fix: skip codehash check when the code has been deleted in the evm state

[JayT106]

Closes: #1319

just ignores the codehash check when the evm account code is empty.

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[codecov]

Codecov Report

Merging #1320 (6523d81) into main (236ca33) will increase coverage by 0.01%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1320      +/-   ##
==========================================
+ Coverage   55.86%   55.88%   +0.01%     
==========================================
  Files         108      108              
  Lines       10017    10021       +4     
==========================================
+ Hits         5596     5600       +4     
  Misses       4140     4140              
  Partials      281      281              

Impacted Files	Coverage Δ
x/evm/genesis.go	56.66% <100.00%> (+3.09%)	⬆️

[yihuang]

LGTM

[fedekunze]

LGTM. Can you also add a unit test case with the empty code hash here?

[yihuang]

there seems to be conflicts with main?

[yihuang]

LGTM, can we merge this now @fedekunze ?

[danburck]

@yihuang isn't the test with empty code hash still missing?

emptyCodeHash := crypto.Keccak256(nil)
codeHash := common.BytesToHash(emptyCodeHash).String()

[yihuang]

@yihuang isn't the test with empty code hash still missing?

emptyCodeHash := crypto.Keccak256(nil)
codeHash := common.BytesToHash(emptyCodeHash).String()

Which specific case do you have in mind, the default account has the empty code hash, so the previous test cases tested that.