imp(staking): implement the EditValidator function for staking precompiled contract

[luchenqun]

Description

I have implemented the editValidator function in the #2030, and along with you the previously implemented delegate, undelegate, redelegate and related functions, the staking precompiled contract is only missing the final editValidator. With previous experience, I spent about three hours complete the editValidator.

Some Design Details

For the function editValidator defined in the StakingI.sol file, when the related values in the description parameter are "[do-not-modify]" string, the system will not changing the original values, the design comes from cosmos sdk, see https://github.com/evmos/cosmos-sdk/blob/v0.47.5-evmos/x/staking/client/cli/flags.go#L87-L91 and https://github.com/evmos/cosmos-sdk/blob/v0.47.5-evmos/x/staking/types/validator.go#L213-L241 . Since ths Solidity language does not have like the nil value in the Go language. Therefore, when the commissionRate and minSelfDelegation values are -1, the system keeps the original values unchanged.
Why commissionRate and minSelfDelegation not use the uint256 type and default to 0 without modifying the original value? Because the minimum value of commissionRate can be 0. If you think using -1 without modifying the original value is a reasonable design, I suggest that all subsequent related designs follow this principle.

Testing

Step 1

Set up at least one validator node and check the original information of the validator.

Step 2

Connect to the validator node by Remix and call the editValidator method of the Staking precompiled contract with the following parameters:

• description: [ "[do-not-modify]", "[do-not-modify]", "[do-not-modify]", "[do-not-modify]", "i want update my details" ]
• validatorAddress: 0xbf657D0ef7b48167657A703Ed8Fd063F075246D7
• commissionRate: -1
• minSelfDelegation: 1000000

Note: If you want to test modifying the commissionRate, you need to remove the restriction that it can only be changed once a day in cosmos sdk. For details see the code: https://github.com/evmos/cosmos-sdk/blob/v0.47.5-evmos/x/staking/types/commission.go#L86-L88

Step 3

Verify if the modifications have taken effect

• The details value in the description has changed, while the others remain unchanged.
• Since -1 was passed, the commissionRate value remains unchanged.
• The minSelfDelegation value has changed from 1 to 1000000.

Query EVM transactions.

Query Cosmos transactions.

[codecov]

Codecov Report

Attention: Patch coverage is 93.87755% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 59.66%. Comparing base (f097735) to head (4844766).
Report is 153 commits behind head on main.

❗ Current head 4844766 differs from pull request most recent head d25a4ec

Please upload reports for the commit d25a4ec to get more accurate results.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #2051       +/-   ##
===========================================
- Coverage   70.45%   59.66%   -10.79%     
===========================================
  Files         293      341       +48     
  Lines       22559    21676      -883     
===========================================
- Hits        15893    12934     -2959     
- Misses       5800     7693     +1893     
- Partials      866     1049      +183     

Files	Coverage Δ
precompiles/staking/types.go	90.02% <100.00%> (+2.69%)	⬆️
precompiles/staking/events.go	76.96% <91.30%> (+4.59%)	⬆️
precompiles/staking/staking.go	85.00% <0.00%> (+2.04%)	⬆️
precompiles/staking/tx.go	88.65% <89.47%> (+0.28%)	⬆️

... and 342 files with indirect coverage changes

[Vvaradinov]

Great work on this @luchenqun . Left some comments

[Vvaradinov]

Hey @luchenqun lefts some additional comments. Please also address the changes @fedekunze requested on the string coversion

[GAtom22]

thanks for the contribution @luchenqun!