Support @bind:get, @bind:set, @bind:after

src/Microsoft.AspNetCore.Razor.Language/src/BoundAttributeDescriptorBuilderExtensions.cs

@@ -82,6 +82,16 @@ public static void SetPropertyName(this BoundAttributeParameterDescriptorBuilder
         builder.Metadata[TagHelperMetadata.Common.PropertyName] = propertyName;
     }
 
+    public static void SetBindAttributeGetSet(this BoundAttributeParameterDescriptorBuilder builder)
+    {
+        if (builder == null)
+        {
+            throw new ArgumentNullException(nameof(builder));
+        }
+
+        builder.Metadata[ComponentMetadata.Bind.BindAttributeGetSet] = bool.TrueString;
+    }    
+
     public static string GetPropertyName(this BoundAttributeParameterDescriptorBuilder builder)
     {
         if (builder == null)

src/Microsoft.AspNetCore.Razor.Language/src/ComponentResources.resx

@@ -129,6 +129,9 @@
   <data name="BindTagHelper_Component_Documentation" xml:space="preserve">
     <value>Binds the provided expression to the '{0}' property and a change event delegate to the '{1}' property of the component.</value>
   </data>
+  <data name="BindTagHelper_Element_After_Documentation" xml:space="preserve">
+    <value>Specifies an action to run after the new value has been set.</value>
+  </data>
   <data name="BindTagHelper_Element_Culture_Documentation" xml:space="preserve">
     <value>Specifies the culture to use for conversions.</value>
   </data>
@@ -141,6 +144,12 @@
   <data name="BindTagHelper_Element_Format_Documentation" xml:space="preserve">
     <value>Specifies a format to convert the value specified by the '{0}' attribute. The format string can currently only be used with expressions of type &lt;code&gt;DateTime&lt;/code&gt;.</value>
   </data>
+  <data name="BindTagHelper_Element_Get_Documentation" xml:space="preserve">
+    <value>Specifies the expression to use for binding the value to the attribute.</value>
+  </data>
+  <data name="BindTagHelper_Element_Set_Documentation" xml:space="preserve">
+    <value>Specifies the expression to use for updating the bound value when a new value is available.</value>
+  </data>
   <data name="BindTagHelper_Fallback_Documentation" xml:space="preserve">
     <value>Binds the provided expression to an attribute and a change event, based on the naming of the bind attribute. For example: &lt;code&gt;@bind-value="..."&lt;/code&gt; and &lt;code&gt;@bind-value:event="onchange"&lt;/code&gt; will assign the current value of the expression to the 'value' attribute, and assign a delegate that attempts to set the value to the 'onchange' attribute.</value>
   </data>

src/Microsoft.AspNetCore.Razor.Language/src/Components/ComponentDiagnosticFactory.cs

