Implemented very basic stacktrace

Upsilon/BaseTypes/ScriptFunction/ScriptFunction.cs

@@ -6,8 +6,11 @@ namespace Upsilon.BaseTypes.ScriptFunction
 {
     public abstract class ScriptFunction : ScriptType
     {
-        protected ScriptFunction(bool isCoroutine)
+        public string Name { get; protected set; }
+
+        protected ScriptFunction(string name, bool isCoroutine)
         {
+            Name = name;
             IsCoroutine = isCoroutine;
         }
 
@@ -24,7 +27,7 @@ namespace Upsilon.BaseTypes.ScriptFunction
 
         public bool IsCoroutine { get; }
 
-        public abstract ScriptType Run(Diagnostics diagnostics, ScriptType[] variables, Script script, EvaluationScope scope, TextSpan span);
+        public abstract ScriptType Run(Diagnostics diagnostics, ScriptType[] variables, EvaluationScope scope, TextSpan span, EvaluationState state);
-        public abstract IEnumerator RunCoroutine(Diagnostics diagnostics, ScriptType[] variables, Script script, EvaluationScope scope, TextSpan span);
+        public abstract IEnumerator RunCoroutine(Diagnostics diagnostics, ScriptType[] variables, EvaluationScope scope, TextSpan span, EvaluationState state);
     }
 }

Upsilon/BaseTypes/ScriptFunction/ScriptMethodInfoFunction.cs

@@ -14,7 +14,7 @@ namespace Upsilon.BaseTypes.ScriptFunction
     public class ScriptMethodInfoFunction : ScriptFunction
     {
         public ScriptMethodInfoFunction(UserDataMethod method, object o, bool directTypeManipulation,
-            bool isCoroutine, bool passScriptReference = false, bool passScopeReference = false) : base(isCoroutine)
+            bool isCoroutine, bool passScriptReference = false, bool passScopeReference = false) : base(method.Name, isCoroutine)
         {
             Method                 = method;
             _object                 = o;
@@ -46,33 +46,38 @@ namespace Upsilon.BaseTypes.ScriptFunction
             return Method.GetMethods().First().Parameters;
         }
 
-        public override ScriptType Run(Diagnostics diagnostics, ScriptType[] variables, Script script, EvaluationScope scope, TextSpan span)
+        public override ScriptType Run(Diagnostics diagnostics, ScriptType[] variables, EvaluationScope scope, TextSpan span, EvaluationState state)
         {
-            var result = Execute(diagnostics, variables, script, scope, span);
+            state.Stacktrace.Push(this);
+            var result = Execute(variables, state.Script, scope, span);
+            state.Stacktrace.Pop();
             if (_directTypeManipulation)
                 return (ScriptType)result;
             return result.ToScriptType();
 
         }
 
-        public override IEnumerator RunCoroutine(Diagnostics diagnostics, ScriptType[] variables, Script script, EvaluationScope scope,
+        public override IEnumerator RunCoroutine(Diagnostics diagnostics, ScriptType[] variables, EvaluationScope scope,
-            TextSpan span)
+            TextSpan span , EvaluationState state)
         {
-            var result = Execute(diagnostics, variables, script, scope, span);
+            state.Stacktrace.Push(this);
+            var result = Execute(variables, state.Script, scope, span);
             if (result is IEnumerator enumerator)
             {
                 while (enumerator.MoveNext())
                 {
                     yield return enumerator.Current;
                 }
+                state.Stacktrace.Pop();
                 yield break;
             }
             yield return result;
+            state.Stacktrace.Pop();
         }
 
