Files
discogs-service/Sources/DiscogsService/Internal/Validation Rules/NotNilValidationRule.swift
T
javier a1a649838c Implemented an input validation mechanism (#4)
This PR contains the work done to implement the `ValidateInputUseCase` use case and the `InputValidationRule` protocol, that is essential to define custom validation rules for inputs. In addition, the `NotEmptyValidationRule` and `NotNilValidationRule` rules have also been implemented.

Reviewed-on: #4
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>
2025-10-12 13:25:25 +00:00

61 lines
1.7 KiB
Swift

// ===----------------------------------------------------------------------===
//
// This source file is part of the DiscogsService open source project
//
// Copyright (c) 2025 Röck+Cöde VoF. and the DiscogsService project authors
// Licensed under Apache license v2.0
//
// See LICENSE for license information
// See CONTRIBUTORS for the list of DiscogsService project authors
//
// SPDX-License-Identifier: Apache-2.0
//
// ===----------------------------------------------------------------------===
/// A validation rule type that checks whether an input is nil or not.
struct NotNilValidationRule: InputValidationRule {
// MARK: Functions
#if swift(>=6.0)
func validate(_ input: String?) throws(InputValidationError) -> Bool {
try validate(input: input)
}
#else
func validate(_ input: String?) throws -> Bool {
try validate(input: input)
}
#endif
}
// MARK: - Helpers
private extension NotNilValidationRule {
// MARK: Functions
/// Validates a given input.
///
/// > note: This helper function would not be necessary when support for *Swift 5.10* is discontinued.
///
/// - Parameter input: An input to be validated.
/// - Returns: A flag that indicates whether a given input has been validated or not.
/// - Throws: An error of type ``InputValidatorError`` in case the validation failed.
func validate(input: String?) throws -> Bool {
guard let input else {
throw InputValidationError.inputIsNil
}
return true
}
}
// MARK: - Constants
extension InputValidationRule where Self == NotNilValidationRule {
/// A validation rule that checks whether an input is nil or not.
static var notNil: Self { .init() }
}