Root folder creation (#2)

This PR contains the work done to create the root folder of a new project when executing the _colibri_ executable. In addition, some other work has been done:

* added the `ArgumentParser` package dependency to the package;
* implemented the `FileService` service in the _library_ target;
* implemented the `CreateRootFolderTask` task in the _library_ target;
* removed some unnecessary comments and boilerplate code;

Reviewed-on: #2
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Package.swift

@@ -4,6 +4,9 @@ import PackageDescription
 
 let package = Package(
     name: "Colibri",
+    platforms: [
+        .macOS(.v10_15)
+    ],
     products: [
         .executable(
             name: "colibri",

Sources/Executable/Colibri.swift

@@ -4,10 +4,11 @@ import ColibriLibrary
 @main
 struct Colibri: AsyncParsableCommand {
     
-    // MARK: Functions
-    
-    func run() async throws {
-        // ...
-    }
+    // MARK: Properties
+
+    static let configuration = CommandConfiguration(
+        abstract: "The utility to manage your Hummingbird apps",
+        subcommands: [Create.self]
+    )
     
 }

Sources/Executable/Commands/Create.swift

@@ -0,0 +1,56 @@
+import ArgumentParser
+import ColibriLibrary
+import Foundation
+
+extension Colibri {
+    struct Create: AsyncParsableCommand {
+        
+        // MARK: Properties
+        
+        static let configuration = CommandConfiguration(
+            commandName: "create-project",
+            abstract: "Create a new, tailored Hummingbird app",
+            helpNames: .shortAndLong,
+            aliases: ["create"]
+        )
+        
+        @OptionGroup var options: Options
+
+        // MARK: Functions
+
+        mutating func run() async throws {
+            let fileService = FileService()
+            let createRootFolder = CreateRootFolderTask(fileService: fileService)
+
+            let rootFolder = try await createRootFolder(
+                name: options.name,
+                at: options.locationURL
+            )
+
+            print(rootFolder)
+        }
+
+    }
+}
+
+// MARK: - Options
+
+extension Colibri.Create {
+    struct Options: ParsableArguments {
+     
+        // MARK: Properties
+        
+        @Option(name: .shortAndLong)
+        var name: String
+        
+        @Option(name: .shortAndLong)
+        var location: String?
+        
+        // MARK: Computed
+        
+        var locationURL: URL? {
+            location.flatMap { URL(fileURLWithPath: $0) }
+        }
+
+    }
+}

Sources/Library/Extensions/URL+Inits.swift

@@ -0,0 +1,15 @@
+import Foundation
+
+extension URL {
+    
+    // MARK: Initialisers
+    
+    init(at filePath: String) {
+        if #available(macOS 13.0, *) {
+            self = URL(filePath: filePath)
+        } else {
+            self = URL(fileURLWithPath: filePath)
+        }
+    }
+    
+}

Sources/Library/Protocols/FileServicing.swift

@@ -0,0 +1,25 @@
+import Foundation
+
+public protocol FileServicing {
+    
+    // MARK: Computed
+    
+    var currentFolder: URL { get async }
+    
+    // MARK: Functions
+    
+    func createFolder(at url: URL) async throws (FileServiceError)
+    func delete(at url: URL) async throws (FileServiceError)
+    func exists(at url: URL) async throws (FileServiceError) -> Bool
+    
+}
+
+// MARK: - Errors
+
+public enum FileServiceError: Error, Equatable {
+    case folderNotCreated
+    case urlAlreadyExists
+    case urlNotDeleted
+    case urlNotExists
+    case urlNotFileURL
+}

Sources/Library/Services/FileService.swift

@@ -0,0 +1,78 @@
+import Foundation
+
+public struct FileService: FileServicing {
+
+    // MARK: Properties
+    
+    private let fileManager: FileManager
+    
+    // MARK: Initialisers
+    
+    public init(fileManager: FileManager = .default) {
+        self.fileManager = fileManager
+    }
+    
+    // MARK: Computed
+    
+    public var currentFolder: URL {
+        get async {
+            .init(at: fileManager.currentDirectoryPath)
+        }
+    }
+    
+    // MARK: Functions
+
+    public func createFolder(at url: URL) async throws (FileServiceError) {
+        guard try await !exists(at: url) else {
+            throw FileServiceError.urlAlreadyExists
+        }
+        
+        do {
+            try fileManager.createDirectory(
+                at: url,
+                withIntermediateDirectories: true
+            )
+        } catch {
+            throw FileServiceError.folderNotCreated
+        }
+    }
+    
+    public func delete(at url: URL) async throws (FileServiceError) {
+        guard try await exists(at: url) else {
+            throw FileServiceError.urlNotExists
+        }
+        
+        do {
+            try fileManager.removeItem(at: url)
+        } catch {
+            throw FileServiceError.urlNotDeleted
+        }
+    }
+    
+    public func exists(at url: URL) async throws (FileServiceError) -> Bool {
+        guard url.isFileURL else {
+            throw FileServiceError.urlNotFileURL
+        }
+        
+        let filePath = getPath(for: url)
+        
+        return fileManager.fileExists(atPath: filePath)
+    }
+    
+}
+
+// MARK: - Helpers
+
+private extension FileService {
+    
+    // MARK: Functions
+    
+    func getPath(for url: URL) -> String {
+        if #available(macOS 13.0, *) {
+            return url.path()
+        } else {
+            return url.path
+        }
+    }
+    
+}

Sources/Library/Tasks/CreateRootFolderTask.swift

@@ -0,0 +1,48 @@
+import Foundation
+
+public struct CreateRootFolderTask {
+    
+    // MARK: Properties
+    
+    private let fileService: FileServicing
+    
+    // MARK: Initialisers
+    
+    public init(fileService: FileServicing) {
+        self.fileService = fileService
+    }
+    
+    // MARK: Functions
+    
+    public func callAsFunction(
+        name: String,
+        at location: URL? = nil
+    ) async throws -> URL {
+        guard !name.isEmpty else {
+            throw CreateRootFolderError.nameIsEmpty
+        }
+
+        let rootFolder = if let location {
+            location
+        } else {
+            await fileService.currentFolder
+        }
+        
+        let newFolder = if #available(macOS 13.0, *) {
+            rootFolder.appending(path: name)
+        } else {
+            rootFolder.appendingPathComponent(name)
+        }
+
+        try await fileService.createFolder(at: newFolder)
+        
+        return newFolder
+    }
+    
+}
+
+// MARK: - Errors
+
+public enum CreateRootFolderError: Error {
+    case nameIsEmpty
+}