@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 #nullable disable
@@ -456,4 +456,97 @@ public static RazorDiagnostic CreateEventHandlerParameter_Duplicates(SourceSpan?
             Environment.NewLine + string.Join(Environment.NewLine, attributes.Select(p => p.TagHelper.DisplayName)));
         return diagnostic;
     }
+
+    public static readonly RazorDiagnosticDescriptor BindAttributeParameter_UseBindGet =
+        new RazorDiagnosticDescriptor(
+            $"{DiagnosticPrefix}10015",
+            () => "Attribute '{0}:get' must be used with attribute '{0}:set'.",
+            RazorDiagnosticSeverity.Error);
+
+
+    public static RazorDiagnostic CreateBindAttributeParameter_UseBindGet(SourceSpan? source, string attribute)
+    {
+        var diagnostic = RazorDiagnostic.Create(
+            BindAttributeParameter_UseBindGet,
+            source ?? SourceSpan.Undefined,
+            attribute);
+        return diagnostic;
+    }
+
+    public static readonly RazorDiagnosticDescriptor BindAttributeParameter_MissingBindGet =
+        new RazorDiagnosticDescriptor(
+            $"{DiagnosticPrefix}10016",
+            () => "Attribute '{0}:set' was used but no attribute '{0}:get' was found.",
+            RazorDiagnosticSeverity.Error);
+
+
+    public static RazorDiagnostic CreateBindAttributeParameter_MissingBindGet(SourceSpan? source, string attribute)
+    {
+        var diagnostic = RazorDiagnostic.Create(
+            BindAttributeParameter_MissingBindGet,
+            source ?? SourceSpan.Undefined,
+            attribute);
+        return diagnostic;
+    }
+
+    public static readonly RazorDiagnosticDescriptor BindAttribute_MissingBindSet =
+    new RazorDiagnosticDescriptor(
+    $"{DiagnosticPrefix}10017",
+    () => "The attribute '{0}' must have a companion '{1}' attribute.",
+    RazorDiagnosticSeverity.Error);
+
+    public static RazorDiagnostic CreateBindAttribute_MissingBindSet(SourceSpan? source, string attributeGet, string attributeSet)
+    {
+        var diagnostic = RazorDiagnostic.Create(
+            BindAttribute_MissingBindSet,
+            source ?? SourceSpan.Undefined,
+            attributeGet,
+            attributeSet);
+        return diagnostic;
+    }
+
+    public static readonly RazorDiagnosticDescriptor BindAttributeParameter_InvalidSyntaxBindAndBindGet =
+        new RazorDiagnosticDescriptor(
+        $"{DiagnosticPrefix}10018",
+        () => "Attribute '{0}' can't be used in conjunction with '{0}:get'.",
+        RazorDiagnosticSeverity.Error);
+
+    public static RazorDiagnostic CreateBindAttributeParameter_InvalidSyntaxBindAndBindGet(SourceSpan? source, string attribute)
+    {
+        var diagnostic = RazorDiagnostic.Create(
+            BindAttributeParameter_InvalidSyntaxBindAndBindGet,
+            source ?? SourceSpan.Undefined,
+            attribute);
+        return diagnostic;
+    }
+
+    public static readonly RazorDiagnosticDescriptor BindAttributeParameter_InvalidSyntaxBindSetAfter =
+        new RazorDiagnosticDescriptor(
+            $"{DiagnosticPrefix}10019",
+            () => "Attribute '{0}:after' can not be used with '{0}:set'. Invoke the code in '{0}:after' inside '{0}:set' instead.",
+            RazorDiagnosticSeverity.Error);
+
+    public static RazorDiagnostic CreateBindAttributeParameter_InvalidSyntaxBindSetAfter(SourceSpan? source, string attribute)
+    {
+        var diagnostic = RazorDiagnostic.Create(
+            BindAttributeParameter_InvalidSyntaxBindSetAfter,
+            source ?? SourceSpan.Undefined,
+            attribute);
+        return diagnostic;
+    }
+
+    public static readonly RazorDiagnosticDescriptor BindAttributeParameter_UnsupportedSyntaxBindGetSet =
+        new RazorDiagnosticDescriptor(
+        $"{DiagnosticPrefix}10020",
+        () => "Attribute '{0}' can only be used with RazorLanguageVersion 7.0 or higher.",
+        RazorDiagnosticSeverity.Error);
+
+    public static RazorDiagnostic CreateBindAttributeParameter_UnsupportedSyntaxBindGetSet(SourceSpan? source, string attribute)
+    {
+        var diagnostic = RazorDiagnostic.Create(
+            BindAttributeParameter_UnsupportedSyntaxBindGetSet,
+            source ?? SourceSpan.Undefined,
+            attribute);
+        return diagnostic;
+    }
 }

src/Microsoft.AspNetCore.Razor.Language/src/Components/ComponentMetadata.cs

@@ -49,6 +49,8 @@ public static class Bind
 
         public const string TagHelperKind = "Components.Bind";
 
+        public const string BindAttributeGetSet = "Components.Bind.AlternativeNotation";
+
         public const string FallbackKey = "Components.Bind.Fallback";
 
         public const string TypeAttribute = "Components.Bind.TypeAttribute";
@@ -91,6 +93,8 @@ public static class Component
 
         public const string DelegateSignatureKey = "Components.DelegateSignature";
 