-        private object Execute(Diagnostics diagnostics, ScriptType[] variables, Script script, EvaluationScope scope, TextSpan span)
+        private object Execute(IEnumerable<ScriptType> variables, Script script, EvaluationScope scope, TextSpan span)
         {
-                        var objects = new List<object>();
+            var objects = new List<object>();
             if (_passScriptReference)
                 objects.Add(script);
             if (_passScopeReference)
@@ -132,9 +137,9 @@ namespace Upsilon.BaseTypes.ScriptFunction
                     // if we haven't found a method, we throw an exception
                     if (method == null)
                     {
-                        throw new ScriptRuntimeException(script.FileName,
+                        throw new EvaluationException(script.FileName,
                             $"Can't find method {Method.Name} with parameter types {string.Join(", ", convertedTypes.Select(x => x.Name))} on type {_object.GetType().Name}",
-                            span, diagnostics.ScriptString.GetSpan(span));
+                            span);
                     }
                     // get the method parameters
                     var parameters = method.GetParameters();

Upsilon/BaseTypes/ScriptFunction/ScriptRuntimeFunction.cs

@@ -16,37 +16,46 @@ namespace Upsilon.BaseTypes.ScriptFunction
     {
         public List<ScriptRuntimeFunctionOption> Options { get; }
 
-        public ScriptRuntimeFunction(List<ScriptRuntimeFunctionOption> options, bool isCoroutine) : base(isCoroutine)
+        public ScriptRuntimeFunction(string name, List<ScriptRuntimeFunctionOption> options, bool isCoroutine) : base(name, isCoroutine)
         {
             Options = options;
         }
 
-        public override ScriptType Run(Diagnostics diagnostics, ScriptType[] variables, Script script,
+        public void SetName(string name)
-            EvaluationScope scope, TextSpan span)
         {
-            var option = GetValidOption(variables);
+            Name = name;
-            if (option == null)
-            {
-                throw new EvaluationException(script.FileName,
-                    $"No valid function found", span);
-            }
-            return option.Run(diagnostics, variables, script, scope, span);
         }
 
-        public override IEnumerator RunCoroutine(Diagnostics diagnostics, ScriptType[] variables, Script script, EvaluationScope scope,
+        public override ScriptType Run(Diagnostics diagnostics, ScriptType[] variables, EvaluationScope scope, TextSpan span, EvaluationState state)
-            TextSpan span)
         {
             var option = GetValidOption(variables);
             if (option == null)
             {
-                throw new EvaluationException(script.FileName,
+                throw new EvaluationException(state.Script.FileName,
                     $"No valid function found", span);
             }
-            var coroutine = option.RunCoroutine(diagnostics, variables, script, scope, span);
+            state.Stacktrace.Push(this);
+            var result = option.Run(diagnostics, variables, state.Script, scope, span);
+            state.Stacktrace.Pop();
+            return result;
+        }
+
+        public override IEnumerator RunCoroutine(Diagnostics diagnostics, ScriptType[] variables, EvaluationScope scope,
+            TextSpan span, EvaluationState state)
+        {
+            var option = GetValidOption(variables);
+            if (option == null)
+            {
+                throw new EvaluationException(state.Script.FileName,
+                    $"No valid function found", span);
+            }
+            state.Stacktrace.Push(this);
+            var coroutine = option.RunCoroutine(diagnostics, variables, state.Script, scope, span);
             while (coroutine.MoveNext())
             {
                 yield return coroutine.Current;
             }
+            state.Stacktrace.Pop();
         }
 
         public ScriptRuntimeFunctionOption GetValidOption(object[] variables)

Upsilon/Binder/BoundExpressions/BoundBinaryExpression.cs

@@ -149,36 +149,32 @@ namespace Upsilon.Binder
                         return ((ScriptNumber) left) < ((ScriptNumber) right);
                     }
 
-                    throw new ScriptRuntimeException(state.Script.FileName,
+                    throw new EvaluationException(state.Script.FileName,
-                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span,
+                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span);
-                        diagnostics.ScriptString.GetSpan(Span));
                 case BoundBinaryOperator.OperatorKind.LessEquals:
                     if (left.Type == Type.Number && right.Type == Type.Number)
                     {
                         return ((ScriptNumber) left) <= ((ScriptNumber) right);
                     }
 
