Fix Xcode Swift 5 conversion warning

[AnderGoig]

After the update to Swift 5 the swift_version was deleted from PromisesSwift.podspec (70c337e196c81f795eedb5d7a42cf966f07cdc3d). But now, Xcode keeps showing the "Conversion to Swift 5 is available" warning:

Putting it back will make the warning disappear.

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[AnderGoig]

I signed it!

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CLAs look good, thanks!

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[ghost]

Hi Ander, Thank you for the PR!

Can you provide some more details on how you verified this? Xcode version? Swift version for project?

Also, did you test this with Xcode 10.1 and Swift 4.2 to make sure that specifying s.swift_version = '5.0' doesn't cause any issues for developers who are still using 4.2?

Another option could be to specify s.swift_versions = ['4.2', '5.0'], but may not be needed if swift_version = '5.0' doesn't cause any issues for devs still using 4.2.

Thank you!

[AnderGoig]

Hi @temrich,

You're right, I have tried with Xcode 10.1 and it won't work, I forgot this library still supports 4.2.

Also, specifying s.swift_versions = ['4.2', '5.0'] won't make so much difference, as developers using Swift 4.2, as far as I know, still will have to specify the Swift version in their Podfile's post_install, something like:

post_install do |installer|
    installer.pods_project.targets.each do |target|
        if ['PromisesSwift'].include? target.name
            target.build_configurations.each do |config|
                config.build_settings['SWIFT_VERSION'] = '4.2'
            end
        end
    end
end

So maybe it is not worth it at all, thanks for your help anyway!

[ghost]

Thank you for testing this out! I also think that swift_versions was recently added to CocoaPods, so would probably require developers to update to the latest version (some devs may not be able to do that).

[AnderGoig]

Yes, it was added on 1.7.0 (pretty recently). I'm closing this for now, thanks!

[pxlRider]

Hi, I have same issue when using Firebase which uses this package (through SPM). If looking at Package.swift file at top version is specified as // swift-tools-version:4.2 In file it should probably be swiftLanguageVersions: [.v4, .v4_2, .version("5")] line?