Slow type-checking in ChatMessageImageAttachment.swift

[pm-dev]

What did you do?

Checked type-checking in our project and found a couple lines that took a while to type-check

xcodebuild clean build -project <YOUR PROJECT FILE NAME>.xcodeproj/ OTHER_SWIFT_FLAGS="-Xfrontend -debug-time-expression-type-checking" | grep -Ei '^\d+\.\d+ms\t/.+$' | sort -r

What did you expect to happen?

I found that many of the most expensive expressions to typecheck were from this repo:
https://github.com/GetStream/stream-chat-swift/blob/develop/Sources/StreamChat/Models/Attachments/ChatMessageImageAttachment.swift#L128
and
https://github.com/GetStream/stream-chat-swift/blob/develop/Sources/StreamChat/Models/Attachments/ChatMessageImageAttachment.swift#L131
took 80ms and 60ms respectively on my laptop (2021 M1). If this was written without the ?? it would likely take 1-2ms.

https://github.com/GetStream/stream-chat-swift/blob/develop/Sources/StreamChatUI/StreamNuke/Internal/ImageRequestKeys.swift#L50
took 32ms

These were the most expensive expressions, but I encourage you to run with the -debug-time-expression-type-checking on the framework to see other locations that are taking a while

GetStream Environment

**GetStream Chat version: 4.63.0
**GetStream Chat frameworks: StreamChat
**iOS version: 18
**Swift version: 6
**Xcode version: 16
**Device: iOS Sim

Additional context

https://danielchasehooper.com/posts/why-swift-is-slow/

[testableapple]

Hi @pm-dev, thank you very much for investigating this and opening the issue. I've added it to our backlog for further investigation. I can't give an ETA for now, but we'll share an update once we start working on it.

Best,
Alexey

[nuno-vieira]

This is now improved in the latest release 👍

Thank you for the report!