-                    throw new ScriptRuntimeException(state.Script.FileName,
+                    throw new EvaluationException(state.Script.FileName,
-                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span,
+                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span);
-                        diagnostics.ScriptString.GetSpan(Span));
                 case BoundBinaryOperator.OperatorKind.Greater:
                     if (left.Type == Type.Number && right.Type == Type.Number)
                     {
                         return ((ScriptNumber) left) > ((ScriptNumber) right);
                     }
 
-                    throw new ScriptRuntimeException(state.Script.FileName,
+                    throw new EvaluationException(state.Script.FileName,
-                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span,
+                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span);
-                        diagnostics.ScriptString.GetSpan(Span));
                 case BoundBinaryOperator.OperatorKind.GreaterEquals:
                     if (left.Type == Type.Number && right.Type == Type.Number)
                     {
                         return ((ScriptNumber) left) >= ((ScriptNumber) right);
                     }
 
-                    throw new ScriptRuntimeException(state.Script.FileName,
+                    throw new EvaluationException(state.Script.FileName,
-                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span,
+                        $"Can't find operator '{Operator.Kind}' for types '{left.Type}' and '{right.Type}'", Span);
-                        diagnostics.ScriptString.GetSpan(Span));
                 default:
                     throw new Exception("Invalid Binary Operator: " + Operator.Kind);
             }

Upsilon/Binder/BoundExpressions/BoundFunctionCallExpression.cs

@@ -48,7 +48,7 @@ namespace Upsilon.Binder
                 ls.Add(evaluate);
             }
 
-            var val = function.Run(diagnostics, ls.ToArray(), state.Script, scope, Span);
+            var val = function.Run(diagnostics, ls.ToArray(), scope, Span, state);
             return val;
         }
     }

Upsilon/Binder/BoundExpressions/BoundFunctionExpression.cs

@@ -40,7 +40,7 @@ namespace Upsilon.Binder
         internal override ScriptType Evaluate(EvaluationScope scope, Diagnostics diagnostics, ref EvaluationState state)
         {
             var option = new ScriptRuntimeFunction.ScriptRuntimeFunctionOption(Parameters, Block, scope);
-            var func = new ScriptRuntimeFunction(new List<ScriptRuntimeFunction.ScriptRuntimeFunctionOption>() {option},
+            var func = new ScriptRuntimeFunction("<anonymous>", new List<ScriptRuntimeFunction.ScriptRuntimeFunctionOption>() {option},
                 IsCoroutine);
             return func;
 

Upsilon/Binder/BoundStatements/BoundFunctionAssignmentStatement.cs

@@ -28,6 +28,7 @@ namespace Upsilon.Binder
         internal override void Evaluate(EvaluationScope scope, Diagnostics diagnostics, ref EvaluationState state)
         {
             var func = (ScriptRuntimeFunction)Func.Evaluate(scope, diagnostics, ref state);
+            func.SetName(Variable.Name);
             if (Variable.Local)
             {
                 if (scope.Variables.TryGetValue(Variable.Name, out var f) && f is ScriptRuntimeFunction scriptRuntimeFunction)

Upsilon/Binder/BoundStatements/BoundYieldStatement.cs

@@ -27,9 +27,8 @@ namespace Upsilon.Binder
 
         internal override void Evaluate(EvaluationScope scope, Diagnostics diagnostics, ref EvaluationState state)
         {
-            throw new ScriptRuntimeException(state.Script.FileName,
+            throw new EvaluationException(state.Script.FileName,
-                "Yielding in a function that's not executed as a coroutine is not possible.", Span,
+                "Yielding in a function that's not executed as a coroutine is not possible.", Span);
-                diagnostics.ScriptString.GetLine(Span.StartLine));
         }
 
         internal override IEnumerator EvaluateCoroutine(EvaluationScope scope, Diagnostics diagnostics, EvaluationState state)
@@ -51,7 +50,7 @@ namespace Upsilon.Binder
                         var evaluate = t.Evaluate(scope, diagnostics, ref state);
                         ls.Add(evaluate);
                     }
-                    var coroutine = function.RunCoroutine(diagnostics, ls.ToArray(), state.Script, scope, Span);
+                    var coroutine = function.RunCoroutine(diagnostics, ls.ToArray(), scope, Span, state);
                     while (coroutine.MoveNext())
                     {
                         yield return coroutine.Current;

