operators: add fromAsync, fromThrowingAsync, fromAsyncSequence

[twittemb]

This PR bridges structured concurrency with Combine by adding:

• Publishers.fromAsync(): wraps an async function call into an AnyPublisher<Output, Never>
• Publishers.fromThrowingAsync(): wraps a throwing async function call into an AnyPublisher<Output, Error>
• Publishers.fromAsyncSequence(): wraps an async sequence into an AnyPublisher<Output, Error>

The CI has been adapted to allow the usage of Xcode 13/Swift 5.5.

The SPM section has been removed since xcodebuild can now run swift packages (no Xcode project generate needed).

[codecov]

Codecov Report

Merging #106 (359d0fd) into main (fc3e405) will decrease coverage by 2.02%.
The diff coverage is n/a.

❗ Current head 359d0fd differs from pull request most recent head 52c52be. Consider uploading reports for the commit 52c52be to get more accurate results

@@            Coverage Diff             @@
##             main     #106      +/-   ##
==========================================
- Coverage   97.23%   95.21%   -2.03%     
==========================================
  Files          62       60       -2     
  Lines        3323     3236      -87     
==========================================
- Hits         3231     3081     -150     
- Misses         92      155      +63     

Impacted Files	Coverage Δ
Sources/Operators/SetOutputType.swift	50.00% <0.00%> (-50.00%)	⬇️
Sources/Operators/IgnoreOutputSetOutputType.swift	50.00% <0.00%> (-50.00%)	⬇️
Tests/OptionalTests.swift	94.44% <0.00%> (-5.56%)	⬇️
Sources/Models/Event.swift	47.36% <0.00%> (-5.27%)	⬇️
Sources/Common/Sink.swift	50.00% <0.00%> (-5.00%)	⬇️
Tests/FlatMapBatchesTests.swift	95.34% <0.00%> (-4.66%)	⬇️
Tests/PrefixDurationTests.swift	95.34% <0.00%> (-4.66%)	⬇️
Sources/Common/DemandBuffer.swift	96.15% <0.00%> (-3.85%)	⬇️
Tests/DematerializeTests.swift	93.75% <0.00%> (-3.75%)	⬇️
Tests/PartitionTests.swift	96.29% <0.00%> (-3.71%)	⬇️
... and 19 more

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[twittemb]

@freak4pc the code coverage does not seem happy, but I don't know why. The new code has a 100% coverage but the overall percentage seems to be lower than before.Do you know why ? (it's like that unit tests code coverage is taken into account)

[twittemb]

Hi @freak4pc, do you have an idea of what's going on with the code
coverage ?

Do we want to go forward with this async/await -> Combine bridge ?

[markst]

is there an update on this?

[markst]

I believe this can be:

#if compiler(>=5.5) && canImport(_Concurrency)

rather than forcing iOS15

https://www.swiftbysundell.com/special/swift-concurrency-backward-compatibility/

[markst]

Seems .subscribe(on: RunLoop.main) has no effect:

Publishers.fromThrowingAsync(priority: TaskPriority.background, { () -> [EventEntity] in
    let result = try await self.useCase.invoke(forceRefresh: true)
    return result
})
.subscribe(on: RunLoop.main)
.eraseToAnyPublisher()

The asyncThrowingFunction is called on whatever thread the publisher was created from.

[RomanPodymov]

I think you should not commit this file.