+        public const string DelegateWithAwaitableResultKey = "Components.IsDelegateAwaitableResult";
+
         public const string EventCallbackKey = "Components.EventCallback";
 
         public const string WeaklyTypedKey = "Components.IsWeaklyTyped";

src/Microsoft.AspNetCore.Razor.Language/src/Components/ComponentsApi.cs

@@ -109,6 +109,8 @@ public static class RuntimeHelpers
     {
         public const string TypeCheck = "global::Microsoft.AspNetCore.Components.CompilerServices.RuntimeHelpers.TypeCheck";
         public const string CreateInferredEventCallback = "global::Microsoft.AspNetCore.Components.CompilerServices.RuntimeHelpers.CreateInferredEventCallback";
+        public const string InvokeSynchronousDelegate = "global::Microsoft.AspNetCore.Components.CompilerServices.RuntimeHelpers.InvokeSynchronousDelegate";
+        public const string InvokeAsynchronousDelegate = "global::Microsoft.AspNetCore.Components.CompilerServices.RuntimeHelpers.InvokeAsynchronousDelegate";
     }
 
     public static class RouteAttribute

src/Microsoft.AspNetCore.Razor.Language/src/Components/TagHelperBoundAttributeDescriptorExtensions.cs

@@ -17,6 +17,14 @@ public static bool IsDelegateProperty(this BoundAttributeDescriptor attribute)
             string.Equals(value, bool.TrueString);
     }
 
+    public static bool IsDelegateWithAwaitableResult(this BoundAttributeDescriptor attribute)
+    {
+        var key = ComponentMetadata.Component.DelegateWithAwaitableResultKey;
+        return
+            attribute.Metadata.TryGetValue(key, out var value) &&
+            string.Equals(value, bool.TrueString);
+    }
+
     /// <summary>
     /// Gets a value indicating whether the attribute is of type <c>EventCallback</c> or
     /// <c>EventCallback{T}</c>

src/Microsoft.AspNetCore.Razor.Language/src/Components/TagHelperDescriptorExtensions.cs

@@ -44,7 +44,7 @@ public static bool IsInputElementBindTagHelper(this TagHelperDescriptor tagHelpe
     {
         return
             tagHelper.IsBindTagHelper() &&
-            tagHelper.TagMatchingRules.Count == 1 &&
+            tagHelper.TagMatchingRules.Count == 2 &&
             string.Equals("input", tagHelper.TagMatchingRules[0].TagName);
     }
 

src/Microsoft.AspNetCore.Razor.Language/src/Intermediate/IntermediateNode.cs

@@ -1,4 +1,4 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 #nullable disable
@@ -58,7 +58,7 @@ private string Tree
         }
     }
 
-    private string DebuggerToString()
+    internal string DebuggerToString()
     {
         var formatter = new DebuggerDisplayFormatter();
         formatter.FormatNode(this);

src/Microsoft.AspNetCore.Razor.Language/src/Intermediate/IntermediateNodeReference.cs

@@ -1,13 +1,15 @@
-// Licensed to the .NET Foundation under one or more agreements.
+// Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
 #nullable disable
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 
 namespace Microsoft.AspNetCore.Razor.Language.Intermediate;
 
+[DebuggerDisplay($"{{{nameof(GetDebuggerDisplay)}(),nq}}")]
 public struct IntermediateNodeReference
 {
     public IntermediateNodeReference(IntermediateNode parent, IntermediateNode node)
@@ -207,4 +209,9 @@ public IntermediateNodeReference Replace(IntermediateNode node)
         Parent.Children[index] = node;
         return new IntermediateNodeReference(Parent, node);
     }
+
+    private string GetDebuggerDisplay()
+    {
+        return $"ref: {Parent.DebuggerToString()} - {Node.DebuggerToString()}";
+    }
 }

src/Microsoft.AspNetCore.Razor.Language/src/RazorLanguageVersion.cs

@@ -26,7 +26,9 @@ public sealed class RazorLanguageVersion : IEquatable<RazorLanguageVersion>, ICo
 
     public static readonly RazorLanguageVersion Version_6_0 = new RazorLanguageVersion(6, 0);
 
