
 def test_datetimes():
  from astropy import time as t
 

ctapipe/core/traits.py

@@ -357,20 +357,25 @@ class TelescopeParameter(List):
  """
 
  klass = TelescopePatternList
+ _valid_defaults = (object,) # allow everything, we validate the default ourselves
 
  def __init__(self, trait, default_value=Undefined, **kwargs):
+
  if not isinstance(trait, TraitType):
  raise TypeError("trait must be a TraitType instance")
 
- if (
- not isinstance(default_value, (UserList, list, List))
- and default_value is not Undefined
- ):
- default_value = trait.validate(self, default_value)
- default_value = [("type", "*", default_value)]
+ self._trait = trait
+ if default_value != Undefined:
+ default_value = self.validate(self, default_value)
 
  super().__init__(default_value=default_value, **kwargs)
- self._trait = trait
+
+ def from_string(self, s):
+ val = super().from_string(s)
+ # for strings, parsing fails and traitlets returns None
+ if val == [("type", "*", None)] and s != "None":
+ val = [("type", "*", self._trait.from_string(s))]
+ return val
 
  def validate(self, obj, value):
  # Support a single value for all (check and convert into a default value)