ResultPublishers Tests

ResultPublisherTests.swift

import XCTest

// Depends on SP: https://github.com/albertbori/TestableCombinePublishers
import TestableCombinePublishers

final class ResultPublisherTests: XCTestCase {
    
    func testSuccess() {
        ResultPublisher<String, Error> { [weak self] in
            self?.basicSuccess(completion: $0)
        }
        .expect("success string")
        .waitForExpectations(timeout: 1)
    }
    
    func testFailure() {
        ResultPublisher<String, Error> { [weak self] in
            self?.basicFailure(completion: $0)
        }
        .expectFailure()
        .waitForExpectations(timeout: 1)
    }
    
    func testMultiOutput() {
        ResultPublisher<String, Error> { [weak self] in
            self?.multiSuccess(completion: $0)
        }
        .expectExactly(2, { XCTAssertEqual("success string", $0) })
        .waitForExpectations(timeout: 1)
    }
    
    // MARK: - HELPERS
    
    private func basicFailure(completion: @escaping (Result<String, Error>) -> Void) {
        completion(.failure(NSError(domain: "test", code: 1)))
    }
    
    private func basicSuccess(completion: @escaping (Result<String, Error>) -> Void) {
        completion(.success("success string"))
    }
    
    private func multiSuccess(completion: @escaping (Result<String, Error>) -> Void) {
        completion(.success("success string"))
        completion(.success("success string"))
    }
}