Upsilon/Evaluator/EvaluationState.cs

@@ -2,12 +2,13 @@ using Upsilon.BaseTypes;
 
 namespace Upsilon.Evaluator
 {
-    internal class EvaluationState
+    public class EvaluationState
     {
         public Script Script;
         public bool Returned;
         public bool HasBroken;
         public ScriptType ReturnValue;
+        public Stacktrace Stacktrace = new Stacktrace();
         public ScriptType LastValue;
     }
 }

Upsilon/Evaluator/Stacktrace.cs

@@ -0,0 +1,26 @@
+using System.Collections.Generic;
+using System.Linq;
+using Upsilon.BaseTypes.ScriptFunction;
+
+namespace Upsilon.Evaluator
+{
+    public class Stacktrace
+    {
+        private readonly Stack<ScriptFunction> _stack = new Stack<ScriptFunction>();
+
+        public void Push(ScriptFunction statement)
+        {
+            _stack.Push(statement);
+        }
+
+        public ScriptFunction Pop()
+        {
+            return _stack.Pop();
+        }
+
+        public IEnumerable<ScriptFunction> GetTopStack(int i)
+        {
+            return _stack.Take(i);
+        }
+    }
+}

Upsilon/Exceptions/EvaluationException.cs

@@ -1,16 +1,20 @@
 using System;
+using System.Text;
+using Upsilon.Evaluator;
 using Upsilon.Text;
 
 namespace Upsilon.Exceptions
 {
     public class EvaluationException : Exception
     {
+        private readonly Stacktrace _stacktrace;
         public string FileName { get; }
         public string ErrorMessage { get; }
         public TextSpan Span { get; }
 
-        public EvaluationException(string fileName, string message, TextSpan span)
+        public EvaluationException(string fileName, string message, TextSpan span, Stacktrace stacktrace = null)
         {
+            _stacktrace = stacktrace;
             FileName = fileName;
             ErrorMessage = message;
             Span = span;
@@ -18,7 +22,15 @@ namespace Upsilon.Exceptions
 
         public override string ToString()
         {
-            return $"[{FileName}] ({Span.StartLine},{Span.StartPosition}) {ErrorMessage}";
+            var err = new StringBuilder($"[{FileName}] ({Span.StartLine},{Span.StartPosition}) {ErrorMessage}");
+            if (_stacktrace != null)
+            {
+                foreach (var statement in _stacktrace.GetTopStack(10))
+                {
+                    err.Append($"\n{statement.Name}");
+                }
+            }
+            return err.ToString();
         }
 
         public override string Message => ToString();

Upsilon/Exceptions/ScriptRuntimeException.cs

@@ -1,30 +0,0 @@
-using System;
-using Upsilon.Text;
-
-namespace Upsilon.Exceptions
-{
-    public class ScriptRuntimeException : Exception
-    {
-        public string FileName { get; }
-        public string ErrorMessage { get; }
-        public int    Line         { get; }
-        public int    Character    { get; }
-        public string ErrorLine    { get; }
-
-        public ScriptRuntimeException(string fileName, string errorMessage, TextSpan position, string errorLine)
-        {
-            FileName = fileName;
-            ErrorMessage = errorMessage;
-            Line         = position.StartLine;
-            Character    = position.StartPosition;
-            ErrorLine    = errorLine;
-        }
-
-        public override string ToString()
-        {
-            return $"[{FileName}] {ErrorMessage} at ({Line}, {Character})\n{ErrorLine}";
-        }
-
-        public override string Message => ToString();
-    }
-}