Adjust for Swift 5.5 output

Sources/SwiftDependencyUpdaterLibrary/Dependency.swift

@@ -30,7 +30,7 @@ struct Dependency {
     }
 
     static func loadDependencies(from folder: URL) throws -> [Dependency] {
-        let packageDescription = try PackageDescription.loadPackageDescription(from: folder)
+        let packageDescription = try PackageDescriptionFactory.loadPackageDescription(from: folder)
         if packageDescription.dependencies.isEmpty {
             return []
         }

Sources/SwiftDependencyUpdaterLibrary/PackageDescription.swift

@@ -2,7 +2,29 @@ import Foundation
 import Releases
 import ShellOut
 
-struct PackageDependency: Decodable {
+protocol PackageDependency: Decodable {
+
+    var name: String { get }
+    var requirement: DependencyRequirement { get }
+    var url: URL { get }
+
+}
+
+private struct PackageDependencyV54: PackageDependency {
+
+    let name: String
+    let requirement: DependencyRequirement
+    let url: URL
+}
+
+private struct PackageDependencyV55: PackageDependency {
+
+    enum CodingKeys: String, CodingKey {
+        case name = "identity"
+        case requirement
+        case url = "location"
+    }
+
     let name: String
     let requirement: DependencyRequirement
     let url: URL
@@ -68,18 +90,47 @@ enum PackageDescriptionError: Error, Equatable {
     case parsingFailed(String, String)
 }
 
-struct PackageDescription: Decodable {
-    let dependencies: [PackageDependency]
+struct PackageDescriptionV54: PackageDescription {
 
-    static func loadPackageDescription(from folder: URL) throws -> Self {
+    enum CodingKeys: String, CodingKey {
+        case dependenciesArray = "dependencies"
+    }
+
+    private let dependenciesArray: [PackageDependencyV54]
+    var dependencies: [PackageDependency] {
+        dependenciesArray
+    }
+
+}
+
+struct PackageDescriptionV55: PackageDescription {
+
+    enum CodingKeys: String, CodingKey {
+        case dependencyMap = "dependencies"
+    }
+
+    private let dependencyMap: [[String: [PackageDependencyV55]]]
+    var dependencies: [PackageDependency] {
+        dependencyMap.flatMap { $0.values.flatMap { $0 } }
+    }
+
+}
+
+enum PackageDescriptionFactory {
+    static func loadPackageDescription(from folder: URL) throws -> PackageDescription {
         let json = try readPackageDescription(from: folder)
         let data = json.data(using: .utf8)!
         let decoder = JSONDecoder()
         do {
-            let packageDescription = try decoder.decode(Self.self, from: data)
+            let packageDescription = try decoder.decode(PackageDescriptionV55.self, from: data)
             return packageDescription
         } catch {
-            throw PackageDescriptionError.parsingFailed(error.localizedDescription, json)
+            do {
+                let packageDescription = try decoder.decode(PackageDescriptionV54.self, from: data)
+                return packageDescription
+            } catch {
+            }
+            throw PackageDescriptionError.parsingFailed(String(describing: error), json)
         }
     }
 
@@ -94,6 +145,10 @@ struct PackageDescription: Decodable {
     }
 }
 
+protocol PackageDescription: Decodable {
+    var dependencies: [PackageDependency] { get }
+}
+
 extension PackageDescriptionError: LocalizedError {
     public var errorDescription: String? {
         switch self {

Tests/SwiftDependencyUpdaterLibraryTests/PackageDescriptionTest.swift

@@ -7,33 +7,34 @@ class PackageDescriptionTest: XCTestCase {
     func testEmptyFolder() {
         let folder = emptyFolderURL()
         assert(
-            try PackageDescription.loadPackageDescription(from: folder),
+            try PackageDescriptionFactory.loadPackageDescription(from: folder),
             throws: PackageDescriptionError.loadingFailed("error: root manifest not found")
         )
     }
 
     func testInvalidFile() {
+        var caughtError: Error?
         let folder = emptyFolderURL()
         let file = temporaryFileURL(in: folder, name: "Package.swift")
         createFile(at: file, content: "// swift-tools-version:5.4.0\n")
-        #if os(Linux)
-        assert(
-            try PackageDescription.loadPackageDescription(from: folder),
-            throws: PackageDescriptionError.loadingFailed("\(folder.path): error: malformed")
-        )
-        #else
-        assert(
-            try PackageDescription.loadPackageDescription(from: folder),
-            throws: PackageDescriptionError.loadingFailed("/private\(folder.path): error: malformed")
-        )
-        #endif
+
+        XCTAssertThrowsError(try PackageDescriptionFactory.loadPackageDescription(from: folder)) {
+            caughtError = $0
+        }
+
+        guard let error = caughtError as? PackageDescriptionError, case let .loadingFailed(description) = error else {
+            XCTFail("Unexpected error, got \(type(of: caughtError!)) \(caughtError!)) instead of PackageDescriptionError.loadingFailed")
+            return
+        }
+
+        XCTAssert(description.contains("\(folder.path): error: malformed"))
     }
 
     func testParsing() {
         let folder = emptyFolderURL()
         let file = temporaryFileURL(in: folder, name: "Package.swift")
         createFile(at: file, content: TestUtils.packageSwiftFileContent)
-        let result = try! PackageDescription.loadPackageDescription(from: folder)
+        let result = try! PackageDescriptionFactory.loadPackageDescription(from: folder)
         XCTAssertEqual(result.dependencies.count, 8)
 
         XCTAssertEqual(result.dependencies[0].name, "a")