Blazor API Review: Render Frame types

[rynowak]

Summary

These are types that are used in the implementations of the renderer.

We want to keep these public so that it's possible to build new renderer implementations. The solution for this is to use an analyzer to mark these types as pubternal. This will be similar in ergonomics to #12066 or https://www.nuget.org/packages/Microsoft.CodeAnalysis.BannedApiAnalyzers/ but specific to Blazor with specific language about what/why these types should only be used in specific situations.

With this decision we're committing to:

• Not change the API surface in a patch
• Not change the API surface in a minor release

However we super expected to change this API surface in the next major release.

API

namespace Microsoft.AspNetCore.Components.Rendering
{
    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
    public readonly partial struct RenderBatch
    {
        private readonly object _dummy;
        public Microsoft.AspNetCore.Components.RenderTree.ArrayRange<int> DisposedComponentIDs { [System.Runtime.CompilerServices.CompilerGeneratedAttribute]get { throw null; } }
        public Microsoft.AspNetCore.Components.RenderTree.ArrayRange<int> DisposedEventHandlerIDs { [System.Runtime.CompilerServices.CompilerGeneratedAttribute]get { throw null; } }
        public Microsoft.AspNetCore.Components.RenderTree.ArrayRange<Microsoft.AspNetCore.Components.RenderTree.RenderTreeFrame> ReferenceFrames { [System.Runtime.CompilerServices.CompilerGeneratedAttribute]get { throw null; } }
        public Microsoft.AspNetCore.Components.RenderTree.ArrayRange<Microsoft.AspNetCore.Components.RenderTree.RenderTreeDiff> UpdatedComponents { [System.Runtime.CompilerServices.CompilerGeneratedAttribute]get { throw null; } }
    }
}
namespace Microsoft.AspNetCore.Components.RenderTree
{
    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
    public readonly partial struct ArrayBuilderSegment<T> : System.Collections.Generic.IEnumerable<T>, System.Collections.IEnumerable
    {
        private readonly object _dummy;
        private readonly int _dummyPrimitive;
        public T[] Array { get { throw null; } }
        public int Count { get { throw null; } }
        public T this[int index] { get { throw null; } }
        public int Offset { get { throw null; } }
        System.Collections.Generic.IEnumerator<T> System.Collections.Generic.IEnumerable<T>.GetEnumerator() { throw null; }
        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { throw null; }
    }
    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
    public readonly partial struct ArrayRange<T>
    {
        public readonly T[] Array;
        public readonly int Count;
        public ArrayRange(T[] array, int count) { throw null; }
        public Microsoft.AspNetCore.Components.RenderTree.ArrayRange<T> Clone() { throw null; }
    }
    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Sequential)]
    public readonly partial struct RenderTreeDiff
    {
        public readonly int ComponentId;
        public readonly Microsoft.AspNetCore.Components.RenderTree.ArrayBuilderSegment<Microsoft.AspNetCore.Components.RenderTree.RenderTreeEdit> Edits;
    }
    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Explicit)]
    public readonly partial struct RenderTreeEdit
    {
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int MoveToSiblingIndex;
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int ReferenceFrameIndex;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly string RemovedAttributeName;
        [System.Runtime.InteropServices.FieldOffsetAttribute(4)]
        public readonly int SiblingIndex;
        [System.Runtime.InteropServices.FieldOffsetAttribute(0)]
        public readonly Microsoft.AspNetCore.Components.RenderTree.RenderTreeEditType Type;
    }
    public enum RenderTreeEditType
    {
        PrependFrame = 1,
        RemoveFrame = 2,
        SetAttribute = 3,
        RemoveAttribute = 4,
        UpdateText = 5,
        StepIn = 6,
        StepOut = 7,
        UpdateMarkup = 8,
        PermutationListEntry = 9,
        PermutationListEnd = 10,
    }
    public enum RenderTreeFrameType : short
    {
        None = (short)0,
        Element = (short)1,
        Text = (short)2,
        Attribute = (short)3,
        Component = (short)4,
        Region = (short)5,
        ElementReferenceCapture = (short)6,
        ComponentReferenceCapture = (short)7,
        Markup = (short)8,
    }
    [System.Runtime.InteropServices.StructLayoutAttribute(System.Runtime.InteropServices.LayoutKind.Explicit)]
    public readonly partial struct RenderTreeFrame
    {
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int AttributeEventHandlerId;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly string AttributeName;
        [System.Runtime.InteropServices.FieldOffsetAttribute(24)]
        public readonly object AttributeValue;
        [System.Runtime.InteropServices.FieldOffsetAttribute(12)]
        public readonly int ComponentId;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly System.Action<object> ComponentReferenceCaptureAction;
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int ComponentReferenceCaptureParentFrameIndex;
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int ComponentSubtreeLength;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly System.Type ComponentType;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly string ElementName;
        [System.Runtime.InteropServices.FieldOffsetAttribute(24)]
        public readonly System.Action<Microsoft.AspNetCore.Components.ElementRef> ElementReferenceCaptureAction;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly string ElementReferenceCaptureId;
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int ElementSubtreeLength;
        [System.Runtime.InteropServices.FieldOffsetAttribute(4)]
        public readonly Microsoft.AspNetCore.Components.RenderTree.RenderTreeFrameType FrameType;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly string MarkupContent;
        [System.Runtime.InteropServices.FieldOffsetAttribute(8)]
        public readonly int RegionSubtreeLength;
        [System.Runtime.InteropServices.FieldOffsetAttribute(0)]
        public readonly int Sequence;
        [System.Runtime.InteropServices.FieldOffsetAttribute(16)]
        public readonly string TextContent;
        public Microsoft.AspNetCore.Components.IComponent Component { get { throw null; } }
        public override string ToString() { throw null; }
    }
}

[rynowak]

The only real decision I think we need to make here is whether to put the RenderBatch class in the .RenderTree namespace. I think this is a good change, because you're not likely to use RenderBatch without using those other types.