Point the crash report at the minidump the simulator left

The simulator writes crash_*.dmp relative to its working directory, and
crashpad under crashdumps; the newest one from this run is named, with an
offer to open its folder.

StarterNG.Tests/StartSimulationTests.cs

@@ -68,6 +68,23 @@ public class StartSimulationTests
         Assert.False(launcher.CapturedErrors);
     }
 
+    [Fact]
+    public void Minidumps_of_this_run_are_found_in_the_installation_and_under_crashpad()
+    {
+        var (start, _, installation) = Rig(files => files
+            .WithExecutable(Build)
+            .WithFile(TestInstallation.At("crash_2026-10-04_13-03-12.dmp"), "MDMP")
+            .WithFile(TestInstallation.At("crashdumps", "reports", "1a2b.dmp"), "MDMP"));
+        installation.Files.LastWriteTimeUtc = new DateTime(2026, 10, 4, 11, 3, 12, DateTimeKind.Utc);
+
+        var thisRun = start.CrashDumpsSince(new DateTime(2026, 10, 4, 11, 3, 0, DateTimeKind.Utc), Build);
+        var later = start.CrashDumpsSince(new DateTime(2026, 10, 4, 12, 0, 0, DateTimeKind.Utc), Build);
+
+        Assert.Equal(2, thisRun.Count);
+        Assert.Contains(thisRun, dump => dump.EndsWith("crash_2026-10-04_13-03-12.dmp"));
+        Assert.Empty(later);
+    }
+
     [Fact]
     public void The_end_of_the_simulator_log_is_read_for_a_silent_crash()
     {

StarterNG/Application/StartSimulation.cs

@@ -63,6 +63,41 @@ public sealed class StartSimulation
         _log = log;
     }
 
+    /// <summary>
+    /// Minidumps written since the simulator was started, newest first. The
+    /// simulator names them crash_*.dmp relative to its working directory - the
+    /// installation - and crashpad, where it is set up, keeps its own under
+    /// crashdumps; the folder of the binary is looked at too, for a simulator that
+    /// was once run from there.
+    /// </summary>
+    public IReadOnlyList<string> CrashDumpsSince(DateTime startedUtc, string executable)
+    {
+        var dumps = new List<string>();
+        try
+        {
+            foreach (string directory in new[] { _paths.Root, Path.GetDirectoryName(executable) ?? _paths.Root }
+                         .Distinct(StringComparer.OrdinalIgnoreCase)
+                         .Where(_files.DirectoryExists))
+                dumps.AddRange(_files.GetFiles(directory, "*.dmp"));
+
+            string crashpad = _paths.FromRoot("crashdumps");
+            if (_files.DirectoryExists(crashpad))
+                dumps.AddRange(_files.GetFilesRecursive(crashpad, "*.dmp"));
+
+            // A little slack: the start is taken just after the launch, not before it.
+            var since = startedUtc - TimeSpan.FromSeconds(5);
+            return dumps.Distinct(StringComparer.OrdinalIgnoreCase)
+                        .Where(dump => _files.GetLastWriteTimeUtc(dump) >= since)
+                        .OrderByDescending(_files.GetLastWriteTimeUtc)
+                        .ToList();
+        }
+        catch (Exception ex)
+        {
+            _log.Log("looking for crash dumps", ex);
+            return Array.Empty<string>();
+        }
+    }
+
     /// <summary>The end of the simulator's own log, for when it died without a word on its error stream.</summary>
     public IReadOnlyList<string> SimulatorLogTail(int count)
     {

StarterNG/MainWindow.axaml.cs

@@ -522,14 +522,14 @@ public partial class MainWindow : Window
         GC.Collect();
         GC.WaitForPendingFinalizers();
 
-        WatchSimulator(result.Process);
+        WatchSimulator(result.Process, result.ExecutablePath);
     }
 
     /// <summary>
     /// Brings the starter back when the simulator exits. Adopts an already
     /// running simulator when we did not start it ourselves.
     /// </summary>
-    private void WatchSimulator(IProcessHandle? simulator)
+    private void WatchSimulator(IProcessHandle? simulator, string executable)
     {
         var started = DateTime.UtcNow;
         simulator ??= AppServices.Current.Processes.FindRunning(
@@ -544,7 +544,7 @@ public partial class MainWindow : Window
         _ = simulator.WaitForExitAsync().ContinueWith(_ => Dispatcher.UIThread.Post(() =>
         {
             RestoreFromSimulator();
-            ReportIfCrashed(simulator, DateTime.UtcNow - started);
+            ReportIfCrashed(simulator, executable, started);
         }), TaskScheduler.Default);
     }
 
@@ -552,13 +552,15 @@ public partial class MainWindow : Window
     /// Says why the simulator is gone when it did not end the way a session does:
     /// an error code, or a close so soon after the start that nobody played - a
     /// window that only flashed. Its own words come from the error stream, or from
-    /// its log when that stayed silent.
+    /// its log when that stayed silent, and a minidump it left is pointed at.
     /// </summary>
-    private async void ReportIfCrashed(IProcessHandle simulator, TimeSpan runTime)
+    private async void ReportIfCrashed(IProcessHandle simulator, string executable, DateTime startedUtc)
     {
         if (simulator.ExitCode is not { } code)
             return;
 
