tests fail to build with Xcode 15.3

[dave256]

I assume these tests built before but with Xcode 15.3, the Swift compiler fails with compiler issues:

swift-parsing/Sources/swift-parsing-benchmark/JSON.swift:71:84 Failed to produce diagnostic for expression; please submit a bug report (https://swift.org/contributing/#reporting-bugs)

swift-parsing/Tests/ParsingTests/OneOfTests.swift:272:86 Failed to produce diagnostic for expression; please submit a bug report (https://swift.org/contributing/#reporting-bugs)

I did not file a bug at swift.org as I didn't feel I could narrow it down.

[cham-s]

I'm not sure why but in this version of XCode the compiler is not able to infer the type compare to the previous versions.
A possible fix is to provide more type information to help the compiler.
But it makes the code more verbose.

For instance in

• Sources/swift-parsing-benchmark/JSON.swift

We can add more type information on the JSONObject Parser:

//Before
struct JSONObject: ParserPrinter {
  var body: some ParserPrinter<Substring.UTF8View, [String: JSONValue.Output]> {
    "{".utf8
    Many(into: [String: JSONValue.Output]()) { object, pair in
      let (name, value) = pair
      object[name] = value
    } decumulator: { object in
      (object.sorted(by: { $0.key < $1.key }) as [(String, JSONValue.Output)])
        .reversed()
        .makeIterator()
    } element: {
      Whitespace()
      JSONString()
      Whitespace()
      ":".utf8
      JSONValue()
    } separator: {
      ",".utf8
    } terminator: {
      "}".utf8
    }
  }
}

// After
struct JSONObject: ParserPrinter {
  var body: some ParserPrinter<Substring.UTF8View, [String: JSONValue.Output]> {
    "{".utf8
    Many(into: [String: JSONValue.Output]()) { (
      object: inout [String: JSONValue.Output],
      pair: (String, JSONValue.Output)
    ) in
      let (name, value) = pair
      object[name] = value
    } decumulator: { object in
      (object.sorted(by: { $0.key < $1.key }) as [(String, JSONValue.Output)])
        .reversed()
        .makeIterator()
    } element: {
      Whitespace()
      JSONString()
      Whitespace()
      ":".utf8
      JSONValue()
    } separator: {
      ",".utf8
    } terminator: {
      "}".utf8
    }
  }
}

I have submitted a pull request for this.

[dave256]

Thanks. I wondered it was an issue with the compiler not being able to infer types. I used to see that error years ago with Swift but haven't seen it recently. @cham-s thanks for submitting a pull request.