Enable Intercept function call

Jint.Tests/Runtime/InteropTests.cs

@@ -2,6 +2,7 @@
 using System.Globalization;
 using System.Reflection;
 using System.Runtime.CompilerServices;
+using Esprima.Ast;
 using Jint.Native;
 using Jint.Native.Object;
 using Jint.Native.Symbol;
@@ -3251,5 +3252,62 @@ public void CanPassDateTimeMinAndMaxViaInterop()
             engine.Execute("capture(maxDate);");
             Assert.Equal(DateTime.MaxValue, dt);
         }
+
+        [Fact]
+        public void CanInterceptFunctionCallViaInterop()
+        {
+            var records = new Dictionary<Guid, FunctionCallRecord>();
+            var engine = new Engine(cfg =>
+            {
+                cfg.Interop.FunctionExecuting = ctx =>
+                {
+                    var location = ((Node) ctx.Function).Location;
+                    var record = new FunctionCallRecord
+                    {
+                        Name = ctx.Function.Id?.Name,
+                        StartLine = location.Start.Line,
+                        EndLine = location.End.Line,
+                        Args = ctx.Arguments.Select(x => x.ToObject()).ToArray()
+                    };
+                    records.Add(ctx.UniqueId, record);
+                };
+                cfg.Interop.FunctionExecuted = ctx =>
+                {
+                    if (records.TryGetValue(ctx.UniqueId, out var record) && ctx.Result is { Type: CompletionType.Return })
+                    {
+                        record.Result = ctx.Result.Value.Value.ToObject();
+                    }
+                };
+            });
+            const string Js = @"
+function main() {
+    return add(1, 2);
+}
+function add(a, b) {
+    return a + b;
+}";
+            var script = Engine.PrepareScript(Js.TrimStart());
+            engine.Execute(script);
+            var result = engine.Invoke("main").ToObject();
+            Assert.Equal(3, Convert.ToInt32(result));
+            var traces = records.Values.ToList();
+            Assert.Equal(2, traces.Count);
+            Assert.Equal("main", traces[0].Name);
+            Assert.Equal(3, Convert.ToInt32(traces[0].Result));
+            Assert.Equal(2, traces[1].Args.Length);
+            Assert.Equal(1, Convert.ToInt32(traces[1].Args[0]));
+            Assert.Equal(2, Convert.ToInt32(traces[1].Args[1]));
+            Assert.Equal(1, traces[0].StartLine);
+            Assert.Equal(3, traces[0].EndLine);
+        }
+
+        private class FunctionCallRecord
+        {
+            public string Name { get; set; }
+            public int StartLine { get; set; }
+            public int EndLine { get; set; }
+            public object[] Args { get; set; }
+            public object Result { get; set; }
+        }
     }
 }

Jint/Options.cs

@@ -5,11 +5,12 @@
 using Jint.Native;
 using Jint.Native.Object;
 using Jint.Runtime;
-using Jint.Runtime.Interop;
+using Jint.Runtime.CallStack;
 using Jint.Runtime.Debugger;
 using Jint.Runtime.Descriptors;
+using Jint.Runtime.Interop;
+using Jint.Runtime.Interop.Function;
 using Jint.Runtime.Modules;
-using Jint.Runtime.CallStack;
 
 namespace Jint
 {
@@ -19,6 +20,10 @@ namespace Jint
 
     public delegate bool ExceptionHandlerDelegate(Exception exception);
 
+    public delegate void FunctionExecutingDelegate(FunctionExecutionContext context);
+
+    public delegate void FunctionExecutedDelegate(FunctionExecutionContext context);
+
     public class Options
     {
         private ITimeSystem? _timeSystem;
@@ -334,6 +339,10 @@ public class InteropOptions
         /// </summary>
         public Func<object, string>? SerializeToJson { get; set; }
 
+        public FunctionExecutingDelegate? FunctionExecuting { get; set; }
+
+        public FunctionExecutedDelegate? FunctionExecuted { get; set; }
+
         /// <summary>
         /// What kind of date time should be produced when JavaScript date is converted to DateTime. If Local, uses <see cref="Options.TimeZone"/>.
         /// Defaults to <see cref="System.DateTimeKind.Utc"/>.

Jint/Runtime/Interop/Function/FunctionExecutionContext.cs

@@ -0,0 +1,17 @@
+using Esprima.Ast;
+using Jint.Native;
+using Jint.Native.Function;
+
+#nullable disable
+
+namespace Jint.Runtime.Interop.Function;
+
+public class FunctionExecutionContext
+{
+    public Guid UniqueId { get; set; }
+    public Engine Engine { get; set; }
+    public IFunction Function { get; set; }
+    public FunctionInstance FunctionInstance { get; set; }
+    public JsValue[] Arguments { get; set; }
+    public Completion? Result { get; set; }
+}

Jint/Runtime/Interpreter/JintFunctionDefinition.cs

@@ -1,10 +1,12 @@
 using System.Runtime.CompilerServices;
+using Esprima;
 using Esprima.Ast;
 using Jint.Native;
 using Jint.Native.Argument;
 using Jint.Native.Function;
 using Jint.Native.Promise;
 using Jint.Runtime.Environments;
+using Jint.Runtime.Interop.Function;
 using Jint.Runtime.Interpreter.Expressions;
 
 namespace Jint.Runtime.Interpreter;
@@ -38,6 +40,19 @@ internal Completion EvaluateBody(EvaluationContext context, FunctionInstance fun
     {
         Completion result;
         ArgumentsInstance? argumentsInstance = null;
+        FunctionExecutionContext? executionContext = null;
+        if (context.Engine.Options.Interop.FunctionExecuting is not null)
+        {
+            executionContext = new FunctionExecutionContext
+            {
+                Engine = context.Engine,
+                FunctionInstance = functionObject,
+                Function = Function,
+                Arguments = argumentsList,
+                UniqueId = Guid.NewGuid()
+            };
+            context.Engine.Options.Interop.FunctionExecuting(executionContext);
+        }
         if (Function.Expression)
         {
             // https://tc39.es/ecma262/#sec-runtime-semantics-evaluateconcisebody
@@ -90,6 +105,20 @@ internal Completion EvaluateBody(EvaluationContext context, FunctionInstance fun
         }
 
         argumentsInstance?.FunctionWasCalled();
+
+        if (context.Engine.Options.Interop.FunctionExecuted is not null)
+        {
+            executionContext ??= new FunctionExecutionContext()
+            {
+                Engine = context.Engine,
+                Function = Function,
+                FunctionInstance = functionObject,
+                Arguments = argumentsList,
+                UniqueId = Guid.NewGuid()
+            };
+            executionContext.Result = result;
+            context.Engine.Options.Interop.FunctionExecuted(executionContext);
+        }
         return result;
     }
 
@@ -415,7 +444,7 @@ private static void ProcessParameters(
         out bool hasArguments)
     {
         hasArguments = false;
-        state.IsSimpleParameterList  = true;
+        state.IsSimpleParameterList = true;
 
         var countParameters = true;
         ref readonly var functionDeclarationParams = ref function.Params;