(fix) allow full EVM access to unlocked tokens

[0a1c]

Description

Grant full EVM access to unlocked tokens, which by definition have no restrictions—and enable a user to make full use of their spendable balance.

By removing the AnteHandler locked token check, we allow the bank module to apply its accounting logic to every EVM state-change. See the spec for more details on how this solution works.

We include additional AnteHandler checks to make sure that if a transaction would fail because it attempts to spend unlocked tokens, we reject it and don't process it.

Edits

• Updated spec to clarify context and solution
• Updated description

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[linear]

ENG-1117 EVM transactions fail on vesting account for unlocked tokens when account has locked tokens

Impact

On a vesting account, unlocked tokens can't be used on the EVM at all, meaning

1. MetaMask users can't send funds on a vesting account (with and without ledger)
2. MetaMask users can't do any contract interactions like LPing, lending, or providing liquidity on a vesting account.
3. MetaMask users with a vesting account have to migrate their funds off of their wallet to use those unlocked tokens on the EVM, via a non EVM tx, which is possible through dashboards like Disperze.Network.

Since vesting accounts are still increasing in adoption and we have a vesting UI being worked on, we should consider working on a fix soon to improve the vesting accounts implementation and fix all of its bugs.

What should be happening instead

Unlocked tokens that are vested, those are free to do whatever and shouldn't be bound by the EVM or restricted.

Why it happens

Currently, EVM transactions are blocked on Evmos if the account has any locked tokens, rather than if the tokens in question are locked. This is problematic because it delays access to unlocked tokens for much longer than is necessary (in many cases, this means multiple years).

Possible Solution

• Look into using SpendableCoins, which should maintain a balance of unlocked tokens

Slack thread for context:

https://evmos.slack.com/archives/C02QAFZFSTA/p1669682548184549?thread_ts=1669594767.974709&cid=C02QAFZFSTA

[codecov]

Codecov Report

Merging #1268 (40ab7a8) into main (8aa1736) will increase coverage by 0.10%.
The diff coverage is 85.96%.

❗ Current head 40ab7a8 differs from pull request most recent head 047d53a. Consider uploading reports for the commit 047d53a to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1268      +/-   ##
==========================================
+ Coverage   72.27%   72.38%   +0.10%     
==========================================
  Files         259      259              
  Lines       17640    17658      +18     
==========================================
+ Hits        12750    12781      +31     
+ Misses       4321     4308      -13     
  Partials      569      569              

Impacted Files	Coverage Δ
app/ante/handler_options.go	30.52% <0.00%> (ø)
x/vesting/types/clawback_vesting_account.go	96.74% <ø> (ø)
app/ante/evm/vesting.go	88.46% <87.50%> (+53.16%)	⬆️
x/claims/keeper/msg_server.go	66.66% <0.00%> (-24.51%)	⬇️
x/claims/keeper/keeper.go	84.61% <0.00%> (-0.57%)	⬇️
x/evm/types/errors.go	0.00% <0.00%> (ø)
ethereum/eip712/encoding.go	76.68% <0.00%> (ø)
x/claims/keeper/ibc_callbacks.go	97.76% <0.00%> (ø)

[fedekunze]

It looks like there are a lot of duplicated test utils. Please reuse existing functions

[fedekunze]

ACK

addressed