@CyberZHG

You are owner of some files modified in this pull request.
Would you kindly review the changes whenever you have the time to?
Thank you very much.

The original tests mentioned in the ticket was testing model serializzation?
What are you testing with save and load weights?

The original tests mentioned in the ticket was testing model serializzation?
What are you testing with save and load weights?

The description from the ticket was inaccurate. I raised that issue and the problem is on save and reloading. Please check the the discussions in the issue(#2094) for more details.

I was talking about save and reloading original contributor test in https://github.com/CyberZHG/keras-lookahead/blob/master/tests/test_optimizers.py

I was talking about save and reloading original contributor test in https://github.com/CyberZHG/keras-lookahead/blob/master/tests/test_optimizers.py

That is a different way to save a model. The contributor test uses model.save and keras.models.load_model to save and load the entire graph. In our case, we are using model.save_weights and model.load_weights to save and load only the weights of a model.

I was talking about save and reloading original contributor test in https://github.com/CyberZHG/keras-lookahead/blob/master/tests/test_optimizers.py

Just updated the test file referring to the original contributor test. I added cases of whether the inner optimizer contains slots (adam) or not (sgd) and different saving and reloading methods (weights only and whole graph). All tests of "sgd" pass and those of "adam" fail, which I believe should be enough to demonstrate the problem.

Ok, have you double checked https://stackoverflow.com/questions/56805588/does-load-model-load-optimizer-state?

@WindQAQ Let me know if you still find useful to have a save_weight/load_weight test. In that case give a pass over the test.