Add support for Swift package manager

[keshav-space]

• Resolves Add support for Swift PM #2657

Tasks

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  Run tests locally to check for errors.
• Commits are in uniquely-named feature branch and has no merge conflicts 📁
• Updated documentation pages (if applicable)
• Updated CHANGELOG.rst (if applicable)

[pombredanne]

Thanks! here are a few feedbacks for you consideration

There are likely a few extra things to consider:

• .package.resolved files like in https://github.com/stripe/stripe-ios/blob/ec051a63435807b6c2ab7fbd6efd35f1173325b9/.package.resolved#L2 are created when using only XCode.
• there may be some older legacy format that look like this for the version 1 https://github.com/fastlane/fastlane/blob/806c80c39754034c3dfcdade6beb51bb55c7f3b1/Package.resolved#L2
• and also version 3 https://github.com/Brightify/Cuckoo/blob/b1ff0383512f0ab954e673718098c6c68bdf57b1/.package.resolved#L122C1-L122C16 from xcode?

Unrelated this https://github.com/tuist/tuist/tree/25d90e3a3d613caf6a740a03ea4d195a685a0feb/fixtures/app_with_spm_dependencies/Tuist has some interesting things:

• a workspace
• development dependencies (they cannot be tagged as such anywhere in Swift syntax)

[pombredanne]

Add namespace

[keshav-space]

@pombredanne We don't have a namespace for the top-level package in the Package.swift manifest.

[pombredanne]

ok, how does this look like when installed?
Is there any trace of where it came from?
https://github.com/mapbox/mapbox-maps-ios/blob/main/Package.swift has some possible base URL. BUT when I see https://github.com/map-ir/mapir-ios-maps-sdk/blob/cfca260d03ab8f0d1889795ec012adae1d3bfbd8/Package.swift#L20 or https://github.com/mapbox/mapbox-navigation-ios/blob/b9c235e665ea2d3b7cd096e9c6128e97c1d4f00c/Package.swift#L27 it is clear that the actual name is one thing and the "package name" is another thing and seem to be resolved only when interpreting a Package.swift for dependencies.

So IMHO we cannot get that actual correct PURL name short of matching or have this used as a dependency. Just create a follow up issue for this so we can address it later.

[keshav-space]

ok, how does this look like when installed?
Is there any trace of where it came from?

Yes, we can trace the source of an already installed package from the .build directory.

Tracking this issue here #3793

The PURL for a Swift package depends on where the package is hosted, and given that Package.swift does not contain the repository URL for the top-level package, it is not possible to infer the correct PURL for the top-level package solely from the Package.swift manifest.
We can use https://swiftpackageindex.com/ to get the correct PURL, but this may not work for all packages since Swift Package Index is not authoritative in nature, i.e. a Swift package may exist, and the author may choose not to add their package to Swift Package Index. https://swiftpackageindex.com/add-a-package

[keshav-space]

Thanks @pombredanne, addressed all your feedback.

[pombredanne]

All good. Please merge.