Support for named parameters in mappings (Solidity v0.8.18)

[PaulRBerg]

Solidity v0.8.18 was released earlier this week, and one of the newly introduced features are named parameters in mappings. That means that we can now define mappings like this:

contract Foo {
    mapping(address key => uint256 value) public items;
    mapping(string name => uint256 balance) public users;
}

Solhint throws with the following error when it sees the code above:

Linter: Parse error: extraneous input 'key' expecting '=>' [undefined]

[fvictorio]

Two things to do here:

1. Update the parser (I already added support for named mapping parameters in it)
2. Open an issue about adding a new rule that suggests using named parameters. This rule will only make sense for solidity >=0.8.18, so it should be disabled by default, and not included in the recommended preset config.

[PaulRBerg]

Agree, a rule would be cool. But I think until the rule gets added, just adding support for the parsing would be helpful.

[andreivladbrg]

Hey @fvictorio, do you have any updates on this? My github actions are failing because of this.

[gitpusha]

Would be great to get support for this!

[cyberhorsey]

Also would love this : )

[dbale-altoros]

Guys, I created a new rule for this in this PR
#403

[PaulRBerg]

Looks like this issue can be closed now, since v3.4.0 includes support for named mapping params 🥳

https://github.com/protofire/solhint/blob/37d9b14883c4aac29fde19e4b0bf15996bda6953/CHANGELOG.md