4x ENS functionality

[jdevcs]

Description

#4552
#4602
#4553

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Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

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[lgtm-com]

This pull request introduces 1 alert when merging 0ec2465 into ea41c55 - view on LGTM.com

new alerts:

• 1 for Unused variable, import, function or class

[luu-alex]

i think unit tests for the resolver class would be good, other then that LGTM

[jdevcs]

i think unit tests for the resolver class would be good, other then that LGTM

@luu-alex Resolver class is only sending transactions and sending eth_calls for reads so I think we can test it in integration tests.

[spacesailor24]

You could do this in a subsequent PR, but I think packages/web3-eth-ens/src/ens.ts should have sanity check unit tests that test this._resolver is receiving the expected arguments from ENS class - this ensures the user facing API never changes accidentally

[luu-alex]

@spacesailor24 i included add sanity check for resolver in the ens epic, so we can merge this one in