+        var runTime = DateTime.UtcNow - startedUtc;
+
         var exit = new SimulatorExit(code, runTime, simulator.ErrorTail);
         if (!exit.Failed)
             return;
@@ -579,8 +581,16 @@ public partial class MainWindow : Window
         }
         message.AppendLine().Append(App.Loc["SimExitSeeLog"]);
 
+        string? dump = AppServices.Current.StartSimulation.CrashDumpsSince(startedUtc, executable).FirstOrDefault();
+        if (dump is not null)
+            message.AppendLine().AppendLine().AppendLine(string.Format(App.Loc["SimExitDump"], dump))
+                   .Append(App.Loc["SimExitOpenDump"]);
+
         Diagnostics.Log(message.ToString().Replace(Environment.NewLine, " | "));
-        await MessageBox.Show(this, message.ToString(), App.Loc["SimExitTitle"], MessageBoxButtons.Ok);
+        bool open = await MessageBox.Show(this, message.ToString(), App.Loc["SimExitTitle"],
+                                          dump is null ? MessageBoxButtons.Ok : MessageBoxButtons.YesNo);
+        if (open && dump is not null && Path.GetDirectoryName(Path.GetFullPath(dump)) is { } folder)
+            AppServices.Current.Processes.OpenInShell(folder);
     }
 
     private async void CheckExternalSettings()

StarterNG/startercfg/lang/cz.xml

@@ -258,6 +258,8 @@
     <String key="SimExitQuick">Ukončil se {0:0.0} s po spuštění.</String>
     <String key="SimExitMessages">Poslední zprávy:</String>
     <String key="SimExitSeeLog">Celý průběh je v souboru log.txt ve složce simulátoru.</String>
+    <String key="SimExitDump">Simulátor uložil výpis paměti: {0}</String>
+    <String key="SimExitOpenDump">Otevřít složku s výpisem? Přiložte jej k hlášení chyby.</String>
     <String key="TabInfo">Informace</String>
     <String key="SettingsFileChangedTitle">Nastavení</String>
     <String key="SettingsFileChanged">Soubor eu07.ini byl změněn mimo starter. Načíst jej znovu?</String>

StarterNG/startercfg/lang/en.xml

@@ -258,6 +258,8 @@
     <String key="SimExitQuick">It closed {0:0.0} s after starting.</String>
     <String key="SimExitMessages">Last messages:</String>
     <String key="SimExitSeeLog">The full run is in log.txt in the simulator folder.</String>
+    <String key="SimExitDump">The simulator saved a memory dump: {0}</String>
+    <String key="SimExitOpenDump">Open the folder with the dump? Attach it to the bug report.</String>
     <String key="TabInfo">Info</String>
     <String key="SettingsFileChangedTitle">Settings</String>
     <String key="SettingsFileChanged">eu07.ini was changed outside the starter. Reload it?</String>

StarterNG/startercfg/lang/hu.xml

@@ -258,6 +258,8 @@
     <String key="SimExitQuick">{0:0.0} másodperccel az indítás után bezárult.</String>
     <String key="SimExitMessages">Utolsó üzenetek:</String>
     <String key="SimExitSeeLog">A teljes futás a szimulátor mappájában lévő log.txt fájlban található.</String>
+    <String key="SimExitDump">A szimulátor memóriaképet mentett: {0}</String>
+    <String key="SimExitOpenDump">Megnyitod a memóriaképet tartalmazó mappát? Csatold a hibajelentéshez.</String>
     <String key="TabInfo">Információ</String>
     <String key="SettingsFileChangedTitle">Beállítások</String>
     <String key="SettingsFileChanged">Az eu07.ini fájl a starteren kívül módosult. Újratölti?</String>

StarterNG/startercfg/lang/pl.xml

@@ -258,6 +258,8 @@
     <String key="SimExitQuick">Zamknął się {0:0.0} s po uruchomieniu.</String>
     <String key="SimExitMessages">Ostatnie komunikaty:</String>
     <String key="SimExitSeeLog">Pełny przebieg jest w pliku log.txt w katalogu symulatora.</String>
+    <String key="SimExitDump">Symulator zapisał zrzut pamięci: {0}</String>
+    <String key="SimExitOpenDump">Otworzyć folder ze zrzutem? Dołącz go do zgłoszenia błędu.</String>
     <String key="TabInfo">Informacje</String>
     <String key="SettingsFileChangedTitle">Ustawienia</String>
     <String key="SettingsFileChanged">Plik eu07.ini został zmieniony poza starterem. Wczytać ponownie?</String>

StarterNG/startercfg/lang/ru.xml

@@ -258,6 +258,8 @@
     <String key="SimExitQuick">Он закрылся через {0:0.0} с после запуска.</String>
     <String key="SimExitMessages">Последние сообщения:</String>
     <String key="SimExitSeeLog">Полный журнал находится в файле log.txt в папке симулятора.</String>
+    <String key="SimExitDump">Симулятор сохранил дамп памяти: {0}</String>
+    <String key="SimExitOpenDump">Открыть папку с дампом? Приложите его к сообщению об ошибке.</String>
     <String key="TabInfo">Информация</String>
     <String key="SettingsFileChangedTitle">Настройки</String>
     <String key="SettingsFileChanged">Файл eu07.ini изменён вне стартера. Загрузить заново?</String>