Fix refreshing of subscription preference pane when switching between…

… panes (#2230)

Task/Issue URL:
https://app.asana.com/0/1199230911884351/1206654425458681/f
Tech Design URL:
CC:

**Description**:
Fix refreshing of subscription preference pane when switching between
panes.
Also the task var was not nilled so it was only fired once per viewModel
instance.
Additionally the check for the expiry date of subscription was wrong and
it preemptively cleared cached entitlements resulting in blinking and
refresh for every settings pane switch.

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LocalPackages/SubscriptionUI/Sources/SubscriptionUI/Preferences/PreferencesSubscriptionModel.swift

@@ -173,14 +173,18 @@ public final class PreferencesSubscriptionModel: ObservableObject {
     func fetchAndUpdateSubscriptionDetails() {
         guard fetchSubscriptionDetailsTask == nil else { return }
 
-        fetchSubscriptionDetailsTask = Task {
-            guard let token = accountManager.accessToken else { return }
+        fetchSubscriptionDetailsTask = Task { [weak self] in
+            defer {
+                self?.fetchSubscriptionDetailsTask = nil
+            }
+
+            guard let token = self?.accountManager.accessToken else { return }
 
             if let cachedDate = SubscriptionService.cachedSubscriptionDetailsResponse?.expiresOrRenewsAt {
-                updateDescription(for: cachedDate)
+                self?.updateDescription(for: cachedDate)
 
-                if cachedDate.timeIntervalSinceNow > 0 {
-                    self.cachedEntitlements = []
+                if cachedDate.timeIntervalSinceNow < 0 {
+                    self?.cachedEntitlements = []
                 }
             }
 
@@ -190,13 +194,13 @@ public final class PreferencesSubscriptionModel: ObservableObject {
                     return
                 }
 
-                updateDescription(for: response.expiresOrRenewsAt)
+                self?.updateDescription(for: response.expiresOrRenewsAt)
 
-                subscriptionPlatform = response.platform
+                self?.subscriptionPlatform = response.platform
             }
 
             if case let .success(entitlements) = await AccountManager().fetchEntitlements() {
-                self.cachedEntitlements = entitlements
+                self?.cachedEntitlements = entitlements
             }
         }
     }