grpc-swift/Tests/GRPCHTTP2CoreTests/Test Utilities/XCTest+Utilities.swift

/*
 * Copyright 2024, gRPC Authors All rights reserved.
 *
 * 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 GRPCCore
import XCTest

func XCTAssertThrowsError<T, E: Error>(
  ofType: E.Type,
  _ expression: @autoclosure () throws -> T,
  _ errorHandler: (E) -> Void
) {
  XCTAssertThrowsError(try expression()) { error in
    guard let error = error as? E else {
      return XCTFail("Error had unexpected type '\(type(of: error))'")
    }
    errorHandler(error)
  }
}

func XCTAssertDescription(
  _ subject: some CustomStringConvertible,
  _ expected: String,
  file: StaticString = #filePath,
  line: UInt = #line
) {
  XCTAssertEqual(String(describing: subject), expected, file: file, line: line)
}

@available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *)
func XCTUnwrapAsync<T>(_ expression: () async throws -> T?) async throws -> T {
  let value = try await expression()
  return try XCTUnwrap(value)
}

@available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *)
func XCTAssertThrowsErrorAsync<T, E: Error>(
  ofType: E.Type = E.self,
  _ expression: () async throws -> T,
  errorHandler: (E) -> Void
) async {
  do {
    _ = try await expression()
    XCTFail("Expression didn't throw")
  } catch let error as E {
    errorHandler(error)
  } catch {
    XCTFail("Error had unexpected type '\(type(of: error))'")
  }
}

func XCTAssert<T>(_ value: Any, as type: T.Type, _ verify: (T) throws -> Void) rethrows {
  if let value = value as? T {
    try verify(value)
  } else {
    XCTFail("\(value) couldn't be cast to \(T.self)")
  }
}

@available(macOS 13.0, iOS 16.0, watchOS 9.0, tvOS 16.0, *)
func XCTPoll(
  every interval: Duration,
  timeLimit: Duration = .seconds(5),
  until predicate: () async throws -> Bool
) async throws {
  let becameTrue = try await Task.poll(every: interval, timeLimit: timeLimit, until: predicate)
  XCTAssertTrue(becameTrue, "Predicate didn't return true within \(timeLimit)")
}