Deprecate IFunction.Expression

Author: adams85

src/Acornima.Extras/AstToJsonConverter.cs

@@ -578,7 +578,9 @@ private IFunction VisitFunction(IFunction node)
             Member("params", node.Params);
             Member("body", node.Body);
             Member("generator", node.Generator);
+#pragma warning disable CS0618 // Type or member is obsolete
             Member("expression", node.Expression);
+#pragma warning restore CS0618 // Type or member is obsolete
             Member("async", node.Async);
         }
 

src/Acornima/Ast/ArrowFunctionExpression.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Runtime.CompilerServices;
 
 namespace Acornima.Ast;
@@ -16,7 +17,9 @@ public ArrowFunctionExpression(
     {
         _params = parameters;
         Body = body;
+#pragma warning disable CS0618 // Type or member is obsolete
         Expression = expression;
+#pragma warning restore CS0618 // Type or member is obsolete
         Async = async;
     }
 
@@ -30,11 +33,14 @@ public ArrowFunctionExpression(
     /// </remarks>
     public StatementOrExpression Body { [MethodImpl(MethodImplOptions.AggressiveInlining)] get; }
     bool IFunction.Generator => false;
+    [Obsolete("This property is deprecated in the ESTree specification and therefore will be removed from the public API in a future major version.")]
     public bool Expression { [MethodImpl(MethodImplOptions.AggressiveInlining)] get; }
     public bool Async { [MethodImpl(MethodImplOptions.AggressiveInlining)] get; }
 
     private ArrowFunctionExpression Rewrite(in NodeList<Node> @params, StatementOrExpression body)
     {
+#pragma warning disable CS0618 // Type or member is obsolete
         return new ArrowFunctionExpression(@params, body, Expression, Async);
+#pragma warning restore CS0618 // Type or member is obsolete
     }
 }

src/Acornima/Ast/IFunction.cs

@@ -1,3 +1,5 @@
+using System;
+
 namespace Acornima.Ast;
 
 /// <summary>
@@ -8,6 +10,7 @@ public interface IFunction : INode
     Identifier? Id { get; }
     ref readonly NodeList<Node> Params { get; }
     StatementOrExpression Body { get; }
+    [Obsolete("This property is deprecated in the ESTree specification and therefore will be removed from the public API in a future major version.")]
     bool Expression { get; }
     bool Generator { get; }
     bool Async { get; }

test/Acornima.Tests/AstRewriterTests.cs

@@ -340,7 +340,9 @@ private T ForceNewObjectByControlType<T>(T node, Func<T, T> createNew)
     protected internal override object? VisitArrowFunctionExpression(ArrowFunctionExpression arrowFunctionExpression)
     {
         return ForceNewObjectByControlType((ArrowFunctionExpression)base.VisitArrowFunctionExpression(arrowFunctionExpression)!,
+#pragma warning disable CS0618 // Type or member is obsolete
             node => new ArrowFunctionExpression(node.Params, node.Body, node.Expression, node.Async));
+#pragma warning restore CS0618 // Type or member is obsolete
     }
 
     protected internal override object? VisitUnaryExpression(UnaryExpression unaryExpression)