-    public static readonly RazorLanguageVersion Latest = Version_6_0;
+    public static readonly RazorLanguageVersion Version_7_0 = new RazorLanguageVersion(7, 0);
+
+    public static readonly RazorLanguageVersion Latest = Version_7_0;
 
     public static readonly RazorLanguageVersion Experimental = new RazorLanguageVersion(1337, 1337);
 
@@ -47,6 +49,11 @@ public static bool TryParse(string languageVersion, out RazorLanguageVersion ver
             version = Experimental;
             return true;
         }
+        else if (languageVersion == "7.0")
+        {
+            version = Version_7_0;
+            return true;
+        }
         else if (languageVersion == "6.0")
         {
             version = Version_6_0;

src/Microsoft.AspNetCore.Razor.Language/src/RazorProjectEngine.cs

@@ -254,7 +254,7 @@ private static void AddComponentFeatures(RazorProjectEngineBuilder builder, Razo
         builder.Features.Add(new ComponentKeyLoweringPass());
         builder.Features.Add(new ComponentReferenceCaptureLoweringPass());
         builder.Features.Add(new ComponentSplatLoweringPass());
-        builder.Features.Add(new ComponentBindLoweringPass());
+        builder.Features.Add(new ComponentBindLoweringPass(razorLanguageVersion.CompareTo(RazorLanguageVersion.Version_7_0) >= 0));
         builder.Features.Add(new ComponentCssScopePass());
         builder.Features.Add(new ComponentTemplateDiagnosticPass());
         builder.Features.Add(new ComponentGenericTypePass());

src/Microsoft.AspNetCore.Razor.Language/src/TagHelperDescriptor.cs

@@ -5,10 +5,12 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 
 namespace Microsoft.AspNetCore.Razor.Language;
 
+[DebuggerDisplay($"{{{nameof(GetDebuggerDisplay)}(),nq}}")]
 public abstract class TagHelperDescriptor : IEquatable<TagHelperDescriptor>
 {
     private IEnumerable<RazorDiagnostic> _allDiagnostics;
@@ -137,4 +139,9 @@ public ParsedTypeInformation(bool success, StringSegment @namespace, StringSegme
         public StringSegment Namespace { get; }
         public StringSegment TypeName { get; }
     }
+
+    private string GetDebuggerDisplay()
+    {
+        return $"{DisplayName} - {string.Join(" | ", TagMatchingRules.Select(r => r.GetDebuggerDisplay()))}";
+    }
 }

src/Microsoft.AspNetCore.Razor.Language/src/TagMatchingRuleDescriptor.cs

@@ -5,10 +5,12 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 
 namespace Microsoft.AspNetCore.Razor.Language;
 
+[DebuggerDisplay($"{{{nameof(GetDebuggerDisplay)}(),nq}}")]
 public abstract class TagMatchingRuleDescriptor : IEquatable<TagMatchingRuleDescriptor>
 {
     private int? _hashCode;
@@ -65,4 +67,29 @@ public override int GetHashCode()
         _hashCode ??= TagMatchingRuleDescriptorComparer.Default.GetHashCode(this);
         return _hashCode.Value;
     }
+
+    internal string GetDebuggerDisplay()
+    {
+        var tagName = TagName ?? "*";
+        tagName += TagStructure == TagStructure.WithoutEndTag ? "/" : "";
+        return $"{TagName ?? "*"}[{string.Join(", ", Attributes.Select(a => DescribeAttribute(a)))}]";
+        static string DescribeAttribute(RequiredAttributeDescriptor attribute)
+        {
+            var name = attribute.Name switch
+            {
+                null => "*",
+                var prefix when attribute.NameComparison == RequiredAttributeDescriptor.NameComparisonMode.PrefixMatch => $"^{prefix}",
+                var full => full,
+            };
+
+            var value = attribute.Value switch
+            {
+                null => "",
+                var prefix when attribute.ValueComparison == RequiredAttributeDescriptor.ValueComparisonMode.PrefixMatch => $"^={prefix}",
+                var suffix when attribute.ValueComparison == RequiredAttributeDescriptor.ValueComparisonMode.SuffixMatch => $"$={suffix}",
+                var full => $"={full}",
+            };
+            return name + value;
+        }
+    }
 }