Fix wrong precision in calculation of gas fee

[KamiD]

Closes: #799

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[araskachoi]

@KamiD
This fix does not fix #799. The proposed fix here will make the multiplier into 18*10^18, which will break the default precision calculation. could you revisit this and see if it is actually an issue?

[KamiD]

@KamiD
This fix does not fix #799. The proposed fix here will make the multiplier into 18*10^18, which will break the default precision calculation. could you revisit this and see if it is actually an issue?

hi, I have test this case in ut and debug in step by step, that is actually an issue here.
for math example:

• set gas price to 1 GWEI, set gas limit to 10000
• in AnteHandler, the code fee = price * GasLimit should be 10000000000000, that's a correct value
• if I use old code, the result of fee will be 10000000000000 ^ 18 cause NewDecCoin will call func ToDec() and it will change the value to n ^ 18
• if I use the new code, the result of fee will be 10000000000000

in case of using function NewDecCoinFromDec , if I set the param prec to 0, the result will be n ^ 18, if I set prec to 18, the result will be n ^ 0, after debugging and running tests case on okexchain, this pr will fix the precision error.

BTW: the function NewDecCoinFromDec was a little anti-humanity

[araskachoi]

tested and works as intended!
@KamiD can we write a quick precision test to make sure that the fee has the correct decimal precision? looks ready to approve/merge after that. thanks!

[fedekunze]

ACK. Can you add a changelog entry?

[araskachoi]

@KamiD can you update the changelog file please? ready to merge afterwards. apologies on the delay

[KamiD]

@KamiD can you update the changelog file please? ready to merge afterwards. apologies on the delay

hey bro, its done