deprecate name attribute 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

@@ -6,7 +6,7 @@
 
  See http://swift.org/LICENSE.txt for license information
  See http://swift.org/CONTRIBUTORS.txt for Swift project authors
-*/
+ */
 
 import TSCBasic
 import PackageModel
@@ -58,7 +58,7 @@ fileprivate struct DescribedPackage: Encodable {
         self.name = package.manifestName // TODO: rename property to manifestName?
         self.path = package.path.pathString
         self.toolsVersion = "\(package.manifest.toolsVersion.major).\(package.manifest.toolsVersion.minor)"
-            + (package.manifest.toolsVersion.patch == 0 ? "" : ".\(package.manifest.toolsVersion.patch)")
+        + (package.manifest.toolsVersion.patch == 0 ? "" : ".\(package.manifest.toolsVersion.patch)")
         self.dependencies = package.manifest.dependencies.map { DescribedPackageDependency(from: $0) }
         self.defaultLocalization = package.manifest.defaultLocalization
         self.platforms = package.manifest.platforms.map { DescribedPlatformRestriction(from: $0) }
@@ -100,24 +100,23 @@ 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)
             }
         }
 
         private enum CodingKeys: CodingKey {
             case type
-            case name
             case path
             case url
             case requirement
@@ -133,20 +132,17 @@ fileprivate struct DescribedPackage: Encodable {
         public func encode(to encoder: Encoder) throws {
             var container = encoder.container(keyedBy: CodingKeys.self)
             switch self {
-            case .fileSystem(let name, let path):
+            case .fileSystem(let path):
                 try container.encode(Kind.fileSystem, forKey: .type)
-                try container.encode(name, forKey: .name)
                 try container.encode(path, forKey: .path)
-            case .sourceControl(let name, let location, let requirement):
+            case .sourceControl(let location, let requirement):
                 try container.encode(Kind.sourceControl, forKey: .type)
-                try container.encode(name, forKey: .name)
                 try container.encode(location, forKey: .url)
                 try container.encode(requirement, forKey: .requirement)
             case .registry(let identity, let requirement):
                 try container.encode(Kind.registry, forKey: .type)
                 try container.encode(identity, forKey: .identity)
                 try container.encode(requirement, forKey: .requirement)
-
             }
         }
     }
@@ -287,7 +283,7 @@ public struct PlainTextEncoder {
 
         func unkeyedContainer() -> UnkeyedEncodingContainer {
             return PlainTextUnkeyedEncodingContainer(outputStream: outputStream, formattingOptions: formattingOptions, userInfo: userInfo, codingPath: codingPath)
-       }
+        }
 
         func singleValueContainer() -> SingleValueEncodingContainer {
             return TextSingleValueEncodingContainer(outputStream: outputStream, formattingOptions: formattingOptions, userInfo: userInfo, codingPath: codingPath)