From 71c4db0258c519894c13361116fca27aaea5df48 Mon Sep 17 00:00:00 2001
From: Zihe Jia <zihe.jia@mixpanel.com>
Date: Mon, 27 Jun 2022 13:08:57 -0700
Subject: [PATCH] add tests

---
 .../MixpanelDemoTests/MixpanelDemoTests.swift | 36 +++++++++++++++++++
 Sources/MixpanelInstance.swift                |  6 ++++
 2 files changed, 42 insertions(+)

diff --git a/MixpanelDemo/MixpanelDemoTests/MixpanelDemoTests.swift b/MixpanelDemo/MixpanelDemoTests/MixpanelDemoTests.swift
index e18e5bb6..3b162e43 100644
--- a/MixpanelDemo/MixpanelDemoTests/MixpanelDemoTests.swift
+++ b/MixpanelDemo/MixpanelDemoTests/MixpanelDemoTests.swift
@@ -298,6 +298,42 @@ class MixpanelDemoTests: MixpanelBaseTests {
         }
         removeDBfile(testMixpanel.apiToken)
     }
+    
+    func testCreateAlias() {
+        let testMixpanel = Mixpanel.initialize(token: randomId(), flushInterval: 60)
+        testMixpanel.people.set(properties:  ["p1": "a"])
+        waitForTrackingQueue(testMixpanel)
+        var unidentifiedQueue = unIdentifiedPeopleQueue(token: testMixpanel.apiToken)
+        // the user profile update has been queued up in unidentifiedQueue until identify is called
+        XCTAssertTrue(!unidentifiedQueue.isEmpty)
+        
+        let distinctId = testMixpanel.distinctId
+        let alias: String = "a1"
+        testMixpanel.createAlias(alias, distinctId: testMixpanel.distinctId)
+        waitForTrackingQueue(testMixpanel)
+
+        let mixpanelIdentity = MixpanelPersistence.loadIdentity(apiToken: testMixpanel.apiToken)
+        XCTAssertTrue(distinctId == mixpanelIdentity.distinctID && distinctId == mixpanelIdentity.peopleDistinctID  && distinctId == mixpanelIdentity.userId && alias == mixpanelIdentity.alias)
+        removeDBfile(testMixpanel.apiToken)
+        unidentifiedQueue = unIdentifiedPeopleQueue(token: testMixpanel.apiToken)
+        // unidentifiedQueue has been flushed
+        XCTAssertTrue(unidentifiedQueue.isEmpty)
+        
+        let testMixpanel2 = Mixpanel.initialize(token: randomId(), flushInterval: 60)
+        testMixpanel2.people.set(properties:  ["p1": "a"])
+        waitForTrackingQueue(testMixpanel2)
+        
+        let distinctId2 = testMixpanel2.distinctId
+        testMixpanel2.createAlias(alias, distinctId: testMixpanel.distinctId, andIdentify: false)
+        waitForTrackingQueue(testMixpanel2)
+        
+        let unidentifiedQueue2 = unIdentifiedPeopleQueue(token: testMixpanel2.apiToken)
+        // The user profile updates should still be held in unidentifiedQueue cause no identify is called
+        XCTAssertTrue(!unidentifiedQueue2.isEmpty)
+        let mixpanelIdentity2 = MixpanelPersistence.loadIdentity(apiToken: testMixpanel2.apiToken)
+        XCTAssertTrue(distinctId2 == mixpanelIdentity2.distinctID && nil == mixpanelIdentity2.peopleDistinctID && nil == mixpanelIdentity2.userId && alias == mixpanelIdentity2.alias)
+        removeDBfile(testMixpanel2.apiToken)
+    }
 
     func testPersistentIdentity() {
         let testMixpanel = Mixpanel.initialize(token: randomId(), flushInterval: 60)
diff --git a/Sources/MixpanelInstance.swift b/Sources/MixpanelInstance.swift
index 03c8b5e8..9d05891e 100644
--- a/Sources/MixpanelInstance.swift
+++ b/Sources/MixpanelInstance.swift
@@ -612,6 +612,12 @@ extension MixpanelInstance {
                 self.hadPersistedDistinctId = true
             }
             
+            if self.userId == nil {
+                self.readWriteLock.write {
+                    self.userId = distinctId
+                }
+            }
+            
             if distinctId != self.distinctId {
                 let oldDistinctId = self.distinctId
                 self.readWriteLock.write {