Sorting coins of the genesis balances is no effect

[whylee259]

Summary of Bug

https://github.com/cosmos/cosmos-sdk/blob/master/x/bank/types/balance.go#L57-L58

From the above code, Sort() is no effect due to the value receiver.
If the sorting is intended, the receiver should be a pointer receiver.

func (b *Balance) Validate() error {
...
}

Version

current master branch (615f224)

Steps to Reproduce

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For Admin Use

• Not duplicate issue
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• Appropriate contributors tagged
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[tac0turtle]

@alexanderbez @AmauryM do you know if sorting was intended?

[alexanderbez]

This is a certainly a code-smell! Validate should be stateless and not mutate, i.e. it should have no side effects. This is a bug. Want to submit a PR @marbar3778?

[amaury1093]

Agreed. I would just throw an error if the coins are not sorted.

Since @whylee259 you found the bug, maybe you want to create a PR?

[spoo-bar]

If @marbar3778 or @whylee259 aren't working on this, maybe I will take this? 😊

[alexanderbez]

Please and thank you @spoo-bar 🙏