loading other scripts from a single script

UndertaleModCli/Program.cs

@@ -721,7 +721,8 @@
 
         try
         {
-            CSharpScript.EvaluateAsync(code, CliScriptOptions, this, typeof(IScriptInterface)).GetAwaiter().GetResult();
+            var processedCode = ScriptUtil.ProcessScriptText(code, scriptFile);
+            CSharpScript.EvaluateAsync(processedCode, CliScriptOptions, this, typeof(IScriptInterface)).GetAwaiter().GetResult();
             ScriptExecutionSuccess = true;
             ScriptErrorMessage = "";
         }
@@ -729,7 +730,7 @@
         {
             ScriptExecutionSuccess = false;
             ScriptErrorMessage = exc.ToString();
             ScriptErrorType = "Exception";
         }
 
         if (!FinishedMessageEnabled) return;

UndertaleModLib/Util/ScriptUtil.cs

@@ -0,0 +1,37 @@
+using System.IO;
+using System.Text.RegularExpressions;
+
+namespace UndertaleModLib.Util
+{
+    /// <summary>
+    /// Utils related to running scripts
+    /// </summary>
+    public static class ScriptUtil
+    {
+        /// <summary>
+        /// Processes a script text so that it can use relative `#load` preprocessing
+        /// </summary>
+        /// <param name="code">The script code</param>
+        /// <param name="path">The path to the script</param>
+        /// <returns></returns>
+        public static string ProcessScriptText(string code, string path)
+        {
+            var output = code;
+            // since attempting to load scripts with #load in a file will lead to it using the UTMT path,
+            // we can circumvent this by hardcoding the absolute path to the script directory
+            // in all instances of #load with a relative path
+            var scriptDir = Path.GetDirectoryName(path);
+            var matches = Regex.Matches(code, @"(?<=^#load\s+"").*\.csx(?=""\s*$)", RegexOptions.Multiline);
+            foreach (Match match in matches)
+            {
+                if (Path.IsPathRooted(match.Value))
+                {
+                    continue;
+                }
+                output = output.Replace(match.Value, Path.Combine(scriptDir, match.Value));
+            }
+
+            return output;
+        }
+    }
+}

UndertaleModTool/MainWindow.xaml.cs

@@ -2467,9 +2467,10 @@
             }
         }
 
-        public string ProcessException(in Exception exc, in string scriptText)
+        public string ProcessException(in Exception exc)
         {
-            List<int> excLineNums = new();
+            // each member is a (file name, line number) pair for all lines in the stack trace
+            List<Tuple<string, int>> loadedScriptLineNums = new();
             string excText = string.Empty;
             List<string> traceLines = new();
             Dictionary<string, int> exTypesDict = null;
@@ -2505,12 +2506,15 @@
                 {
                     if (traceLine.TrimStart()[..13] == "at Submission") // only stack trace lines from the script
                     {
+                        // matches full path of the script file
+                        string sourceFile = Regex.Match(traceLine, @"(?<=in ).*\.csx(?=:line \d+)").Value;
+                        if (!File.Exists(sourceFile))
+                            continue;
                         int linePos = traceLine.IndexOf(":line ") + 6;  // ":line ".Length = 6
                         if (linePos != (-1 + 6))
                         {
                             int lineNum = Convert.ToInt32(traceLine[linePos..]);
-                            if (!excLineNums.Contains(lineNum))
-                                excLineNums.Add(lineNum);
+                            loadedScriptLineNums.Add(new Tuple<string, int>(sourceFile, lineNum));
                         }
                     }
                 }
@@ -2526,10 +2530,35 @@
                 return $"An error occurred while processing the exception text.\nError message - \"{e.Message}\"\nThe unprocessed text is below.\n\n" + excString;
             }
 
-            if (excLineNums.Count > 0) //if line number(s) is found
+            if (loadedScriptLineNums.Count > 0) //if line number(s) is found
             {
-                string[] scriptLines = scriptText.Split('\n');
-                string excLines = string.Join('\n', excLineNums.Select(n => $"Line {n}: {scriptLines[n].TrimStart(new char[] { '\t', ' ' })}"));
+                // read the code for the files to know what the code line associated with the stack trace is
+                Dictionary<string, List<string>> scriptsCode = new();
+                foreach (Tuple<string, int> scriptLineNum in loadedScriptLineNums)
+                {
+                    string scriptPath = scriptLineNum.Item1;
+                    if (!scriptsCode.ContainsKey(scriptPath))
+                    {
+                        string scriptCode = null;
+                        try
+                        {
+                            scriptCode = File.ReadAllText(scriptPath);
+                        }
+                        catch (Exception e)
+                        {
+                            string excString = exc.ToString();
+
+                            return $"An error occurred while processing the exception text.\nError message - \"{e.Message}\"\nThe unprocessed text is below.\n\n" + excString;
+                        }
+                        scriptsCode.Add(scriptPath, scriptCode.Split('\n').ToList());
+                    }
+                }
+
+                string excLines = string.Join('\n', loadedScriptLineNums.Select(pair => 
+                {
+                    string scriptName = pair.Item1.Split(Path.DirectorySeparatorChar)[^1];
+                    return $"Line {pair.Item2} in script {scriptName}: {scriptsCode[pair.Item1][pair.Item2 - 1]}"; // - 1 because line numbers start from 1
+                }));
                 if (exTypesDict is not null)
                 {
                     string exTypesStr = string.Join(",\n", exTypesDict.Select(x => $"{x.Key}{((x.Value > 1) ? " (x" + x.Value + ")" : string.Empty)}"));
@@ -2577,8 +2606,7 @@
 
         private async Task RunScriptNow(string path)
         {
-            string scriptText = $"#line 1 \"{path}\"\n" + File.ReadAllText(path);
-            Debug.WriteLine(path);
+            string scriptText = ScriptUtil.ProcessScriptText($"#line 1 \"{path}\"\n" + File.ReadAllText(path), path);
 
             Dispatcher.Invoke(() => CommandBox.Text = "Running " + Path.GetFileName(path) + " ...");
             try
@@ -2615,7 +2643,7 @@
                 string excString = string.Empty;
 
                 if (!isScriptException)
-                    excString = ProcessException(in exc, in scriptText);
+                    excString = ProcessException(in exc);
 
                 await StopProgressBarUpdater();
 
@@ -2998,7 +3026,7 @@
                 webClient.DownloadProgressChanged += new DownloadProgressChangedEventHandler((sender, e) =>
                 {
                     if (!end)
                         downloaded = (e.BytesReceived / bytesToMB).ToString("F2", CultureInfo.InvariantCulture);
                 });
                 webClient.DownloadFileCompleted += new AsyncCompletedEventHandler((sender, e) =>
                 {