[auth-swift] AuthDispatcherTests.swift (#11339)

Author: paulb777

FirebaseAuth/Sources/Swift/Auth/AuthDispatcher.swift

@@ -14,19 +14,16 @@
 
 import Foundation
 
-// TODO: Get rid of public's and @objc's once FirebaseAuth.m is in Swift.
-
 /** @class AuthDispatcher
     @brief A utility class used to facilitate scheduling tasks to be executed in the future.
  */
-@objc(FIRAuthDispatcher) public class AuthDispatcher: NSObject {
-  @objc(sharedInstance) public static let shared = AuthDispatcher()
+class AuthDispatcher {
+  static let shared = AuthDispatcher()
 
   /** @property dispatchAfterImplementation
       @brief Allows custom implementation of dispatchAfterDelay:queue:callback:.
       @remarks Set to nil to restore default implementation.
    */
-  @objc public
   var dispatchAfterImplementation: ((TimeInterval, DispatchQueue, @escaping () -> Void) -> Void)?
 
   /** @fn dispatchAfterDelay:queue:callback:
@@ -36,7 +33,6 @@ import Foundation
       @param queue The dispatch queue on which the task will be submitted.
       @param task The task (block) to be scheduled for future execution.
    */
-  @objc public
   func dispatch(afterDelay delay: TimeInterval, queue: DispatchQueue, task: @escaping () -> Void) {
     if let dispatchAfterImplementation {
       dispatchAfterImplementation(delay, queue, task)

FirebaseAuth/Tests/Unit/AuthDispatcherTests.swift

@@ -0,0 +1,71 @@
+// Copyright 2023 Google LLC
+//
+// 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
+import XCTest
+
+@testable import FirebaseAuth
+
+class AuthDispatcherTests: XCTestCase {
+  let kTestDelay = 0.1
+  let kMaxDifferenceBetweenTimeIntervals = 0.3
+
+  /** @fn testSharedInstance
+      @brief Tests @c sharedInstance returns the same object.
+   */
+  func testSharedInstance() {
+    let instance1 = AuthDispatcher.shared
+    let instance2 = AuthDispatcher.shared
+    XCTAssert(instance1 === instance2)
+  }
+
+  /** @fn testDispatchAfterDelay
+      @brief Tests @c dispatchAfterDelay indeed dispatches the specified task after the provided
+          delay.
+   */
+  func testDispatchAfterDelay() {
+    let dispatcher = AuthDispatcher.shared
+    let testWorkQueue = DispatchQueue(label: "test.work.queue")
+    let expectation = self.expectation(description: #function)
+    let dateBeforeDispatch = Date()
+    dispatcher.dispatchAfterImplementation = nil
+    dispatcher.dispatch(afterDelay: kTestDelay, queue: testWorkQueue) { [self] in
+      let timeSinceDispatch = fabs(dateBeforeDispatch.timeIntervalSinceNow - self.kTestDelay)
+      XCTAssertLessThan(timeSinceDispatch, kMaxDifferenceBetweenTimeIntervals)
+      expectation.fulfill()
+    }
+    waitForExpectations(timeout: 5)
+  }
+
+  /** @fn testSetDispatchAfterImplementation
+      @brief Tests that @c dispatchAfterImplementation indeed configures a custom implementation for
+          @c dispatchAfterDelay.
+   */
+  func testSetDispatchAfterImplementation() {
+    let dispatcher = AuthDispatcher.shared
+    let testWorkQueue = DispatchQueue(label: "test.work.queue")
+    let expectation = self.expectation(description: #function)
+    dispatcher.dispatchAfterImplementation = { delay, queue, task in
+      XCTAssertEqual(self.kTestDelay, delay)
+      XCTAssertEqual(testWorkQueue, queue)
+      expectation.fulfill()
+    }
+
+    dispatcher.dispatch(afterDelay: kTestDelay, queue: testWorkQueue) {
+      // Fail to ensure this code is never executed.
+      XCTFail("Should not execute this code")
+    }
+    waitForExpectations(timeout: 5)
+  }
+}