Patched (temporarily) the DocC documentation (#8)

This PR contains the work done to:
* Documented the public properties, initializers, and/or functions of those types conforming to the `APIClient`, `KeyNameFilter`, and `KeyNameModel` protocols, to fix the issue that the protocol documentations cannot be inherited;
* Moved the `AmiiboService` DocC documentation catalog inside the library target;
* Amended the folder structure of the library and test targets;
* Fixed further documentation issues encountered while revising the written documentation;
* Added the `lib-test` task in the `Makefile` file;
* Improved the naming for the existing tasks in the `Makefile` file.

Reviewed-on: #8
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Sources/AmiiboService/Public/Clients/AmiiboMockClient.swift

@@ -0,0 +1,179 @@
+//===----------------------------------------------------------------------===
+//
+// This source file is part of the AmiiboService open source project
+//
+// Copyright (c) 2024-2025 Röck+Cöde VoF. and the AmiiboAPI project authors
+// Licensed under the EUPL 1.2 or later.
+//
+// See LICENSE for license information
+// See CONTRIBUTORS for the list of AmiiboAPI project authors
+//
+//===----------------------------------------------------------------------===
+
+import Foundation
+
+/// A type that implements a mock client, for testing purposes.
+public struct AmiiboMockClient {
+    
+    // MARK: Properties
+    
+    /// A list of amiibo items to return, if any.
+    private let amiibos: [Amiibo]?
+    
+    /// A list of amiibo series to return, if any.
+    private let amiiboSeries: [AmiiboSeries]?
+    
+    /// A list of amiibo types to return, if any.
+    private let amiiboTypes: [AmiiboType]?
+    
+    /// An error to throw, if any.
+    private let error: AmiiboServiceError?
+    
+    /// A list of game characters to return, if any.
+    private let gameCharacters: [GameCharacter]?
+    
+    /// A list of game series to return, if any.
+    private let gameSeries: [GameSeries]?
+    
+    /// A last updated date to return, if any.
+    private let lastUpdated: Date?
+    
+    // MARK: Initializers
+    
+    /// Initializes this client.
+    /// - Parameters:
+    ///   - amiibos: A list of amiibo items to return, if any.
+    ///   - amiiboSeries: A list of amiibo series to return, if any.
+    ///   - amiiboTypes: A list of amiibo types to return, if any.
+    ///   - gameCharacters: A list of game characters to return, if any.
+    ///   - gameSeries: A list of game series to return, if any.
+    ///   - lastUpdated: A last updated date to return, if any.
+    ///   - error: An error to throw, if any. 
+    public init(
+        amiibos: [Amiibo]? = nil,
+        amiiboSeries: [AmiiboSeries]? = nil,
+        amiiboTypes: [AmiiboType]? = nil,
+        gameCharacters: [GameCharacter]? = nil,
+        gameSeries: [GameSeries]? = nil,
+        lastUpdated: Date? = nil,
+        error: AmiiboServiceError? = nil
+    ) {
+        self.amiibos = amiibos
+        self.amiiboSeries = amiiboSeries
+        self.amiiboTypes = amiiboTypes
+        self.error = error
+        self.gameCharacters = gameCharacters
+        self.gameSeries = gameSeries
+        self.lastUpdated = lastUpdated
+    }
+    
+}
+
+// MARK: - APIClient
+// TODO: Remove the documentation from the functions inside the following extension as the `--enable-inherited-docs` flag when generating DocC documentation is not working as intended (?).
+
+extension AmiiboMockClient: APIClient {
+    
+    // MARK: Functions
+
+    /// Gets a list of amiibo items based on a given filter.
+    /// - Parameter filter: A filter to remove unwanted items from the result.
+    /// - Returns: A list of filtered amiibo items.
+    /// - Throws: An ``AmiiboServiceError`` error in case some issue is encountered while generating the result.
+    public func getAmiibos(by filter: AmiiboFilter) async throws(AmiiboServiceError) -> [Amiibo] {
+        try throwErrorIfExists()
+
+        guard let amiibos else {
+            throw AmiiboServiceError.notFound
+        }
+        
+        return amiibos
+    }
+
+    /// Gets a list of amiibo series based on a given filter.
+    /// - Parameter filter: A filter to remove unwanted items from the result.
+    /// - Returns: A list of filtered amiibo series.
+    /// - Throws: An ``AmiiboServiceError`` error in case some issue is encountered while generating the result.
+    public func getAmiiboSeries(by filter: AmiiboSeriesFilter) async throws(AmiiboServiceError) -> [AmiiboSeries] {
+        try throwErrorIfExists()
+
+        guard let amiiboSeries else {
+            throw AmiiboServiceError.notFound
+        }
+        
+        return amiiboSeries
+    }
+
+    /// Gets a list of amiibo types based on a given filter.
+    /// - Parameter filter: A filter to remove unwanted items from the result.
+    /// - Returns: A list of filtered amiibo types.
+    /// - Throws: An ``AmiiboServiceError`` error in case some issue is encountered while generating the result.
+    public func getAmiiboTypes(by filter: AmiiboTypeFilter) async throws(AmiiboServiceError) -> [AmiiboType] {
+        try throwErrorIfExists()
+
+        guard let amiiboTypes else {
+            throw AmiiboServiceError.notFound
+        }
+        
+        return amiiboTypes
+    }
+
+    /// Gets a list of game characters based on a given filter.
+    /// - Parameter filter: A filter to remove unwanted items from the result.
+    /// - Returns: A list of filtered game characters.
+    /// - Throws: An ``AmiiboServiceError`` error in case some issue is encountered while generating the result.
+    public func getGameCharacters(by filter: GameCharacterFilter) async throws(AmiiboServiceError) -> [GameCharacter] {
+        try throwErrorIfExists()
+
+        guard let gameCharacters else {
+            throw AmiiboServiceError.notFound
+        }
+        
+        return gameCharacters
+    }
+
+    /// Gets a list of game series based on a given filter.
+    /// - Parameter filter: A filter to remove unwanted items from the result.
+    /// - Returns: A list of filtered game series.
+    /// - Throws: An ``AmiiboServiceError`` error in case some issue is encountered while generating the result.
+    public func getGameSeries(by filter: GameSeriesFilter) async throws(AmiiboServiceError) -> [GameSeries] {
+        try throwErrorIfExists()
+
+        guard let gameSeries else {
+            throw AmiiboServiceError.notFound
+        }
+        
+        return gameSeries
+    }
+
+    /// Gets the date when the data was last updated.
+    /// - Returns: A last updated date.
+    /// - Throws: An ``AmiiboServiceError`` error in case some issue is encountered while generating the result.
+    public func getLastUpdated() async throws(AmiiboServiceError) -> Date {
+        try throwErrorIfExists()
+
+        guard let lastUpdated else {
+            throw AmiiboServiceError.notFound
+        }
+        
+        return lastUpdated
+    }
+    
+    
+}
+
+// MARK: - Helpers
+
+private extension AmiiboMockClient {
+    
+    // MARK: Functions
+    
+    /// Throws an error if it has been provided,
+    /// - Throws: An ``AmiiboServiceError`` error in case an error has been provided.
+    func throwErrorIfExists() throws(AmiiboServiceError) {
+        if let error {
+            throw error
+        }
+    }
+    
+}