Refactor loader_cfg.

[Yshuo-Li]

Refactor loader_cfg of main() in tools/test.py.

There is a bug in the master branch:
TypeError: type object got multiple values for keyword argument 'samples_per_gpu'.

That is because loader_cfg contains two 'samples_per_gpu':

1. samples_per_gpu=1,
2. **cfg.data.get('test_dataloader', {}),, while cfg.data['test_dataloader']=dict(samples_per_gpu=1),

The second one has been replaced by loader_cfg.update(cfg.data.get('test_dataloader', {})).

[codecov]

Codecov Report

Merging #214 (857a3b2) into master (4f90c0c) will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master     #214   +/-   ##
=======================================
  Coverage   82.27%   82.27%           
=======================================
  Files         145      145           
  Lines        6732     6732           
  Branches     1004     1004           
=======================================
  Hits         5539     5539           
  Misses       1086     1086           
  Partials      107      107           

Flag	Coverage Δ
unittests	82.27% <0.00%> (ø)

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Impacted Files	Coverage Δ
mmedit/apis/train.py	20.98% <0.00%> (ø)

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[innerlee]

Thanks! I will check shortly

[innerlee]

Yeah thanks for the findings. It indeed causes error. I got another fancy way of merging dicts, do you want to check it out?

loader_cfg = {
    **dict((k, cfg.data[k]) for k in ['workers_per_gpu'] if k in cfg.data),
    **dict(samples_per_gpu=1,
           drop_last=False,
           shuffle=False,
           dist=distributed),
    **cfg.data.get('train_dataloader', {})}

[innerlee]

Thanks, there are other places need to be modified: train.py L104, L170 and L278.

[innerlee]

pls install pre-commit and let it pass the lint :)

[innerlee]

No there is no need to add this dict

[innerlee]

Tests are failing

[innerlee]

loader_cfg is a dict. To better demostrate the priority, put it outside

    **loader_cfg,
    **dict(shuffle=False, drop_last=False),

[innerlee]

Thanks a lot!