From 9c436e04181349c7adce95756b9216903723d206 Mon Sep 17 00:00:00 2001
From: Kyle Bashour <kbashour@squareup.com>
Date: Fri, 7 Jan 2022 15:52:40 -0800
Subject: [PATCH 1/2] Always remove child view controller

---
 .../DescribedViewController.swift              | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/WorkflowUI/Sources/ViewControllerDescription/DescribedViewController.swift b/WorkflowUI/Sources/ViewControllerDescription/DescribedViewController.swift
index 3e6c6c000..25d8b8b45 100644
--- a/WorkflowUI/Sources/ViewControllerDescription/DescribedViewController.swift
+++ b/WorkflowUI/Sources/ViewControllerDescription/DescribedViewController.swift
@@ -42,19 +42,21 @@
             if description.canUpdate(viewController: currentViewController) {
                 description.update(viewController: currentViewController)
             } else {
-                if isViewLoaded {
-                    currentViewController.willMove(toParent: nil)
-                    currentViewController.view.removeFromSuperview()
-                    currentViewController.removeFromParent()
-                }
+                currentViewController.willMove(toParent: nil)
+                currentViewController.viewIfLoaded?.removeFromSuperview()
+                currentViewController.removeFromParent()
+
                 currentViewController = description.buildViewController()
+
+                addChild(currentViewController)
+
                 if isViewLoaded {
-                    addChild(currentViewController)
-                    view.addSubview(currentViewController.view)
                     currentViewController.view.frame = view.bounds
-                    currentViewController.didMove(toParent: self)
+                    view.addSubview(currentViewController.view)
                     updatePreferredContentSizeIfNeeded()
                 }
+
+                currentViewController.didMove(toParent: self)
             }
         }
 

From 629933221705d4101b86d58af40f61486cbe275d Mon Sep 17 00:00:00 2001
From: Kyle Bashour <kbashour@squareup.com>
Date: Fri, 7 Jan 2022 16:11:26 -0800
Subject: [PATCH 2/2] Add and fix tests

---
 WorkflowUI/Tests/DescribedViewControllerTests.swift | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/WorkflowUI/Tests/DescribedViewControllerTests.swift b/WorkflowUI/Tests/DescribedViewControllerTests.swift
index 00052a938..ed1ae499d 100644
--- a/WorkflowUI/Tests/DescribedViewControllerTests.swift
+++ b/WorkflowUI/Tests/DescribedViewControllerTests.swift
@@ -108,10 +108,11 @@
 
             // Then
             XCTAssertNotEqual(initialChildViewController, describedViewController.currentViewController)
+            XCTAssertNil(initialChildViewController.parent)
             XCTAssertEqual((describedViewController.currentViewController as? MessageViewController)?.message, "Test")
             XCTAssertFalse(describedViewController.isViewLoaded)
             XCTAssertFalse(describedViewController.currentViewController.isViewLoaded)
-            XCTAssertNil(describedViewController.currentViewController.parent)
+            XCTAssertEqual(describedViewController.currentViewController.parent, describedViewController)
         }
 
         func test_update_toIncompatibleDescription_afterViewLoads() {