#399

frontend/src/lib/useUnsavedChangesGuard.tsx

@@ -35,7 +35,7 @@ const UnsavedChangesGuardContext =
 export const UnsavedChangesGuardProvider: FC<PropsWithChildren> = ({ children }) => {
   const dialogue = useDialogue ()
   const sourcesRef = useRef (new Map<symbol, UnsavedChangesSource> ())
-  const bypassNextNavigationRef = useRef (false)
+  const bypassNextNavigationRef = useRef<symbol | null> (null)
   const [revision, setRevision] = useState (0)
   const dialogueOpenRef = useRef (false)
 
@@ -55,7 +55,13 @@ export const UnsavedChangesGuardProvider: FC<PropsWithChildren> = ({ children })
   }, [])
 
   const allowNextNavigation = useCallback (() => {
-    bypassNextNavigationRef.current = true
+    const token = Symbol ('allowed-navigation')
+    bypassNextNavigationRef.current = token
+
+    queueMicrotask (() => {
+      if (bypassNextNavigationRef.current === token)
+        bypassNextNavigationRef.current = null
+    })
   }, [])
 
   const sources = useMemo (
@@ -68,16 +74,13 @@ export const UnsavedChangesGuardProvider: FC<PropsWithChildren> = ({ children })
   )
   const hasUnsavedChanges = dirtySources.length > 0
   const shouldBlock = useCallback (() => {
-    if (!(hasUnsavedChanges))
-      return false
-
-    if (bypassNextNavigationRef.current)
+    if (bypassNextNavigationRef.current != null)
       {
         bypassNextNavigationRef.current = false
         return false
       }
 
-    return true
+    return hasUnsavedChanges
   }, [hasUnsavedChanges])
   const blocker = useBlocker (shouldBlock)