From 8ab3c11c83f56d648336c42b86937fd1da744522 Mon Sep 17 00:00:00 2001
From: Shin Yamamoto <shin@scenee.com>
Date: Thu, 1 Sep 2022 19:53:55 +0900
Subject: [PATCH] Replace PR #551 change using fatalError()

---
 Sources/Transitioning.swift | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Sources/Transitioning.swift b/Sources/Transitioning.swift
index 8b52141c..88ab2348 100644
--- a/Sources/Transitioning.swift
+++ b/Sources/Transitioning.swift
@@ -99,15 +99,15 @@ class ModalPresentTransition: NSObject, UIViewControllerAnimatedTransitioning {
             return animator
         }
 
-        // Ensure the current(initial) state is hidden. Because `fpc.transitionAnimator` can be nil if not.
-        fpc.move(to: .hidden, animated: false)
-
         fpc.suspendTransitionAnimator(true)
         fpc.show(animated: true) { [weak fpc] in
             fpc?.suspendTransitionAnimator(false)
             transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
         }
-        return fpc.transitionAnimator!
+        guard let transitionAnimator = fpc.transitionAnimator else {
+            fatalError("The panel state must be `hidden` but it is `\(fpc.state)`")
+        }
+        return transitionAnimator
     }
 
     func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {