[tests] Add test for switching users with adding tags

* Starts with anon user, log into 2 users via Identify User and Create User
* Add tags to each user

Author: nan-li

iOS_SDK/OneSignalSDK/OneSignalUserTests/OneSignalUserTests.swift

@@ -43,7 +43,7 @@ final class OneSignalUserTests: XCTestCase {
     }
 
     override func tearDownWithError() throws {
-        // TODO: Need to clear all data between tests for user manager, models, etc.
+        // TODO: Need to clear all data between tests for client, user manager, models, etc.
         OneSignalCoreMocks.clearUserDefaults()
         OneSignalUserMocks.reset()
     }
@@ -137,4 +137,83 @@ final class OneSignalUserTests: XCTestCase {
             identityModel.clearData()
         }
     }
+
+    func testSwitchUser_sendsCorrectTags() throws {
+        /* Setup */
+
+        let client = MockOneSignalClient()
+
+        // 1. Set up mock responses for the anonymous user
+        let anonCreateResponse = MockUserRequests.testIdentityPayload(onesignalId: anonUserOSID, externalId: nil)
+
+        client.setMockResponseForRequest(
+            request: "<OSRequestCreateUser with externalId: nil>",
+            response: anonCreateResponse)
+
+        // 2. Set up mock responses for User A
+        let tagsUserA = ["tag_a": "value_a"]
+        let createUserA = MockUserRequests.testIdentityPayload(onesignalId: userA_OSID, externalId: userA_EUID)
+        let tagsResponseUserA = MockUserRequests.testPropertiesPayload(properties: ["tags": tagsUserA])
+
+        client.setMockResponseForRequest(
+            request: "<OSRequestIdentifyUser with aliasLabel: external_id aliasId: \(userA_EUID)>",
+            response: createUserA
+        )
+        client.setMockResponseForRequest(
+            request: "<OSRequestFetchUser with aliasLabel: external_id aliasId: \(userA_EUID)>",
+            response: createUserA
+        )
+        client.setMockResponseForRequest(
+            request: "<OSRequestUpdateProperties with properties: [\"tags\": \(tagsUserA)] deltas: nil refreshDeviceMetadata: false>",
+            response: tagsResponseUserA
+        )
+
+        // 3. Set up mock responses for User B
+        let tagsUserB = ["tag_b": "value_b"]
+        let createUserB = MockUserRequests.testIdentityPayload(onesignalId: userB_OSID, externalId: userB_EUID)
+        let tagsResponseUserB = MockUserRequests.testPropertiesPayload(properties: ["tags": tagsUserB])
+
+        client.setMockResponseForRequest(
+            request: "<OSRequestCreateUser with externalId: \(userB_EUID)>",
+            response: createUserB
+        )
+        client.setMockResponseForRequest(
+            request: "<OSRequestFetchUser with aliasLabel: external_id aliasId: \(userB_EUID)>",
+            response: createUserB
+        )
+        client.setMockResponseForRequest(
+            request: "<OSRequestUpdateProperties with properties: [\"tags\": \(tagsUserB)] deltas: nil refreshDeviceMetadata: false>",
+            response: tagsResponseUserB)
+
+        OneSignalCoreImpl.setSharedClient(client)
+
+        /* When */
+
+        // 1. Login to user A and add tag
+        OneSignalUserManagerImpl.sharedInstance.login(externalId: userA_EUID, token: nil)
+        OneSignalUserManagerImpl.sharedInstance.addTag(key: "tag_a", value: "value_a")
+
+        // 2. Login to user B and add tag
+        OneSignalUserManagerImpl.sharedInstance.login(externalId: userB_EUID, token: nil)
+        OneSignalUserManagerImpl.sharedInstance.addTag(key: "tag_b", value: "value_b")
+
+        // 3. Run background threads
+        OneSignalCoreMocks.waitForBackgroundThreads(seconds: 0.5)
+
+        /* Then */
+        
+        // Assert that every request SDK makes has a response set, and is handled
+        XCTAssertTrue(client.allRequestsHandled)
+
+        // Assert there is only one request containing these tags and they are sent to userA
+        XCTAssertTrue(client.onlyOneRequest(
+            contains: "apps/test-app-id/users/by/onesignal_id/\(userA_OSID)",
+            contains: ["properties": ["tags": tagsUserA]])
+        )
+        // Assert there is only one request containing these tags and they are sent to userB
+        XCTAssertTrue(client.onlyOneRequest(
+            contains: "apps/test-app-id/users/by/onesignal_id/\(userB_OSID)",
+            contains: ["properties": ["tags": tagsUserB]])
+        )
+    }
 }