colibri/Tests/Library/Services/FileServiceTests.swift

import Foundation
import Testing

@testable import ColibriLibrary

struct FileServiceTests {
    
    // MARK: Properties
    
    private let service: FileServicing
    
    // MARK: Initialisers
    
    init() {
        self.service = FileService()
    }

    // MARK: Properties tests

    @Test func currentFolder() async {
        // GIVEN
        // WHEN
        let url = await service.currentFolder

        // THEN
        #expect(url == .someExistingFolder)
        #expect(url.isFileURL == true)
    }
        // GIVEN
        // WHEN
        // THEN
    }
    
    @Test(arguments: zip([URL.someExistingFolder, .someExistingFile, .someNonExistingFolder, .someNonExistingFile],
                         [true, true, false, false]))
    func exists(
        with url: URL,
        expects outcome: Bool
    ) async throws {
        // GIVEN
        // WHEN
        let result = try await service.exists(at: url)
        
        // THEN
        #expect(result == outcome)
    }
    
    @Test func existsThrows() async throws {
        // GIVEN
        let url = URL.someRandomURL

        // WHEN
        // THEN
        await #expect(throws: FileServiceError.urlNotFileURL) {
            try await service.exists(at: url)
        }
    }

}

// MARK: - URL+Constants

private extension URL {
    static let someExistingFolder = URL(at: "/private/tmp")
    static let someExistingFile = URL(at: "/etc/null")
    static let someNonExistingFolder = URL(at: "/some/random/folder")
    static let someNonExistingFile = URL(at: "/some/random/file.ext")
    static let someRandomURL = URL(string: "https://some.random.url")!
}