carton/Sources/CartonKit/Helpers/Expectation.swift

31 lines
1.1 KiB
Swift

// Copyright 2020 Carton contributors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
import Foundation
public struct ExpectationError: Error, CustomStringConvertible {
public let description: String
}
/** Implements throwing equality assertions, as compared to standard assertions that trap
in debug mode.
*/
struct Equality<T: Equatable, C> {
let description: (_ x: T, _ y: T, _ context: C) -> String
func callAsFunction(_ x: T, _ y: T, context: C) throws {
guard x == y else { throw ExpectationError(description: description(x, y, context)) }
}
}