adding firebase-ios-sdk to Xcode Swift Packages, as well as depending on it in a local Swift Package causes packages to fail to resolve consistently.

[jondwillis]

[REQUIRED] Step 1: Describe your environment

• Xcode version: 12.3
• Firebase SDK version: 7.4.0 (also affects at least 7.3.x)
• Installation method: Swift Package Manager
• Firebase Component: Analytics, FirebaseCrashlytics, perhaps all.

[REQUIRED] Step 2: Describe the problem

Steps to reproduce:

(See example project linked at the bottom)

adding firebase-ios-sdk to Xcode Swift Packages, as well as depending on it in a local Swift Package causes packages to fail to resolve consistently.

The Results:

artifact of binary target 'FirebaseAnalytics' failed extraction: The operation couldn’t be completed. (TSCBasic.StringError error 1.)
artifact of binary target 'GoogleAppMeasurement' failed extraction: The operation couldn’t be completed. (TSCBasic.StringError error 1.)

The (Workaround) Solution:

Some combination of closing Xcode, Resetting Package Cache, and Updating Package Dependencies can resolve it temporarily.

Relevant Code:

https://github.com/jondwillis/FirebaseSPMBug

[paulb777]

Thanks for the report.

It's almost certainly a Swift Package Manager bug and I recommend reporting there also. It looks similar to https://forums.swift.org/t/problem-in-xcode-project-to-get-all-dependencies/42287.

[jondwillis]

@paulb777 Thanks, I agree. I added to the thread that you linked to. Overall the SPM<>Xcode integration seems quite buggy.

[paulb777]

Thanks @jondwillis. I would add the distinction about SPM <> Xcode integration bugginess specifically for binary packages. The source package integration has been more stable.

[paulb777]

@jondwillis Does Xcode 12.5 address this?

[jondwillis]

@paulb777 ...sort of! ... with some changes, thanks to improved Xcode-SPM error messaging.

For context, this was my local swift package's Package.swift:

...
    dependencies: [
        .package(url: "https://github.com/Quick/Quick.git", from: "3.0.0"),
        .package(url: "https://github.com/Quick/Nimble.git", from: "9.0.0"),
        .package(url: "https://github.com/firebase/firebase-ios-sdk", from: "7.4.0"),
    ],
    targets: [
        .target(
            name: "Analytics",
            dependencies: [
                .product(name: "FirebaseAnalytics", package: "Firebase"),
                .product(name: "FirebaseCrashlytics", package: "Firebase"),
            ]),
            ...

Without any changes to my example project in Xcode 12.5 beta, I received the following error when resolving packages:

unknown package 'Firebase' in dependencies of target 'Analytics'; valid packages are: 'Quick', 'Nimble', 'firebase-ios-sdk'

I decided to bump to version to 7.6.0 at this time, and remove the firebase dependency from my project's Swift packages. Then I tried changing the local dependency's dependencies package name to firebase-ios-sdk, e.g.:

.product(name: "FirebaseCrashlytics", package: "firebase-ios-sdk"),

Which allowed the dependency's dependency to resolve. However, when re-adding Firebase to my project's Swift package, I got another error:

product dependency 'FirebaseAnalytics' in package 'firebase-ios-sdk' not found

Seems circular! That then led me to the solution, removing the project's Firebase dependency again, then adding an explicit name to my local dependency's product dependencies, and re-adding my projects Firebase dependency (including in case the order here matters):

...
dependencies: [
        .package(url: "https://github.com/Quick/Quick.git", from: "3.0.0"),
        .package(url: "https://github.com/Quick/Nimble.git", from: "9.0.0"),
        .package(name: "Firebase", url: "https://github.com/firebase/firebase-ios-sdk", from: "7.6.0"),
    ],
    targets: [
        .target(
            name: "Analytics",
            dependencies: [
                .product(name: "FirebaseAnalytics", package: "Firebase"),
                .product(name: "FirebaseCrashlytics", package: "Firebase"),
            ]),
...

I updated my toy project repo with the working solution.

⚠️ for future folks stumbling upon this, I did notice while going back and replaying these steps for this write-up, the previous broken behavior appeared again unexpectedly, so maybe this needs to all happen in a really specific order, or can still occur transiently.

[paulb777]

@jondwillis Thanks for sharing your journey and solution. I'm going to close since the sporadic functionality is almost certainly a Swift Package Manager and not specifically the Firebase implementation.