Bug Fix: IndexError in mim command

We recently identified and fixed a bug that caused an IndexError: list index out of range exception when running the mim download command in Conda:

mim download mmsegmentation --config pspnet_r50-d8_4xb2-40k_cityscapes-512x1024 --dest .

The issue occurred in search.py at line 339, where a check for value[0] being an instance of dict was being made without first confirming whether value was empty. This resulted in the following error:

Traceback (most recent call):
  ...
  File "C:\Users\Enbla\anaconda3\envs\openmmlab\lib\site-packages\mim\commands\search.py", line 339, in _parse
    If isinstance(value[0], dict):
IndexError: list index out of range

The fix involves adding an additional check to ensure value is not empty before checking if value[0] is a dictionary instance:

elif isinstance(value, (list, tuple)):
    If value and isinstance(value[0], dict):

Following this fix, re-running the mim command successfully installs the model:

processing pspnet_r50-d8_4xb2-40k_cityscapes-512x1024...
Download ---------------------------------------- 187.1/187.1 MiB 2.5 MB/s eta 0:00:00
Successfully downloaded pspnet_r50-d8_512x1024_40k_cityscapes_20200605_003338-2966598c.pth to C:\Windows\System32
Successfully dumped pspnet_r50-d8_4xb2-40k_cityscapes-512x1024.py to C:\Windows\System32.

We recommend users encountering this issue to update to the latest version where this bug has been addressed.

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