feat: print event definitions

[Bobface]

Motivation

Getting information about events, such as their signature, is a useful feature. Cast already offers that through cast sig-event, and this PR adds a similar feature for Chisel.

Solution

When parsing the latest line with let line = format!("bytes memory inspectoor = abi.encode({input});"); fails, do not return early but instead check whether the latest line is the name of an event and if that's the case, print information about the event.

Example

Welcome to Chisel! Type `!help` to show available commands.
➜ event SomeEvent(uint256 indexed amount, address indexed user, uint32 index);
➜ SomeEvent
Type: event
├ Name: SomeEvent
└ Signature: 0xc7b1e4c8001505f9934d5ee0d745935c3b1cf0a9eef39860f497c15f9ec9a1be
➜ event SomeOtherEvent(address);
➜ SomeOtherEvent
Type: event
├ Name: SomeOtherEvent
└ Signature: 0xe311a95f689f1b8f6494d8ff8243f05aae06ecc0d44b37b56e8d704901cac8bb
➜

[mattsse]

tbh not exactly sure what this does.

@clabby @DaniPopes would appreciate a review

[Bobface]

The idea is that you can print information about events.

For example, for variables you can already do

uint a = 123;
a

and it will give you information about the variable.

If you do

event SomeEvent(address user)
SomeEvent

nothing is printed. This PR adds support for printing the event's name and most importantly its signature.

Regarding requested changes I would wait until all reviews are complete and then do them in a single commit.

[mattsse]

@clabby friendly ping :)

[DaniPopes]

Also needs cargo +nightly fmt

[Bobface]

Implemented the changes.

[clabby]

nice work!

[clabby]

LGTM

[Bobface]

Added the missing SolidityHelper import which caused the build to fail.

[Bobface]

Hey, checking in on this :)

[Evalir]

lgtm! finally getting this in. we can improve on verbosity in subsequent prs