Surface specific XPC & login item errors

[quanganhdo]

Required:

Task/Issue URL: https://app.asana.com/0/72649045549333/1207013105069620/f
iOS PR:duckduckgo/iOS#2872
macOS PR: https://github.com/duckduckgo/macos-browser/pull/2773
What kind of version bump will this require?: Minor

Optional:

Tech Design URL:
CC:

Description:

Steps to test this PR:

1. See platform-specific PRs

OS Testing:

• iOS 14
• iOS 15
• iOS 16
• macOS 10.15
• macOS 11
• macOS 12

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Internal references:

Software Engineering Expectations
Technical Design Template

[diegoreymendez]

Added some comments as I think there's some space for developer quality-of-life improvements.

[diegoreymendez]

This forces all errors that are "known" to be defined in BSK which seems unnecessarily restrictive.

Why instead not just make the error adhere to Codable and store that in NetworkProtectionKnownFailureStore.

Then the VPN app can decide what errors are worth passing over IPC, but at least we don't have to add errors that are macOS specific to BSK.

[quanganhdo]

Why instead not just make the error adhere to Codable and store that in NetworkProtectionKnownFailureStore.

It's tricky as we need a concrete type to decode the error; and that type needs to be passed around in different ways (e.g. as part of XPCClientInterface, distributed notification object).

To keep it simple, I've moved the custom handling code for TunnelError outside of the initializer and instead made it so that an error conforming to InternalErrorWrapping can expose its internal error. That way we can keep specific errors outside of BSK.

[diegoreymendez]

Understood.

That said, I do think that instead of encoding domain, code and localizedDescription, we should turn this into a Codable enum. See this comment for context.

[diegoreymendez]

Added one request for a change.

[diegoreymendez]

Understood.

That said, I do think that instead of encoding domain, code and localizedDescription, we should turn this into a Codable enum. See this comment for context.