Author Archives: Oleksii

The issue I am going to talk about is relevant to anyone who uses Core Data. It is an “invisible” issue that may show up so rarely that it’s almost impossible to debug. It is only catchable by repeated automated tests. Let’s take a look at the piece of code that has single perform(_:) whichContinue reading “Your Core Data fetches may return unexpected results, or why you should use Query Generations”

So you can’t make Swift’s autogenerated initialize to be public. But at least there is a way to generate it using Xcode’s Refactor menu. Thanks JP Aquino https://stackoverflow.com/a/56530814/2774520

Have you ever encountered a file without extension, and wondered what is this file? I have, but thank to Jamie Wong and his great article “Reverse Engineering Instruments’ File Format”, this seem to not be a trouble anymore. Meet file – a program that tries to guess the type of a file by looking atContinue reading “TIL unix “file” program”

For AVVideoComposition to work correctly, you should init AVMutableVideoCompositionLayerInstruction with AVCompositionTrack created by you, instead of AVAssetTrack provided by AVAsset. This may be unintuitive at first, because how do you apply instructions to the track you want? How do you do transitions if there is only one AVCompositionTrack? Well, you’d create two, and alternate betweenContinue reading “AVMutableVideoCompositionLayerInstruction assetTrack”