CoreCommands: fix unused `getRootPackageInformation()` result warning

[dschaefer2]

@swift-ci please test

[MaxDesiatov]

Do we have any certainty that this call has no side effects, like calling out to git to check out the package, compiling and loading manifests, or anything else similar to that?

[dschaefer2]

Do we have any certainty that this call has no side effects, like calling out to git to check out the package, compiling and loading manifests, or anything else similar to that?

@valeriyvan can you check this. It's weird this line of code would still be there. We just need to be careful.

[valeriyvan]

Do we have any certainty that this call has no side effects, like calling out to git to check out the package, compiling and loading manifests, or anything else similar to that?

@valeriyvan can you check this. It's weird this line of code would still be there. We just need to be careful.

I don't see any side effects in getRootPackageInformation() itself:

    public func getRootPackageInformation() async throws -> (dependencies: [PackageIdentity: [PackageIdentity]], targets: [PackageIdentity: [String]]) {
        let workspace = try self.getActiveWorkspace()
        let root = try self.getWorkspaceRoot()
        let rootManifests = try await workspace.loadRootManifests(
            packages: root.packages,
            observabilityScope: self.observabilityScope
        )

        var identities = [PackageIdentity: [PackageIdentity]]()
        var targets = [PackageIdentity: [String]]()

        rootManifests.forEach {
            let identity = PackageIdentity(path: $0.key)
            identities[identity] = $0.value.dependencies.map(\.identity)
            targets[identity] = $0.value.targets.map { $0.name.spm_mangledToC99ExtendedIdentifier() }
        }

        return (identities, targets)
    }

[MaxDesiatov]

I don't think that's true. If that function were pure, it wouldn't be async in the first place. await workspace.loadRootManifests(...) in getRootPackageInformation() body is clearly effectful: it's asynchronous and causes manifests loading (potentially compilation of root package's Package.swift before loading too). If the goal is to address the warning, we should ignore the result, but removing this call changes the behavior.

[plemarquand]

I believe ultimately workspace.loadRootManifests calls ManifestLoader.loadAndCacheManifest. Is it possible this call is meant to do the manifest loading work up front?

[MaxDesiatov]

Yes, that's my understanding of it, although I'm not the original author of this code.

[valeriyvan]

If that is true getRootPackageInformation should be renamed.

[valeriyvan]

Changed PR to just discard unused return value.

[dschaefer2]

If that is true getRootPackageInformation should be renamed.

Can't argue with that. :).

[dschaefer2]

@swift-ci please test

[dschaefer2]

@swift-ci please test windows