Export PackageCollectionsSigning as library

We will add signing to [the set of collections tools](https://github.com/apple/swift-package-collection-generator), and for that we'd need `PackageCollectionsSigning`.

Author: yim-lee

Package.swift

@@ -8,10 +8,10 @@
 
  See http://swift.org/LICENSE.txt for license information
  See http://swift.org/CONTRIBUTORS.txt for Swift project authors
-*/
+ */
 
-import PackageDescription
 import class Foundation.ProcessInfo
+import PackageDescription
 
 // We default to a 10.10 minimum deployment target for clients of libSwiftPM,
 // but allow overriding it when building for a toolchain.
@@ -46,7 +46,7 @@ let package = Package(
                 "PackageGraph",
                 "Build",
                 "Xcodeproj",
-                "Workspace"
+                "Workspace",
             ]
         ),
         .library(
@@ -62,7 +62,7 @@ let package = Package(
                 "PackageGraph",
                 "Build",
                 "Xcodeproj",
-                "Workspace"
+                "Workspace",
             ]
         ),
         .library(
@@ -76,7 +76,7 @@ let package = Package(
                 "PackageLoading",
                 "PackageGraph",
                 "Xcodeproj",
-                "Workspace"
+                "Workspace",
             ]
         ),
 
@@ -90,11 +90,21 @@ let package = Package(
             type: .dynamic,
             targets: ["PackageDescription"]
         ),
-        
+
         .library(
             name: "PackageCollectionsModel",
             targets: ["PackageCollectionsModel"]
         ),
+
+        .library(
+            name: "SwiftPMPackageCollections",
+            targets: [
+                "PackageCollections",
+                "PackageCollectionsModel",
+                "PackageCollectionsSigning",
+                "PackageModel",
+            ]
+        ),
     ],
     targets: [
         // The `PackageDescription` targets define the API which is available to
@@ -106,195 +116,238 @@ let package = Package(
             name: "PackageDescription",
             swiftSettings: [
                 .define("PACKAGE_DESCRIPTION_4_2"),
-            ]),
+            ]
+        ),
 
         // MARK: SwiftPM specific support libraries
 
         .target(
             name: "Basics",
-            dependencies: ["SwiftToolsSupport-auto"]),
+            dependencies: ["SwiftToolsSupport-auto"]
+        ),
 
         .target(
             /** The llbuild manifest model */
             name: "LLBuildManifest",
-            dependencies: ["SwiftToolsSupport-auto", "Basics"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics"]
+        ),
 
         .target(
             /** Source control operations */
             name: "SourceControl",
-            dependencies: ["SwiftToolsSupport-auto", "Basics"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics"]
+        ),
         .target(
             /** Shim for llbuild library */
             name: "SPMLLBuild",
-            dependencies: ["SwiftToolsSupport-auto", "Basics"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics"]
+        ),
 
         // MARK: Project Model
 
         .target(
             /** Primitive Package model objects */
             name: "PackageModel",
-            dependencies: ["SwiftToolsSupport-auto", "Basics"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics"]
+        ),
         .target(
             /** Package model conventions and loading support */
             name: "PackageLoading",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageModel", "SourceControl"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageModel", "SourceControl"]
+        ),
 
         // MARK: Package Dependency Resolution
 
         .target(
             /** Data structures and support for complete package graphs */
             name: "PackageGraph",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageLoading", "PackageModel", "SourceControl"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageLoading", "PackageModel", "SourceControl"]
+        ),
 
         // MARK: Package Collections
-        
+
         .target(
             /** Package collections models */
             name: "PackageCollectionsModel",
-            dependencies: []),
-        
+            dependencies: []
+        ),
+
         .target(
-             /** Package collections signing */
-             name: "PackageCollectionsSigning",
-             dependencies: ["PackageCollectionsModel", "Crypto", "Basics"]),
+            /** Package collections signing */
+            name: "PackageCollectionsSigning",
+            dependencies: ["PackageCollectionsModel", "Crypto", "Basics"]
+        ),
 
         .target(
             /** Data structures and support for package collections */
             name: "PackageCollections",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageModel", "SourceControl", "PackageCollectionsModel"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageModel", "SourceControl", "PackageCollectionsModel"]
+        ),
 
         // MARK: Package Manager Functionality
 
         .target(
             /** Builds Modules and Products */
             name: "SPMBuildCore",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageGraph"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageGraph"]
+        ),
         .target(
             /** Builds Modules and Products */
             name: "Build",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "SPMBuildCore", "PackageGraph", "LLBuildManifest", "SwiftDriver", "SPMLLBuild"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "SPMBuildCore", "PackageGraph", "LLBuildManifest", "SwiftDriver", "SPMLLBuild"]
+        ),
         .target(
             /** Support for building using Xcode's build system */
             name: "XCBuildSupport",
-            dependencies: ["SPMBuildCore", "PackageGraph"]),
+            dependencies: ["SPMBuildCore", "PackageGraph"]
+        ),
 
         .target(
             /** Generates Xcode projects */
             name: "Xcodeproj",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageGraph"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "PackageGraph"]
+        ),
         .target(
             /** High level functionality */
             name: "Workspace",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "SPMBuildCore", "PackageGraph", "PackageModel", "SourceControl", "Xcodeproj"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "SPMBuildCore", "PackageGraph", "PackageModel", "SourceControl", "Xcodeproj"]
+        ),
 
