deprecate name attrobute on package dependencies

motivation: follow on work to the change in 5.5 that _allows_ users to not specify a name on the dependency, this soft-deprecates the ability to do so

changes:
* emit a deprecation warning when using the name attribute on a dependency (in the manifest)
* refactor the depedency::name attribute to "deprecatedName" to reflect the fact it was deprecated and prevert too much downstream logic
* cleanup the internal API
* cleanup and add tests

Author: tomerd

Package.swift

@@ -15,7 +15,7 @@ import class Foundation.ProcessInfo
 
 
 /** SwiftPMDataModel is the subset of SwiftPM product that includes just its data model.
-This allowis some clients (such as IDEs) that use SwiftPM's data model but not its build system
+This allows some clients (such as IDEs) that use SwiftPM's data model but not its build system
 to not have to depend on SwiftDriver, SwiftLLBuild, etc. We should probably have better names here,
 though that could break some clients.
 */
@@ -33,7 +33,7 @@ let swiftPMDataModelProduct = (
     ]
 )
 
-/** The `libSwiftPM` set of interfaces to programatically work with Swift
+/** The `libSwiftPM` set of interfaces to programmatically work with Swift
  packages.  `libSwiftPM` includes all of the SwiftPM code except the
  command line tools, while `libSwiftPMDataModel` includes only the data model.
 

Sources/Commands/Describe.swift

@@ -100,16 +100,16 @@ fileprivate struct DescribedPackage: Encodable {
 
     /// Represents a package dependency for the sole purpose of generating a description.
     enum DescribedPackageDependency: Encodable {
-        case fileSystem(name: String?, path: AbsolutePath)
-        case sourceControl(name: String?, location: String, requirement: PackageDependency.SourceControl.Requirement)
+        case fileSystem(path: AbsolutePath)
+        case sourceControl(location: String, requirement: PackageDependency.SourceControl.Requirement)
         case registry(identity: PackageIdentity, requirement: PackageDependency.Registry.Requirement)
 
         init(from dependency: PackageDependency) {
             switch dependency {
             case .fileSystem(let settings):
-                self = .fileSystem(name: dependency.explicitNameForTargetDependencyResolutionOnly, path: settings.path)
+                self = .fileSystem(path: settings.path)
             case .sourceControl(let settings):
-                self = .sourceControl(name: dependency.explicitNameForTargetDependencyResolutionOnly, location: settings.location, requirement: settings.requirement)
+                self = .sourceControl(location: settings.location, requirement: settings.requirement)
             case .registry(let settings):
                 self = .registry(identity: settings.identity, requirement: settings.requirement)
             }

Sources/PackageDescription/PackageDependency.swift

@@ -225,7 +225,7 @@ extension Package.Dependency {
     /// - Parameters:
     ///     - url: The valid Git URL of the package.
     ///     - branch: A dependency requirement. See static methods on `Package.Dependency.Requirement` for available options.
-    @available(_PackageDescription, introduced: 999)
+    @available(_PackageDescription, introduced: 5.5)
     public static func package(
         url: String,
         branch: String
@@ -257,7 +257,7 @@ extension Package.Dependency {
     /// - Parameters:
     ///     - url: The valid Git URL of the package.
     ///     - revision: A dependency requirement. See static methods on `Package.Dependency.Requirement` for available options.
-    @available(_PackageDescription, introduced: 999)
+    @available(_PackageDescription, introduced: 5.5)
     public static func package(
         url: String,
         revision: String

Sources/PackageGraph/PackageGraph+Loading.swift

@@ -423,7 +423,7 @@ private func createResolvedPackages(
                 // explicitly reference the package containing the product, or for the product, package and
                 // dependency to share the same name. We don't check this in manifest loading for root-packages so
                 // we can provide a more detailed diagnostic here.
-                if packageBuilder.package.manifest.toolsVersion >= .v5_2 && productRef.package == nil{
+                if packageBuilder.package.manifest.toolsVersion >= .v5_2 && productRef.package == nil {
                     let referencedPackageIdentity = product.packageBuilder.package.identity
                     guard let referencedPackageDependency = (packageBuilder.package.manifest.dependencies.first { package in
                         return package.identity == referencedPackageIdentity
@@ -435,7 +435,7 @@ private func createResolvedPackages(
                         let error = PackageGraphError.productDependencyMissingPackage(
                             productName: productRef.name,
                             targetName: targetBuilder.target.name,
-                            packageDependency: referencedPackageDependency
+                            packageIdentifier: referencedPackageName
                         )
                         diagnostics.emit(error, location: package.diagnosticLocation)
                     }

Sources/PackageGraph/PackageGraph.swift

@@ -34,7 +34,7 @@ enum PackageGraphError: Swift.Error {
     case productDependencyMissingPackage(
         productName: String,
         targetName: String,
-        packageDependency: PackageDependency
+        packageIdentifier: String
     )
 
     /// A product was found in multiple packages.
@@ -213,12 +213,12 @@ extension PackageGraphError: CustomStringConvertible {
         case .productDependencyMissingPackage(
                 let productName,
                 let targetName,
-                let packageDependency
+                let packageIdentifier
             ):
 
             let solution = """
             reference the package in the target dependency with '.product(name: "\(productName)", package: \
-            "\(packageDependency.nameForTargetDependencyResolutionOnly)")'
+            "\(packageIdentifier)")'
             """
 
             return "dependency '\(productName)' in target '\(targetName)' requires explicit declaration; \(solution)"
@@ -229,6 +229,7 @@ extension PackageGraphError: CustomStringConvertible {
     }
 }
 
+/*
 fileprivate extension PackageDependency {
     func swiftRepresentation(overridingName: String? = nil) -> String {
         var parameters: [String] = []
@@ -278,3 +279,4 @@ fileprivate extension PackageDependency {
         return swiftRepresentation
     }
 }
+ */