Bump macOS minimum deployment target to 10.15

[calvincestari]

This PR is a DRAFT:

• TODO: validation test for nil URLSessionTask.sendRequest return

This change is in preparation for being able to target SQLite.swift version 0.13.0 which requires a minimum of macOS 10.15.

Deprecations as a result of dropping 10.14:

• Breaking: URLSessionTask.init is no longer available so URLSessionTask.sendRequest now returns an optional task with nil being returned when the request could not be sent.

Closes #1868

[calvincestari]

This logic loses the .unspecified (default) behaviour but I think it's better now that we take action based only on the return. We don't gather any error because it was not being logged before and I don't see any good way in this module to output it in a way that is actually useful to a production app.

SecTrustEvaluateWithError(:,:) is the synchronous replacement of the deprecated SecTrustEvaluate(:,:). It is now a simple boolean return.

[calvincestari]

The result was not being used here so we don't store it either with the new call. Again, no error was being reported perviously.

SecTrustEvaluateWithError(:,:) is the synchronous replacement of the deprecated SecTrustEvaluate(:,:). It is now a simple boolean return.

[calvincestari]

This is on hold while #1943 is evaluated.

[calvincestari]

I'm closing this PR since #1943 has been accepted. I debated pulling 1df7341 into #1940 but since all apps implementing apollo-ios must support iOS 12 there is no real need to break behaviour that existing users might be relying on; empty task vs. nil task.

[ghost]

@calvincestari My company's app has iOS 14 as its deployment target, so it's getting a deprecation warning on return URLSessionTask(). It sounds like you can't remove this because iOS 12, but would it be possible to use alternate code for higher iOS versions? I'd be happy to raise a PR if that would be helpful.

[calvincestari]

Hi @OrindaCoder 👋🏻 - correct, we still support iOS 12 which is why the code still uses that deprecated URLSessionTask initializer. We intend to keep iOS 12 as the minimum for the upcoming 1.0 release but 2.0 will certainly bump that to iOS 13 or higher; see details in our Roadmap.

The solution here could be to simply merge the changes in 1df7341 into main as I mentioned above. We're still in 0.x releases so making that kind of breaking change now is somewhat acceptable. If you have an alternate solution though please feel free to submit a PR and we can certainly review and discuss.

[ghost]

@calvincestari I will wait for a future version of Apollo that fixes this warning. Thanks for all the work you do!