Percent encode, URLEncodedForm using FoundationEssentials

[adam-fowler]

• Replace percentDecode function with internal one removingURLPercentEncoding from FoundationEssentials
• Add addingPercentEncoding
• Use in URLEncodedForm code
• Replace ISO8601 date formatter with 6.0 Date format parser and style if available

And...

• Breaking change: remove URLEncodedFormDecoder.DateDecodingStrategy.formatted and equivalent URLEncodedFormEncoder version. This uses DateFormatter a pre swift 6.0 type. We cannot remove our dependency on Foundation without removing this. In theory we could add a HummingbirdFoundationCompat to include this in as it can be implemented with .custom in a similar way to how JSONEncoder does it.

    public static func formatted(_ formatter: DateFormatter) -> Self {
        .custom { decoder in
            let container = try decoder.singleValueContainer()
            let result = try container.decode(String.self)
            if let date = formatter.date(from: result) {
                return date
            } else {
                throw DecodingError.dataCorrupted(DecodingError.Context(codingPath: decoder.codingPath, debugDescription: "Date string does not match format expected by formatter."))
            }
        }
    }

[github-actions]

Pull request benchmark comparison [ubuntu-latest] with 'main' run at 2025-01-13T10:32:28+00:00

[Joannis]

Assuming this doesn't break older Apple OS'es, LGTM

[adam-fowler]

I've removed the breaking change, because I think it needs more discussion

[Cyberbeni]

@adam-fowler I think the breaking change issue could be resolved by introducing a new conditional compilation flag. So if people depend on this package and use swift build -Xswiftc -DFOUNDATION_ESSENTIALS_ONLY then they would build the version that only depends on FoundationEssentials but people who don't add this flag will continue to have the old API. Of course it would be nice for such a compilation flag to be unified across the whole swift-server ecosystem.

[adam-fowler]

@adam-fowler I think the breaking change issue could be resolved by introducing a new conditional compilation flag. So if people depend on this package and use swift build -Xswiftc -DFOUNDATION_ESSENTIALS_ONLY then they would build the version that only depends on FoundationEssentials but people who don't add this flag will continue to have the old API. Of course it would be nice for such a compilation flag to be unified across the whole swift-server ecosystem.

We have discussed used the SwiftPM traits support coming in Swift 6.1 for these kind of things