Event declared twice

[Psyf]

The following event is declared twice, one in the Subscriptions.sol Library and once in the ISubscription.sol interface (implemented by Fund.sol).
event Deposit(address subscriber, uint256 subIdx, address token, uint256 balance);

When a Contract uses a library, underneath the hood it is a delegateCall. So when Fund calls a library function from SubLib, it's a delegateCall from Fund to SubLib (which is why libraries can't access storage directly, and have to be passed a pointer specifically).

If we don't include the event in ISubscription however, the event is never emitted (since the abi for Fund doesn't have the event?)

A similar problem arises when we're emitting events from Utils.create_position and Utils.close_positions.

Not having the event in the abi manifests problems in Matcha Tests and The Graph's subgraphs.

There are 2 solutions:

• copypasta the events in 2 places. Manual and error-prone labour of making sure they're synced.
• modify the contract such that the library is not responsible for emitting events.

[Psyf]

Goolging brought these up:

• Allow Event Definitions at File Level ethereum/solidity#9737
• Export used events (and errors) instead of just declared ethereum/solidity#9765

[Psyf]

Fixed in graph::1c271cf