Upgrade to Vyper 0.1.0b11

[ghost]

And use @nonreentrant('lock') decorator for addLiquidity, removeLiquidity and swapTokens

[blimp666]

After an upgrade to 0.1.0b11 we will not be able to verify the contract at etherscan (it supports vyper only up to b9 version). Is it ok?

[ghost]

Ah yes, that was the reason. I remember now. Stay at b9.

[blimp666]

Newer Vyper versions up to 0.1.0b12 were recently added at etherscan.io

[ghost]

I've also noticed today. I tried upgrading but the tests started failing. I'm not sure there is much benefit in upgrading to justify the additional development time. What do you think could be the benefits?

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[blimp666]

Yes, you're right, now I see that tests are red with b12 - it fails with Cannot call public functions via 'self' (due to this change vyperlang/vyper@b1c7955 as a part of vyperlang/vyper#1199 ). However tests are green with b11, b11 includes performance and stability fixes, and I think it would be useful to upgrade at least to b11.

As for b12, there are some bugfixes too, but it seems now we can't call public methods internally. As far as I understand it, if we want to use b12, we just should have private methods (like tokenExchangeRateAfterFees) and public wrappers to them. It should not affect a transaction cost, however it will increase a contract size a bit. I guess it shouldn't take long to make our contract compatible with b12.