[API Proposal]: Implement `IParsable<TSelf>` et cetera on `IPEndPoint`

[carlreinke]

Background and motivation

IPEndPoint has Parse methods. It should implement IParsable<TSelf> and the other interfaces that usually go with that.

API Proposal

Updated by @MihaZupan on 2025-05-20 to add all the methods

namespace System.Net;

public partial class IPEndPoint : EndPoint
+   , ISpanFormattable, ISpanParsable<IPEndPoint>, IUtf8SpanFormattable, IUtf8SpanParsable<SIPEndPoint>
{
    public static IPEndPoint Parse(ReadOnlySpan<char> s);
    public static IPEndPoint Parse(string s);
    public static bool TryParse(ReadOnlySpan<char> s, [NotNullWhen(true)] out IPEndPoint? result);
    public static bool TryParse(string s, [NotNullWhen(true)] out IPEndPoint? result);

+   public static IPEndPoint Parse(ReadOnlySpan<byte> utf8Text);
+   static IPEndPoint ISpanParsable<IPEndPoint>.Parse(ReadOnlySpan<char> s, IFormatProvider? provider);
+   static IPEndPoint IParsable<IPEndPoint>.Parse(string s, IFormatProvider? provider);
+   static IPEndPoint IUtf8SpanParsable<IPEndPoint>.Parse(ReadOnlySpan<byte> utf8Text, IFormatProvider? provider);

+   public static bool TryParse(ReadOnlySpan<byte> utf8Text, [NotNullWhen(true)] out IPEndPoint? result);
+   static bool ISpanParsable<IPEndPoint>.TryParse(ReadOnlySpan<char> s, IFormatProvider? provider, [NotNullWhen(true)] out IPEndPoint? result);
+   static bool IParsable<IPEndPoint>.TryParse([NotNullWhen(true)] string? s, IFormatProvider? provider, [NotNullWhen(true)] out IPEndPoint? result);
+   static bool IUtf8SpanParsable<IPEndPoint>.TryParse(ReadOnlySpan<byte> utf8Text, IFormatProvider? provider, [NotNullWhen(true)] out IPEndPoint? result);

+   string IFormattable.ToString(string? format, IFormatProvider? formatProvider);
+   public bool TryFormat(Span<char> destination, out int charsWritten);
+   public bool TryFormat(Span<byte> utf8Destination, out int bytesWritten);
+   bool ISpanFormattable.TryFormat(Span<char> destination, out int charsWritten, ReadOnlySpan<char> format, IFormatProvider? provider);
+   bool IUtf8SpanFormattable.TryFormat(Span<byte> utf8Destination, out int bytesWritten, ReadOnlySpan<char> format, IFormatProvider? provider);
}

API Usage

The type will be usable where generic type constraints require an IParsable<TSelf> or other of the added interfaces.

Alternative Designs

No response

Risks

No response

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[pentp]

Should also include IUtf8SpanFormattable, IUtf8SpanParsable<IPEndPoint> to match IPAddress.

[MihaZupan]

Updated the proposal with all the methods, mirroring IPAddress.
Format is ignored as with IPAddress, so those overloads are explicit instead.

Triage: Seems reasonable to match IPAddress here, also contributes to #81500 (comment). Making as ready for review, Future.

[bartonjs]

Video

• Looks consistent with how ISpanFormattable (et al) are implemented when the format parameter has no impact.
• Looks good as proposed

namespace System.Net;

public partial class IPEndPoint : EndPoint
+   , ISpanFormattable, ISpanParsable<IPEndPoint>, IUtf8SpanFormattable, IUtf8SpanParsable<IPEndPoint>
{
    public static IPEndPoint Parse(ReadOnlySpan<char> s);
    public static IPEndPoint Parse(string s);
    public static bool TryParse(ReadOnlySpan<char> s, [NotNullWhen(true)] out IPEndPoint? result);
    public static bool TryParse(string s, [NotNullWhen(true)] out IPEndPoint? result);

+   public static IPEndPoint Parse(ReadOnlySpan<byte> utf8Text);
+   static IPEndPoint ISpanParsable<IPEndPoint>.Parse(ReadOnlySpan<char> s, IFormatProvider? provider);
+   static IPEndPoint IParsable<IPEndPoint>.Parse(string s, IFormatProvider? provider);
+   static IPEndPoint IUtf8SpanParsable<IPEndPoint>.Parse(ReadOnlySpan<byte> utf8Text, IFormatProvider? provider);

+   public static bool TryParse(ReadOnlySpan<byte> utf8Text, [NotNullWhen(true)] out IPEndPoint? result);
+   static bool ISpanParsable<IPEndPoint>.TryParse(ReadOnlySpan<char> s, IFormatProvider? provider, [NotNullWhen(true)] out IPEndPoint? result);
+   static bool IParsable<IPEndPoint>.TryParse([NotNullWhen(true)] string? s, IFormatProvider? provider, [NotNullWhen(true)] out IPEndPoint? result);
+   static bool IUtf8SpanParsable<IPEndPoint>.TryParse(ReadOnlySpan<byte> utf8Text, IFormatProvider? provider, [NotNullWhen(true)] out IPEndPoint? result);

+   string IFormattable.ToString(string? format, IFormatProvider? formatProvider);
+   public bool TryFormat(Span<char> destination, out int charsWritten);
+   public bool TryFormat(Span<byte> utf8Destination, out int bytesWritten);
+   bool ISpanFormattable.TryFormat(Span<char> destination, out int charsWritten, ReadOnlySpan<char> format, IFormatProvider? provider);
+   bool IUtf8SpanFormattable.TryFormat(Span<byte> utf8Destination, out int bytesWritten, ReadOnlySpan<char> format, IFormatProvider? provider);
}