ios-mail/Modules/InboxTesting/Sources/ExpectToEventually.swift

//
// Copyright (c) 2025 Proton Technologies AG
//
// This file is part of Proton Mail.
//
// Proton Mail is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Proton Mail is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Proton Mail. If not, see https://www.gnu.org/licenses/.

import Foundation
import Testing

@MainActor
public func expectToEventually(
    _ condition: @MainActor @escaping @autoclosure () -> Bool,
    timeout: TimeInterval = 1,
    pollInterval: TimeInterval = 0.01
) async throws {
    try await waitUntil(timeout: timeout, pollInterval: pollInterval, for: condition)
    #expect(condition())
}

@MainActor
func waitUntil(
    timeout seconds: TimeInterval,
    pollInterval: TimeInterval = 0.01,
    for condition: @MainActor @escaping () -> Bool
) async throws {
    let currentDate = Date()
    let deadline = currentDate.addingTimeInterval(seconds)

    while currentDate < deadline {
        if condition() {
            return
        }
        try await Task.sleep(for: .seconds(pollInterval))
    }

    throw TimeoutError()
}

private struct TimeoutError: Error {}