R4R: Add custom validation for denom

[okwme]

Description

Allow ValidateDenom to be customized per application.

closes: #6744

---

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[okwme]

@alessio I added the technique you described in #6744 but I'm still unsure how as an app developer I would utilize this change. When I add modules to my app.go is it possible to somehow overwrite the ValidateDenom with a new function? This wouldn't necessarily be honored by other modules which import the Coin type though right? Or does this need a more complicated architecture where the validation rules are stored somewhere else?

[codecov]

Codecov Report

Merging #6755 into master will decrease coverage by 0.25%.
The diff coverage is 71.42%.

@@            Coverage Diff             @@
##           master    #6755      +/-   ##
==========================================
- Coverage   55.50%   55.24%   -0.26%     
==========================================
  Files         440      591     +151     
  Lines       29169    36949    +7780     
==========================================
+ Hits        16190    20414    +4224     
- Misses      11352    14427    +3075     
- Partials     1627     2108     +481     

[colin-axner]

This is unrelated to your question above, but with regards to IBC it would be cool if a custom denomination on chainA that is not supported by chainB could still be transferred to chainB without error. I think this should work fine if we represent denominations as hashes of the IBC path, assuming chainB supports hashes as denoms.

cc/ @cwgoes @fedekunze

[alessio]

👍

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[okwme]

sorry, making this a priority this week

[okwme]

Would love some help understanding why test coverage is failing.
@marbar3778 @fedekunze any ideas?

[alessio]

Would love some help understanding why test coverage is failing.

@okwme 'cause codecov.io sucks in so many different ways. I will review again when it's ready, though so far code looks good, test cases seem sufficient. Don't bother please and keep up the good work!

[tac0turtle]

Would love some help understanding why test coverage is failing.

seems to be missing some values:

# github.com/cosmos/cosmos-sdk/types_test [github.com/cosmos/cosmos-sdk/types.test]
types/coin_test.go:104:2: undefined: CoinDenomRegex
types/coin_test.go:109:14: undefined: Coin
types/coin_test.go:112:4: undefined: Coin
types/coin_test.go:113:4: undefined: Coin
types/coin_test.go:114:4: undefined: Coin
types/coin_test.go:115:4: undefined: Coin
types/coin_test.go:116:4: undefined: Coin
types/coin_test.go:120:3: undefined: require
types/coin_test.go:122:2: undefined: CoinDenomRegex
types/coin_test.go:122:19: undefined: DefaultCoinDenomRegex
types/coin_test.go:122:19: too many errors

does this not happen when running tests locally?

[okwme]

@marbar3778 oops the test format totally changed from v0.38. Passing now.

[alessio]

@okwme this should be moved across the the Launchpad branch as 0.39.2 will be the first release where this new feature is introduced.