[Workspace] NFC: Handle loading of provided library managed dependencies directly

Instead of going through the ManifestLoader machinery and special
cases in validator let's just produce mainfest directly.

Author: xedin

Sources/PackageLoading/ManifestLoader+Validation.swift

@@ -34,11 +34,6 @@ public struct ManifestValidator {
 
     /// Validate the provided manifest.
     public func validate() -> [Basics.Diagnostic] {
-        // Provided library manifest is synthesized by the package manager.
-        if case .providedLibrary =  self.manifest.packageKind {
-            return []
-        }
-
         var diagnostics = [Basics.Diagnostic]()
 
         diagnostics += self.validateTargets()

Sources/PackageLoading/ManifestLoader.swift

@@ -206,19 +206,6 @@ extension ManifestLoaderProtocol {
         completion: @escaping (Result<Manifest, Error>) -> Void
     ) {
         do {
-            if case .providedLibrary = packageKind {
-                let manifest = try self.loadLibrary(
-                    fileSystem: fileSystem,
-                    packagePath: packagePath,
-                    packageKind: packageKind,
-                    packageIdentity: packageIdentity,
-                    packageLocation: packageLocation,
-                    packageVersion: packageVersion?.version
-                )
-                completion(.success(manifest))
-                return
-            }
-
             // find the manifest path and parse it's tools-version
             let manifestPath = try ManifestLoader.findManifest(packagePath: packagePath, fileSystem: fileSystem, currentToolsVersion: currentToolsVersion)
             let manifestToolsVersion = try ToolsVersionParser.parse(manifestPath: manifestPath, fileSystem: fileSystem)
@@ -279,53 +266,6 @@ extension ManifestLoaderProtocol {
             )
         }
     }
-
-    private func loadLibrary(
-        fileSystem: FileSystem,
-        packagePath: AbsolutePath,
-        packageKind: PackageReference.Kind,
-        packageIdentity: PackageIdentity,
-        packageLocation: String,
-        packageVersion: Version?
-    ) throws -> Manifest {
-        let names = try fileSystem.getDirectoryContents(packagePath).filter {
-            $0.hasSuffix("swiftmodule")
-        }.map {
-            let components = $0.split(separator: ".")
-            return String(components[0])
-        }
-
-        let products: [ProductDescription] = try names.map {
-            try .init(name: $0, type: .library(.automatic), targets: [$0])
-        }
-
-        let targets: [TargetDescription] = try names.map {
-            try .init(
-                name: $0,
-                path: packagePath.pathString,
-                type: .providedLibrary
-            )
-        }
-
-        return .init(
-            displayName: packageIdentity.description,
-            path: packagePath.appending(component: "provided-libraries.json"),
-            packageKind: packageKind,
-            packageLocation: packageLocation,
-            defaultLocalization: nil,
-            platforms: [],
-            version: packageVersion,
-            revision: nil,
-            toolsVersion: .v6_0,
-            pkgConfig: nil,
-            providers: nil,
-            cLanguageStandard: nil,
-            cxxLanguageStandard: nil,
-            swiftLanguageVersions: nil,
-            products: products,
-            targets: targets
-        )
-    }
 }
 
 // MARK: - ManifestLoader

Sources/PackageModel/Manifest/Manifest.swift

@@ -557,3 +557,50 @@ extension Manifest: Encodable {
         try container.encode(self.packageKind, forKey: .packageKind)
     }
 }
+
+extension Manifest {
+    package static func forProvidedLibrary(
+        fileSystem: FileSystem,
+        package: PackageReference,
+        libraryPath: AbsolutePath,
+        version: Version
+    ) throws -> Manifest {
+        let names = try fileSystem.getDirectoryContents(libraryPath).filter {
+            $0.hasSuffix("swiftmodule")
+        }.map {
+            let components = $0.split(separator: ".")
+            return String(components[0])
+        }
+
+        let products: [ProductDescription] = try names.map {
+            try .init(name: $0, type: .library(.automatic), targets: [$0])
+        }
+
+        let targets: [TargetDescription] = try names.map {
+            try .init(
+                name: $0,
+                path: libraryPath.pathString,
+                type: .providedLibrary
+            )
+        }
+
+        return .init(
+            displayName: package.identity.description,
+            path: libraryPath.appending(component: "provided-library.json"),
+            packageKind: package.kind,
+            packageLocation: package.locationString,
+            defaultLocalization: nil,
+            platforms: [],
+            version: version,
+            revision: nil,
+            toolsVersion: .v6_0,
+            pkgConfig: nil,
+            providers: nil,
+            cLanguageStandard: nil,
+            cxxLanguageStandard: nil,
+            swiftLanguageVersions: nil,
+            products: products,
+            targets: targets
+        )
+    }
+}

Sources/Workspace/Workspace+Manifests.swift

@@ -659,9 +659,14 @@ extension Workspace {
         case .registryDownload(let downloadedVersion):
             packageKind = managedDependency.packageRef.kind
             packageVersion = downloadedVersion
-        case .providedLibrary(_, let version):
-            packageKind = managedDependency.packageRef.kind
-            packageVersion = version
+        case .providedLibrary(let path, let version):
+            let manifest: Manifest? = try? .forProvidedLibrary(
+                fileSystem: fileSystem,
+                package: managedDependency.packageRef,
+                libraryPath: path,
+                version: version
+            )
+            return completion(manifest)
         case .custom(let availableVersion, _):
             packageKind = managedDependency.packageRef.kind
             packageVersion = availableVersion