Migration Guide (v4)

This guide explains the major changes in version 4 provides step-by-step instructions to update your code.

1. Adjust for the New `BasePaginator` and Lifecycle Events

Centralized Logic:
v4 introduces a BasePaginator<T> class that centralizes shared logic such as debouncing and disposal checks.
Action:
- If you previously subclassed Paginator directly, consider extending either BasePaginator<T> or the new Paginator<T>.
- Override the onPageChanged method if you need custom behavior on page transitions. This replaces any older custom hooking mechanisms around goToPage.

2. Handle Casting and Transformations

Transformation Methods:
Earlier versions might have returned raw lists or used a different caching mechanism for methods like where() or sort().
Action:
- In v4, these methods now return fully instantiated Paginator<T> objects, stored internally in a time-based _transformCache.
- Update your code to work with the returned Paginator<T> instances instead of accessing raw transformation results.

3. Use of `CancelableOperation` in `AsyncPaginator` (Optional)

Avoid Overlapping Requests:
The new implementation uses CancelableOperation to deduplicate and cancel overlapping fetch requests.
Action:
- Set autoCancelFetches to true in your PaginationConfig if you want to prevent concurrent fetches.
- If you prefer the old behavior (allowing multiple simultaneous requests), set autoCancelFetches to false.

4. Infinite Paginator Changes

Unified Infinite Scrolling:
The InfinitePaginator now supports both page-based and cursor-based approaches via factory constructors.
Action:
- Replace any legacy infinite scroll classes or custom implementations with either InfinitePaginator.pageBased() or InfinitePaginator.cursorBased().
- Adapt any direct usage of pagination keys to match the new factory constructor signatures.

5. Updated Number Extensions for Delay Methods

Specific Duration Methods:
The generic delay() method has been replaced by more specific duration-based delay methods.

Action: Replace old delay methods as follows:
- Replace await 2.delay(); and await 2.secDelay; with await 2.secondsDelay();
- Replace await 5.minDelay; with await 5.minutesDelay();
- Replace await 1.daysDelay; with await 1.daysDelay();
- And so on for other time units.
Additionally, if you previously used a delay with a callback:
```
// Old:
await 2.delay(() => someFunction());

// New:
final result = await 2.secondsDelay(() => someFunction());
```

6. Analytics (Optional)

Tracking Metrics:
If you need to track metrics (such as page loads, errors, and cache hits), add the PaginationAnalytics mixin to your custom paginator class.

Action: Incorporate the mixin where needed to log metrics according to your application requirements.

7. Testing and Disposal Behavior

No-Op After Disposal:
In v4, methods such as goToPage are designed to be no-ops (instead of throwing exceptions) after the paginator is disposed. This ensures that lifecycle streams remain silent post-disposal.

Action:
- Update your tests to reflect this behavior.
- If your code previously expected an exception after disposal, refactor it to handle no-ops instead.
Review Your Tests:
Confirm that your existing tests pass. Update any tests that reference legacy method names, class hierarchies, or disposal behavior.

Migration Guide (v3)

Breaking Changes

String Extensions:
- Removed deprecated toDateTime method
- Use toDateFormatted or toDate instead
DateTime Extensions:
- Removed deprecated format method
- Use formatted instead
- Added stricter type checking for date operations

Migration Guide (v2)

1. Date and Time Parsing

try/toDateWithFormat renamed to try/toDateFormatted:
- Action: Update all instances of try/toDateWithFormat in your code to try/toDateFormatted.

dateFormat on String is now a method with an optional locale parameter: This change gives you more control over the formatting process, allowing you to specify the locale explicitly for accurate results.

Old Usage:

String formattedDate = '2024-06-10'.dateFormat; // Used default or current locale

New Usage:

String formattedDate = '2024-06-10'.dateFormat(); // Uses default locale
String formattedDateUS = '2024-06-10'.dateFormat('en_US'); // Explicitly uses US locale

2. `firstDayOfWeek` and `lastDayOfWeek`

These methods now have an optional startOfWeek parameter to customize the first day of the week. The default value is DateTime.monday.

Old Usage:

DateTime now = DateTime.now();
DateTime firstDayOfWeek = now.firstDayOfWeek;
DateTime lastDayOfWeek = now.lastDayOfWeek;

New Usage:

DateTime now = DateTime.now();
DateTime firstDayOfWeek = now.firstDayOfWeek(); // Defaults to Monday
DateTime lastDayOfWeek = now.lastDayOfWeek(); // Defaults to Monday

// Customize start of week (e.g., Sunday)
DateTime firstDayOfWeekSunday = now.firstDayOfWeek(startOfWeek: DateTime.sunday);

3. Map Methods

flatJson renamed to flatMap: If you were using the flatJson method on Map<String, dynamic>, update your code to use flatMap instead. The functionality has been enhanced to handle arrays, circular references, and provide an option to exclude arrays.
makeEncodable and safelyEncodedJson renamed: The makeEncodable and safelyEncodedJson methods on Map<K, V> have been renamed to encodableCopy and encodedJsonString, respectively. Additionally, an issue where sets were not correctly converted to JSON-encodable lists has been fixed.

4. Other Breaking Changes

Review the changelog for any other minor breaking changes and update your code accordingly.

Troubleshooting

If you encounter any issues during the migration process please fill an issue here.