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Array parameters wierdness

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
30/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
tooling

Research direction

No source files or tests are named. Start by tracing how parameters.yaml types, defaults, and validation rules are parsed, then reproduce the three configurations in the issue. Done means array parameters remain arrays with bounds, with and without a default value, and the reported integer-versus-integer_array error is resolved.

Written by the indexing model from the issue text.

Description

bug

There seem to be some issues with the handling of array parameters. I'm encountering problems with setting parameters and getting my application terminated, because of

Wrong parameter type, parameter {myParam} is of type {integer}, setting it to {integer_array} is not allowed.
Working configuration:

parameters.yaml

  myParam: {
    type: int_array_fixed_2,
    description: "myDescription",
    default_value: [ 0, 0],
    validation: {
      element_bounds<>: [ 0, 10000 ]
    }
  }

config.yaml

node:
  ros__parameters:
    myParam: [0, 1]
bounds demoting array to single integer

parameters.yaml

  myParam: {
    type: int_array_fixed_2,
    description: "myDescription",
    default_value: [ 0, 0],
    validation: {
      bounds<>: [ 0, 10000 ]
    }
  }

Changing out element_bounds to bounds will demote the parameter to a single integer and cause the error at the start. Removing the validation block will fix the problem.

No default_value demotes to single integer

parameters.yaml

  myParam: {
    type: int_array_fixed_2,
    description: "myDescription",
    validation: {
      element_bounds<>: [ 0, 10000 ]
    }
  }

Removing the default_value key will also demote the array. Removing the validation block will change nothing.

Something fishy is going on here, could you have a look? Thank you <3

Dominant language
Python
Stars
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Forks
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