pure_interface.mypy_plugin [no-redef] error using Delegate

[XavierMilesSeequent]

The plugin does not check for existing definitions when adding methods for pi_attr_delegates. So if the method is defined on the interface, then it will be defined twice, causing a [no-redef] mypy error.

This is the basic setup that I believe should reproduce it. I don't know why the error isn't occurring outside of leapfrog though, so maybe check against modflow_usg.py itself.

import pure_interface


class TwoDUnstructuredModFlowGridBlock:
    def get_voronoi_centres_loader(self):
        return 'Hello'


class IExportableModflowUSGrid(pure_interface.Interface):
    def get_voronoi_centres_loader(self):
        pass


class UnstructuredModFlowGridBlock:
    def __init__(self) -> None:
        self.two_d_grid = TwoDUnstructuredModFlowGridBlock()


@pure_interface.adapts(UnstructuredModFlowGridBlock)
class ExportableUSGrid(pure_interface.Delegate, IExportableModflowUSGrid):
    pi_attr_fallback = 'mf_grid'
    pi_attr_delegates = {
        'two_d_grid': ['get_voronoi_centres_loader']
    }

    def __init__(self, mf_grid: UnstructuredModFlowGridBlock):
        self.mf_grid = mf_grid
        self.two_d_grid = mf_grid.two_d_grid