A quick followup about the AttributedString Codable conformance:
It already doesn't play well with snake case key coding strategy:
let input = AttributedString("Hello").settingAttributes(.init([.imageURL : URL(string: "https://example.com/")!]))
print("Before: ", input)
let encoder = JSONEncoder()
encoder.keyEncodingStrategy = .convertToSnakeCase
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
let encoded = try! encoder.encode(input)
print("Encoded: ", String(data: encoded, encoding: .utf8)!)
let decoded = try! decoder.decode(AttributedString.self, from: encoded)
print("After: ", decoded)
Outputs the following:
Before: Hello {
NSImageURL = https://example.com/
}
Encoded: ["Hello",{"n_s_image_url":{"relative":"https:\/\/example.com\/"}}]
After: Hello {
}
So it suffers from a similar (but not quite the same) issue as described above, but doesn't fail parsing - it just has an 'empty' attribute covering the "Hello" String.
I think that there may be some learning from this - I hope that I can formulate it clearly:
First of all my intuition about 'dynamic' keys still holds with this example: namely that it doesn't play well with key coding strategies.
Secondly: Is there a way to fix this? The only thing I can think of is a mechanism to explicitly opt-out from key coding strategies. You actually already get that when decoding dictionaries keyed by Strings - the keys are left alone. I suspect that dictionary decoding wouldn't work in this case, however, but perhaps we can think of another way to opt out of the key coding? Another 'marker' protocol on CodingKey, perhaps?