Tests/Library/Cases/Services/FileServiceTests.swift

@@ -0,0 +1,154 @@
+import ColibriLibrary
+import Foundation
+import Testing
+
+struct FileServiceTests {
+    
+    // MARK: Properties
+    
+    private let spy = FileServiceSpy()
+
+    // MARK: Properties tests
+
+    @Test func currentFolder() async {
+        // GIVEN
+        let url: URL = .someCurrentFolder
+        
+        let service = FileServiceMock(currentFolder: url)
+
+        // WHEN
+        let folder = await service.currentFolder
+
+        // THEN
+        #expect(folder == url)
+        #expect(folder.isFileURL == true)
+    }
+    
+    // MARK: Functions
+    
+    @Test(arguments: [URL.someNewFolder, .someNewFile])
+    func createFolder(with url: URL) async throws {
+        // GIVEN
+        let service = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .createFolder(url),
+            spy: spy
+        )
+
+        // WHEN
+        try await service.createFolder(at: url)
+        
+        // THEN
+        #expect(spy.isCreateFolderCalled == true)
+        #expect(spy.urlCalled == url)
+    }
+    
+    @Test(arguments: zip([URL.someExistingFolder, .someExistingFile, .someRandomURL],
+                         [FileServiceError.urlAlreadyExists, .urlAlreadyExists, .urlNotFileURL]))
+    func createFolder(
+        with url: URL,
+        throws error: FileServiceError
+    ) async throws {
+        // GIVEN
+        let service = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .error(error),
+            spy: spy
+        )
+
+        // WHEN
+        // THEN
+        await #expect(throws: error) {
+            try await service.createFolder(at: url)
+        }
+
+        #expect(spy.isCreateFolderCalled == false)
+        #expect(spy.urlCalled == nil)
+    }
+    
+    @Test(arguments: [URL.someNewFolder, .someNewFile])
+    func delete(with url: URL) async throws {
+        // GIVEN
+        let service = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .delete(url),
+            spy: spy
+        )
+
+        // WHEN
+        try await service.delete(at: url)
+
+        // THEN
+        #expect(spy.isDeleteCalled == true)
+        #expect(spy.urlCalled == url)
+    }
+    
+    @Test(arguments: zip([URL.someNewFolder, .someNewFile, .someRandomURL],
+                         [FileServiceError.urlNotExists, .urlNotExists, .urlNotFileURL]))
+    func delete(
+        with url: URL,
+        throws error: FileServiceError
+    ) async throws {
+        // GIVEN
+        let service = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .error(error),
+            spy: spy
+        )
+        
+        // WHEN
+        // THEN
+        await #expect(throws: error) {
+            try await service.delete(at: url)
+        }
+
+        #expect(spy.isDeleteCalled == false)
+        #expect(spy.urlCalled == nil)
+    }
+    
+    @Test(arguments: zip([URL.someExistingFolder, .someExistingFile, .someNewFolder, .someNewFile],
+                         [true, true, false, false]))
+    func exists(
+        with url: URL,
+        expects outcome: Bool
+    ) async throws {
+        // GIVEN
+        let service = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .exists(url, outcome),
+            spy: spy
+        )
+
+        // WHEN
+        let result = try await service.exists(at: url)
+        
+        // THEN
+        #expect(result == outcome)
+
+        #expect(spy.isExistsAtCalled == true)
+        #expect(spy.urlCalled == url)
+    }
+    
+    @Test(arguments: zip([URL.someRandomURL], [FileServiceError.urlNotFileURL]))
+    func exists(
+        with url: URL,
+        throws error: FileServiceError
+    ) async throws {
+        // GIVEN
+        let service = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .error(error),
+            spy: spy
+        )
+
+        // WHEN
+        // THEN
+        await #expect(throws: error) {
+            try await service.exists(at: url)
+        }
+        
+        #expect(spy.isExistsAtCalled == false)
+        #expect(spy.urlCalled == nil)
+    }
+
+}

Tests/Library/Cases/Tasks/CreateRootFolderTaskTests.swift

@@ -0,0 +1,91 @@
+import ColibriLibrary
+import Foundation
+import Testing
+
+struct CreateRootFolderTaskTests {
+
+    // MARK: Functions tests
+    
+    @Test(arguments: [String.someProjectName], [URL.someCurrentProjectFolder, .someNewProjectFolder, .someDotProjectFolder, .someTildeProjectFolder])
+    func task(
+        name: String,
+        expects folder: URL
+    ) async throws {
+        // GIVEN
+        let location: URL? = switch folder {
+            case .someNewProjectFolder: .someNewFolder
+            case .someDotProjectFolder: .someDotFolder
+            case .someTildeProjectFolder: .someTildeFolder
+            default: nil
+        }
+        
+        let fileService = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .createFolder(folder)
+        )
+
+        let task = CreateRootFolderTask(fileService: fileService)
+
+        // WHEN
+        let result = try await task(name: name,
+                                    at: location)
+        
+        // THEN
+        #expect(result == folder)
+        #expect(result.isFileURL == true)
+    }
+    
+    @Test(arguments: [String.someProjectName], [FileServiceError.urlAlreadyExists])
+    func task(
+        name: String,
+        throws error: FileServiceError
+    ) async throws {
+        // GIVEN
+        let fileService = FileServiceMock(
+            currentFolder: .someCurrentFolder,
+            action: .error(error)
+        )
+        
+        let task = CreateRootFolderTask(fileService: fileService)
+        
+        // WHEN
+        // THEN
+        await #expect(throws: error) {
+            try await task(name: name)
+        }
+    }
+    
+    @Test(arguments: [String.someEmptyName], [CreateRootFolderError.nameIsEmpty])
+    func task(
+        name: String,
+        throws error: CreateRootFolderError
+    ) async throws {
+        // GIVEN
+        let fileService = FileServiceMock(currentFolder: .someCurrentFolder)
+        
+        let task = CreateRootFolderTask(fileService: fileService)
+        
+        // WHEN
+        // THEN
+        await #expect(throws: error) {
+            try await task(name: name)
+        }
+    }
+
+}
+
+// MARK: - String+Constants
+
+private extension String {
+    static let someEmptyName = ""
+    static let someProjectName = "SomeProjectName"
+}
+
+// MARK: - URL+Constants
+
+private extension URL {
+    static let someCurrentProjectFolder = URL.someCurrentFolder.appending(component: String.someProjectName)
+    static let someDotProjectFolder = URL.someDotFolder.appending(component: String.someProjectName)
+    static let someNewProjectFolder = URL.someNewFolder.appending(component: String.someProjectName)
+    static let someTildeProjectFolder = URL.someTildeFolder.appending(component: String.someProjectName)
+}

Tests/Library/Helpers/Extensions/URL+Samples.swift

@@ -0,0 +1,18 @@
+import Foundation
+
+@testable import ColibriLibrary
+
+extension URL {
+    
+    // MARK: Constants
+    
+    static let someCurrentFolder = URL(at: "/some/current/folder")
+    static let someDotFolder = URL(at: ".")
+    static let someExistingFolder = URL(at: "/some/existing/folder")
+    static let someExistingFile = URL(at: "/some/existing/file")
+    static let someNewFolder = URL(at: "/some/new/folder")
+    static let someNewFile = URL(at: "/some/new/file")
+    static let someRandomURL = URL(string: "http://some.random.url")!
+    static let someTildeFolder = URL(at: "~")
+    
+}

Tests/Library/Helpers/Mocks/FileServiceMock.swift

@@ -0,0 +1,84 @@
+import ColibriLibrary
+import Foundation
+
+struct FileServiceMock {
+    
+    // MARK: Properties
+    
+    private let action: Action?
+    private let folder: URL
+    
+    private weak var spy: FileServiceSpy?
+    
+    // MARK: Initialisers
+    
+    init(
+        currentFolder: URL,
+        action: Action? = nil,
+        spy: FileServiceSpy? = nil
+    ) {
+        self.action = action
+        self.folder = currentFolder
+        self.spy = spy
+    }
+    
+}
+
+// MARK: - FileServicing
+
+extension FileServiceMock: FileServicing {
+    
+    // MARK: Computed
+    
+    var currentFolder: URL {
+        get async { folder }
+    }
+    
+    // MARK: Functions
+    
+    func createFolder(at url: URL) async throws(FileServiceError) {
+        switch action {
+        case .error(let error):
+            throw error
+        case let .createFolder(url):
+            try await spy?.createFolder(at: url)
+        default:
+            break
+        }
+    }
+    
+    func delete(at url: URL) async throws(FileServiceError) {
+        switch action {
+        case .error(let error):
+            throw error
+        case let .delete(url):
+            try await spy?.delete(at: url)
+        default:
+            break
+        }
+    }
+    
+    func exists(at url: URL) async throws(FileServiceError) -> Bool {
+        switch action {
+        case .error(let error):
+            throw error
+        case let .exists(url, exists):
+            try await spy?.exists(at: url)
+            return exists
+        default:
+            return false
+        }
+    }
+    
+}
+
+// MARK: - Enumerations
+
+extension FileServiceMock {
+    enum Action {
+        case createFolder(URL)
+        case delete(URL)
+        case error(FileServiceError)
+        case exists(URL, Bool)
+    }
+}

Tests/Library/Helpers/Spies/FileServiceSpy.swift

@@ -0,0 +1,41 @@
+import Foundation
+
+@testable import ColibriLibrary
+
+final class FileServiceSpy {
+    
+    // MARK: Properties
+    
+    private(set) var isCreateFolderCalled: Bool = false
+    private(set) var isDeleteCalled: Bool = false
+    private(set) var isExistsAtCalled: Bool = false
+    private(set) var urlCalled: URL?
+    
+}
+
+// MARK: - FileServicing
+
+extension FileServiceSpy: FileServicing {
+    var currentFolder: URL {
+        get async { .someCurrentFolder }
+    }
+    
+    func createFolder(at url: URL) async throws(FileServiceError) {
+        isCreateFolderCalled = true
+        urlCalled = url
+    }
+    
+    func delete(at url: URL) async throws(FileServiceError) {
+        isDeleteCalled = true
+        urlCalled = url
+    }
+    
+    @discardableResult
+    func exists(at url: URL) async throws(FileServiceError) -> Bool {
+        isExistsAtCalled = true
+        urlCalled = url
+        
+        return .random()
+    }
+    
+}