swift: Partial block result builder fails to pick correct overload and generates compiler error

Description Partial block result builder fails to pick correct overload and generates a compiler error Ambiguous use of 'parser(of:)'

Steps to reproduce Paste the following code into a new project (This issue is a reduction of trying to compile an example (final 4 lines of the code below) of the swift-parsing package)

//MARK: Parsers
@rethrows public protocol Parser<Input> {
    associatedtype Input
}

extension String: Parser {
    public typealias Input = Substring
}

extension Int {
    static func parser(
        of inputType: Substring.Type = Substring.self
    ) -> FromSubstringToUTF8<IntParser<Substring.UTF8View>> {
        FromSubstringToUTF8 { IntParser<Substring.UTF8View>() }
    }

    static func parser(
        of inputType: Substring.UTF8View.Type = Substring.UTF8View.self
    ) -> IntParser<Substring.UTF8View> {
        .init()
    }
}

struct FromSubstringToUTF8<P: Parser>: Parser where P.Input == Substring.UTF8View {
    typealias Input = Substring
    
    let parser: P
    
    init(@ParserBuilder _ build: () -> P) { self.parser = build() }
}

struct IntParser<Input: Collection>: Parser where Input.SubSequence == Input, Input.Element == UTF8.CodeUnit {
    public init() { }
}

//MARK: ParserBuilder
struct Parse<Parsers: Parser>: Parser {
    typealias Input = Parsers.Input

    let parsers: Parsers
        
    init(@ParserBuilder with build: () -> Parsers) { self.parsers = build() }
}

@resultBuilder
struct ParserBuilder {
    public static func buildPartialBlock<P: Parser>(first: P) -> P { first }

    public static func buildPartialBlock<P0, P1>(accumulated: P0, next: P1) -> SkipFirst<P0, P1> {
        .init(p0: accumulated, p1: next)
    }
}

struct SkipFirst<P0: Parser, P1: Parser>: Parser where P0.Input == P1.Input {
    typealias Input = P0.Input

    let p0: P0
    let p1: P1
}

//MARK: main
let first = ParserBuilder.buildPartialBlock(first: ",")
let second = ParserBuilder.buildPartialBlock(accumulated: first, next: Int.parser())

let parser = Parse {
    ","
    Int.parser() // Ambiguous use of 'parser(of:)'
}

Expected behavior This compiles for toolchain 2023-01-02 but breaks from 2023-01-07. Expected to compile and choose the correct overload (in this case static func parser(of inputType: Substring.Type = Substring.self))

Since the first parser passed to the resultBuilder closure is of type String therefore the Parser associated type Input is of type Substring. Therefore the compiler should be able to infer that the parser returned by Int.parser() should have an Input of Substring as well.

Calling the individual partialBuildBlock functions does compile works:

let first = ParserBuilder.buildPartialBlock(first: ",")
let second = ParserBuilder.buildPartialBlock(accumulated: first, next: Int.parser())

fails:

let parser = Parse {
    ","
    Int.parser() // Ambiguous use of 'parser(of:)'
}

Environment

• Swift compiler version info Swift Development Snapshot 2023-01-09
• Xcode version info Xcode 13.4.1 Build version 13F100
• Deployment target: M1 running macOS 12.5