Package.swift 和 Xcode 11 项目，如何同时使用 Carthage 和 SPM？

Question

I feel caught between the Carthage world and the Swift Package Manager (SPM) world, like being stuck in purgatory.

I'm developing a Swift library/SDK , and up until now, I've been using Carthage for dependencies. But since SPM finally works with iOS, I feel it would be great for people who want to use this library to be able to include it via SPM.

However, I've hit a wall. One of my dependencies, namely BitcoinKit works with Carthage but SPM support is broken.

In order to distribute my library, I need to have a Package.swift file, and some other critteria (README, source files in Sources , and tests in Tests ). I also need to declare my dependencies in said Package.swift file, so that SPM recursivley can resolve all dependencies (when people install my library via SPM). Here's where I get stuck...

Since I'm still using Carthage I need a Xcode Project file to set up this Carthage dependency. But now my source files cannot import the SPM dependencies. They aren't found. Seems like I MUST include the SPM package dependencies using Xcode and Add Package Dependency feature (Apple doc here) . This is not what I want right, I want my Package.swift file to declare the same versions of the SPM packages my library uses. To make it clear, this problem arises due to the fact that I need a Xcode project, due to Carthage.

So I thought maybe I could build BitcoinKit with Carthage (as I'm doing now), and include the built binary ( .Carthage/Build/iOS/BitcoinKit.framework ) my library, referencing it in Package.swift , but that does not work since SPM does not (yet?) support binaries ( relevant Swift Forum Thread ).

So what are my options?

1) Wait until someone smart fixes the broken SPM support in BitcoinKit (I've tried myself and failed), and then remove my Xcode project file and complete the transition of to only SPM and for now stick with Carthage...

2) Try to use SPM packages internally in my library installed through Xcode Add Package Dependency feature and manually sync those versions with the ones I declare in my Package.swift . Will that even work? Ugh, terrible solution anyway.

3) Hope to include BitcoinKit.framework built through Carthage as a binary when SPM supports it? When? Might take a while?

4) BitcoinKit also works with Cocoapods, but I guess that gets me nowhere, even worse actually, since Cocoapods creates a .xcworkspace file.

5) Wait until Apple hopefully (does anyone know if there are any plans?) changes so that we include Swift Packages via Package.swift file even when used together with an Xcode project file? That we I could keep on using Bitcoinkit via Carthage and only declare my SPM packages in one place and I guess SPM/Xcode/Swift would be responsible for integrating the dependencies into my Xcode project, but updated and managed through the Package.swift file...?

6) Any other alternative, real solution?

Answer 1

Without looking into the whole 'making bitcoinkit work with SPM' bit I think the 'linking a carthage prebuilt binary' idea sounds best as an interim solution at the very least.

It's not possible to link a binary in the package manifest (yet) but you can link it when you're building: When building an SPM package from the command line using swift build you can link the binary using -Xswiftc or -Xlinker to pass the args -F path/to/bitcoinkit if you're linking a framework. Keep in mind each argument must have a cross argument flag before it. When building in Xcode you should be able to solve it with an .xcconfig with the contents:

FRAMEWORK_SEARCH_PATHS = path/to/bitcoinkit

You may have to tweak it a bit but I imagine this should work, worst case having a separate .xcodeproj generated by swift package generate-xcodeproj --xcconfig-overrides myconfig.xcconfig .

Answer 2

There is a WalletExample in yenom/BitcoinKit on GitHub. It comes with a workspace and project.

I was able to include yenom/BitcoinKit with SPM in my Package.swift and I don't use any projects/workspaces.