//
//  Copyright (c) 2018 Touch Instinct
//
//  Permission is hereby granted, free of charge, to any person obtaining a copy
//  of this software and associated documentation files (the Software), to deal
//  in the Software without restriction, including without limitation the rights
//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
//  copies of the Software, and to permit persons to whom the Software is
//  furnished to do so, subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included in
//  all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
//  THE SOFTWARE.
//

public extension Optional where Wrapped: Sequence, Wrapped.Element: Equatable {
    /// Compares two optional collections with Equtable elements.
    ///
    /// - Parameters:
    ///   - lhs: First collection.
    ///   - rhs: Second collection.
    /// - Returns: True if both parameters are nil or if first collection is equal to second.
    static func == (lhs: [Wrapped.Element]?, rhs: [Wrapped.Element]?) -> Bool {
        switch (lhs, rhs) {
        case let (lhs?, rhs?):
            return lhs == rhs

        case (nil, nil):
            return true

        default:
            return false
        }
    }
}