         // MARK: Commands
 
         .target(
             /** High-level commands */
             name: "Commands",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "Build", "PackageGraph", "SourceControl", "Xcodeproj", "Workspace", "XCBuildSupport", "ArgumentParser", "PackageCollections"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "Build", "PackageGraph", "SourceControl", "Xcodeproj", "Workspace", "XCBuildSupport", "ArgumentParser", "PackageCollections"]
+        ),
         .target(
             /** The main executable provided by SwiftPM */
             name: "swift-package",
-            dependencies: ["Commands"]),
+            dependencies: ["Commands"]
+        ),
         .target(
             /** Builds packages */
             name: "swift-build",
-            dependencies: ["Commands"]),
+            dependencies: ["Commands"]
+        ),
         .target(
             /** Runs package tests */
             name: "swift-test",
-            dependencies: ["Commands"]),
+            dependencies: ["Commands"]
+        ),
         .target(
             /** Runs an executable product */
             name: "swift-run",
-            dependencies: ["Commands"]),
+            dependencies: ["Commands"]
+        ),
         .target(
             /** Interacts with package collections */
             name: "swift-package-collection",
-            dependencies: ["Commands"]),
+            dependencies: ["Commands"]
+        ),
         .target(
             /** Shim tool to find test names on OS X */
             name: "swiftpm-xctest-helper",
             dependencies: [],
             linkerSettings: [
                 .unsafeFlags(["-Xlinker", "-rpath", "-Xlinker", "@executable_path/../../../lib/swift/macosx"], .when(platforms: [.macOS])),
-            ]),
+            ]
+        ),
 
         // MARK: Additional Test Dependencies
 
         .target(
             /** SwiftPM test support library */
             name: "SPMTestSupport",
-            dependencies: ["SwiftToolsSupport-auto", "Basics", "TSCTestSupport", "PackageGraph", "PackageLoading", "SourceControl", "Workspace", "Xcodeproj", "XCBuildSupport"]),
+            dependencies: ["SwiftToolsSupport-auto", "Basics", "TSCTestSupport", "PackageGraph", "PackageLoading", "SourceControl", "Workspace", "Xcodeproj", "XCBuildSupport"]
+        ),
 
         // MARK: SwiftPM tests
 
         .testTarget(
             name: "BasicsTests",
-            dependencies: ["Basics", "SPMTestSupport"]),
+            dependencies: ["Basics", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "BuildTests",
-            dependencies: ["Build", "SPMTestSupport"]),
+            dependencies: ["Build", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "CommandsTests",
-            dependencies: ["swift-build", "swift-package", "swift-test", "swift-run", "Commands", "Workspace", "SPMTestSupport"]),
+            dependencies: ["swift-build", "swift-package", "swift-test", "swift-run", "Commands", "Workspace", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "WorkspaceTests",
-            dependencies: ["Workspace", "SPMTestSupport"]),
+            dependencies: ["Workspace", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "FunctionalTests",
-            dependencies: ["swift-build", "swift-package", "swift-test", "PackageModel", "SPMTestSupport"]),
+            dependencies: ["swift-build", "swift-package", "swift-test", "PackageModel", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "FunctionalPerformanceTests",
-            dependencies: ["swift-build", "swift-package", "swift-test", "SPMTestSupport"]),
+            dependencies: ["swift-build", "swift-package", "swift-test", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageDescription4Tests",
-            dependencies: ["PackageDescription"]),
+            dependencies: ["PackageDescription"]
+        ),
         .testTarget(
             name: "SPMBuildCoreTests",
-            dependencies: ["SPMBuildCore", "SPMTestSupport"]),
+            dependencies: ["SPMBuildCore", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageLoadingTests",
             dependencies: ["PackageLoading", "SPMTestSupport"],
-            exclude: ["Inputs"]),
+            exclude: ["Inputs"]
+        ),
         .testTarget(
             name: "PackageLoadingPerformanceTests",
-            dependencies: ["PackageLoading", "SPMTestSupport"]),
+            dependencies: ["PackageLoading", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageModelTests",
-            dependencies: ["PackageModel", "SPMTestSupport"]),
+            dependencies: ["PackageModel", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageGraphTests",
-            dependencies: ["PackageGraph", "SPMTestSupport"]),
+            dependencies: ["PackageGraph", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageGraphPerformanceTests",
-            dependencies: ["PackageGraph", "SPMTestSupport"]),
+            dependencies: ["PackageGraph", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageCollectionsModelTests",
-            dependencies: ["PackageCollectionsModel"]),
+            dependencies: ["PackageCollectionsModel"]
+        ),
         .testTarget(
             name: "PackageCollectionsSigningTests",
-            dependencies: ["PackageCollectionsSigning", "SPMTestSupport"]),
+            dependencies: ["PackageCollectionsSigning", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "PackageCollectionsTests",
-            dependencies: ["PackageCollections", "SPMTestSupport"]),
+            dependencies: ["PackageCollections", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "SourceControlTests",
-            dependencies: ["SourceControl", "SPMTestSupport"]),
+            dependencies: ["SourceControl", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "XcodeprojTests",
-            dependencies: ["Xcodeproj", "SPMTestSupport"]),
+            dependencies: ["Xcodeproj", "SPMTestSupport"]
+        ),
         .testTarget(
             name: "XCBuildSupportTests",
-            dependencies: ["XCBuildSupport", "SPMTestSupport"]),
+            dependencies: ["XCBuildSupport", "SPMTestSupport"]
+        ),
 
         // Examples (These are built to ensure they stay up to date with the API.)
         .target(
             name: "package-info",
             dependencies: ["PackageModel", "PackageLoading", "PackageGraph", "Workspace"],
             path: "Examples/package-info/Sources/package-info"
-        )
+        ),
     ],
     swiftLanguageVersions: [.v5]
 )