[SwiftRefactor] PackageManifest: Remove identity from FileSystem and SourceControl

Both types are identified by their path and location respectively.

Author: xedin

Sources/SwiftRefactor/PackageManifest/AddPackageDependency.swift

@@ -128,9 +128,9 @@ fileprivate extension PackageDependency {
   var identifier: String {
     switch self {
     case .sourceControl(let info):
-      return info.identity
+      return info.location
     case .fileSystem(let info):
-      return info.identity
+      return info.path
     case .registry(let info):
       return info.identity
     }

Sources/SwiftRefactor/PackageManifest/AddPackageTarget.swift

@@ -349,7 +349,6 @@ fileprivate extension PackageDependency {
   static func swiftSyntax(from version: String) -> PackageDependency {
     return .sourceControl(
       .init(
-        identity: "swift-syntax",
         location: swiftSyntaxURL,
         requirement: .rangeFrom(version)
       )

Sources/SwiftRefactor/PackageManifest/PackageDependency.swift

@@ -22,18 +22,15 @@ public enum PackageDependency: Sendable {
   case registry(Registry)
 
   public struct FileSystem: Sendable {
-    public let identity: String
     public let nameForTargetDependencyResolutionOnly: String?
     public let path: String
   }
 
   public struct SourceControl: Sendable {
-    public let identity: String
     public let location: String
     public let requirement: Requirement
 
-    public init(identity: String, location: String, requirement: Requirement) {
-      self.identity = identity
+    public init(location: String, requirement: Requirement) {
       self.location = location
       self.requirement = requirement
     }

Tests/SwiftRefactorTest/ManifestEditTests.swift

@@ -23,7 +23,6 @@ final class ManifestEditTests: XCTestCase {
 
   static let swiftSystemPackageDependency: PackageDependency = .sourceControl(
     .init(
-      identity: "swift-system",
       location: swiftSystemURL,
       requirement: .branch("main")
     )
@@ -54,7 +53,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .branch("main")
           )
@@ -88,7 +86,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .exact("510.0.0")
           )
@@ -120,7 +117,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .exact("510.0.0")
           )
@@ -154,7 +150,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .exact("510.0.0")
           )
@@ -179,7 +174,7 @@ final class ManifestEditTests: XCTestCase {
       )
     ) { (error: any Error) in
       guard let error = error as? ManifestEditError,
-        case .existingDependency("swift-system") = error
+        case .existingDependency("https://github.com/apple/swift-system.git") = error
       else {
         XCTFail("unexpected error thrown: \(error)")
         return
@@ -212,7 +207,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .rangeFrom("510.0.0")
           )
@@ -241,7 +235,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .rangeFrom("510.0.0")
           )
@@ -268,7 +261,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .rangeFrom("510.0.0")
           )
@@ -299,7 +291,6 @@ final class ManifestEditTests: XCTestCase {
       context: .init(
         dependency: .sourceControl(
           .init(
-            identity: "swift-system",
             location: Self.swiftSystemURL,
             requirement: .range(lowerBound: "508.0.0", upperBound: "510.0.0")
           )