Implement Unwrapped Cells for Improved Type Safety #1382
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Thank you for noticing this. Please resubmit with the following change: rather than fatalError(), which will crash in production, return nil when the cell is nil or of an unexpected type: |
whattherestimefor
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whattherestimefor
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whattherestimefor
| @@ -40,12 +40,12 @@ extension ReportSection { | |||
| return UITableViewDiffableDataSource(tableView: tableView) { tableView, indexPath, item -> UITableViewCell? in | |||
| switch item { | |||
| case .header(let headerContext): | |||
| let cell = tableView.dequeueReusableCell(withIdentifier: String(describing: ReportHeadlineTableViewCell.self), for: indexPath) as! ReportHeadlineTableViewCell | |||
| guard let cell = tableView.dequeueReusableCell(withIdentifier: String(describing: ReportHeadlineTableViewCell.self), for: indexPath) as? ReportHeadlineTableViewCell else { fatalError("WTF?! Wrong cell.") } | |||
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To avoid crashing in production, please use assertionFailure("unexpected cell dequeued") and then return nil.
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sure @whattherestimefor
| @@ -147,12 +166,15 @@ extension StatusSection { | |||
| return nil | |||
| case .option(let record): | |||
| // Fix cell reuse animation issue | |||
| let cell: PollOptionTableViewCell = { | |||
| guard let cell: PollOptionTableViewCell = { | |||
| let _cell = tableView.dequeueReusableCell(withIdentifier: String(describing: PollOptionTableViewCell.self) + "@\(indexPath.row)#\(indexPath.section)") as? PollOptionTableViewCell | |||
| _cell?.prepareForReuse() | |||
| return _cell ?? PollOptionTableViewCell() | |||
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This block will never return nil (if _cell is nil, it will create a new PollOptionTableViewCell()), so the else will never be reached. Best fix would be to remove the ?? PollOptionTableViewCell(), so that the block can return nil and the new else can then be reached.
| @@ -179,12 +201,15 @@ extension StatusSection { | |||
| return nil | |||
| case let .history(option): | |||
| // Fix cell reuse animation issue | |||
| let cell: PollOptionTableViewCell = { | |||
| guard let cell: PollOptionTableViewCell = { | |||
| let _cell = tableView.dequeueReusableCell(withIdentifier: String(describing: PollOptionTableViewCell.self) + "@\(indexPath.row)#\(indexPath.section)") as? PollOptionTableViewCell | |||
| _cell?.prepareForReuse() | |||
| return _cell ?? PollOptionTableViewCell() | |||
| @@ -218,6 +221,7 @@ extension UITableViewDelegate where Self: DataSourceProvider & MediaPreviewableV | |||
| parameters.visiblePath = UIBezierPath(roundedRect: mediaView.bounds, cornerRadius: MediaView.cornerRadius) | |||
| return UITargetedPreview(view: mediaView, parameters: parameters) | |||
| } else { | |||
| assertionFailure("unexpected cell dequeued") | |||
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This is not a dequeued cell being provided to populate the tableview, but rather a cell that is already in the tableview and is being accessed to learn things about its contents. The assertion could be something like "unexpected cell type at (indexPath)"
Issue: #1381
Description: