Tests stop sharing WPF threads, Postgres roles and runner CPU

.github/workflows/build.yml

@@ -2638,7 +2638,8 @@ jobs:
               - 'Darling/Darling.Tests/McpArgumentTypeRows.cs'
               - 'Darling/Darling.Tests/StatementScrubCanary.cs'
               - 'Darling/Darling.Tests/GuardStageScanner.cs'
-              - 'Darling/Darling.Tests/WpfStaGate.cs'
+              - 'Darling/Darling.Tests/StaTestThread.cs'
+              - 'Darling/Darling.Tests/TimingTestScanner.cs'
               - 'Darling/Darling.Tests/WpfExitSwitchTests.cs'
       # How much of the Lite suite THIS leg runs, decided from the filter answers alone (no build needed):
       #   full  - a Lite, Lite.Tests, core or root path changed, or a Darling.Tests file that Lite.Tests

Darling/Darling.Tests/AvailabilityGroupsTabRefreshTests.cs

@@ -35,7 +35,7 @@ public void Render_SameRowsAcrossTwoCalls_KeepsTheSameCardInstances()
         /* The pin the ruling asks for: two refreshes over identical rows must not hand the ItemsControl a new
            object per card. Before the fix, Render assigns a brand new List<AgTopologyCard> (brand new instances)
            every call, so this fails on the pre-#4238 code — proven once, below. */
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var tab = new AvailabilityGroupsTab();
 
@@ -56,7 +56,7 @@ public void Render_SameRowsAcrossTwoCalls_KeepsTheSameCardInstances()
     [Fact]
     public void Render_ChangedValue_UpdatesInPlace_SameInstanceNewValue()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var tab = new AvailabilityGroupsTab();
 
@@ -80,7 +80,7 @@ public void Render_ChangedValue_UpdatesInPlace_SameInstanceNewValue()
     [Fact]
     public void Render_AddedOrRemovedAg_AddsOrRemovesExactlyOneCard()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var tab = new AvailabilityGroupsTab();
 
@@ -129,7 +129,7 @@ public void Render_UnchangedRows_ReplacesNoCardReplicaOrDatabaseInstances()
            reconcile every card, replica and database IN PLACE and never rebuild any of them. A regression that
            tears down and rebuilds rows -- or an O(n^2) loop that amounts to the same thing -- shows up here as a
            nonzero replaced count, independent of how loaded the runner is. */
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var tab = new AvailabilityGroupsTab();
             var topology = BuildTopology(agCount: 42, replicasPerAg: 2, dbRowsPerAg: 9, extraDbRowsOnFirst: 20);
@@ -253,23 +253,4 @@ private static AgTopologyDatabaseRow Database(int serverId, string serverName, s
             RedoRateKbPerSec = 0,
         };
 
-    /// <summary>WPF objects require STA; same shape as RawWindowFloorViewerPortTests / Lite.Tests' MainWindowAccessKeyTests.</summary>
-    private static void OnStaThread(Action body)
-    {
-        Exception? error = null;
-        using var staGate = WpfStaGate.Enter();
-        var thread = new Thread(() =>
-        {
-            try { body(); }
-            catch (Exception ex) { error = ex; }
-        });
-        thread.SetApartmentState(ApartmentState.STA);
-        thread.Start();
-        thread.Join();
-
-        if (error is not null)
-        {
-            throw error;
-        }
-    }
 }

Darling/Darling.Tests/BoundedCompressionDdlTests.cs

@@ -23,6 +23,7 @@ namespace Darling.Tests;
 /// failed settings read.
 /// </summary>
 /* #1776 own-store: each live fact mints its own scratch database through ScratchPostgres. */
+[Collection("timing")]
 public sealed class BoundedCompressionDdlTests
 {
     private static string Storage() =>

Darling/Darling.Tests/ColumnFilterPersistenceTests.cs

@@ -509,24 +509,6 @@ private sealed class LoginRow
         public string? Detail { get; set; }
     }
 
-    private static T OnStaThread<T>(Func<T> body)
-    {
-        T result = default!;
-        Exception? error = null;
-        using var staGate = WpfStaGate.Enter();
-        var thread = new Thread(() =>
-        {
-            try { result = body(); }
-            catch (Exception ex) { error = ex; }
-        });
-        thread.SetApartmentState(ApartmentState.STA);
-        thread.Start();
-        thread.Join();
-        if (error is not null)
-            throw error;
-        return result;
-    }
-
     private static DataGrid NewGrid(string? name, string? server)
     {
         var grid = new DataGrid { AutoGenerateColumns = false };
@@ -555,7 +537,7 @@ private static void Untick(IDataGridFilterManager manager, string column, string
     [Fact]
     public void A_text_match_on_a_query_text_column_lasts_the_session_but_is_not_stored()
     {
-        var kept = OnStaThread(() =>
+        var kept = StaTestThread.Run(() =>
         {
             var store = NewStore();
             ColumnFilterStore.Current = store;
@@ -591,7 +573,7 @@ public void A_text_match_on_a_query_text_column_lasts_the_session_but_is_not_sto
     [Fact]
     public void A_filter_survives_a_refresh_and_a_value_that_first_appears_later_still_shows()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var grid = NewGrid("G", null);
             var manager = new DataGridFilterManager<LoginRow>(grid);
@@ -610,7 +592,7 @@ public void A_filter_survives_a_refresh_and_a_value_that_first_appears_later_sti
     [Fact]
     public void The_value_list_comes_from_the_unfiltered_rows_not_the_ones_shown()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var grid = NewGrid("G", null);
             var manager = new DataGridFilterManager<LoginRow>(grid);
@@ -626,7 +608,7 @@ public void The_value_list_comes_from_the_unfiltered_rows_not_the_ones_shown()
     [Fact]
     public void Number_query_text_and_prose_columns_and_columns_the_row_lacks_get_no_list()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var grid = NewGrid("G", null);
             var manager = new DataGridFilterManager<LoginRow>(grid);
@@ -645,7 +627,7 @@ public void Number_query_text_and_prose_columns_and_columns_the_row_lacks_get_no
     [Fact]
     public void A_text_column_that_sorts_by_another_member_gets_no_list()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var grid = NewGrid("G", null);
             ((DataGridTextColumn)grid.Columns[0]).SortMemberPath = "SessionId";
@@ -660,7 +642,7 @@ public void A_text_column_that_sorts_by_another_member_gets_no_list()
     [Fact]
     public void A_column_with_a_value_over_256_characters_gets_no_list()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var grid = NewGrid("G", null);
             var manager = new DataGridFilterManager<LoginRow>(grid);
@@ -674,7 +656,7 @@ public void A_column_with_a_value_over_256_characters_gets_no_list()
     [Fact]
     public void A_filter_set_in_one_session_is_loaded_by_the_next_on_its_first_refresh()
     {
-        var shown = OnStaThread(() =>
+        var shown = StaTestThread.Run(() =>
         {
             var store = NewStore();
             ColumnFilterStore.Current = store;
@@ -700,7 +682,7 @@ public void A_filter_set_in_one_session_is_loaded_by_the_next_on_its_first_refre
     [Fact]
     public void A_cross_server_list_under_the_all_servers_scope_keeps_its_filters_across_a_restart()
     {
-        var shown = OnStaThread(() =>
+        var shown = StaTestThread.Run(() =>
         {
             var store = NewStore();
             ColumnFilterStore.Current = store;
@@ -723,7 +705,7 @@ public void A_cross_server_list_under_the_all_servers_scope_keeps_its_filters_ac
     [Fact]
     public void Another_servers_filters_do_not_apply_and_a_grid_without_a_name_or_scope_is_not_stored()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var store = NewStore();
             ColumnFilterStore.Current = store;
@@ -757,7 +739,7 @@ public void Another_servers_filters_do_not_apply_and_a_grid_without_a_name_or_sc
     [Fact]
     public void A_stored_filter_on_a_column_the_grid_no_longer_has_is_ignored()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var store = NewStore();
             store.Save("srv-a", "G", new[] { Hide("RetiredColumn", "x"), Hide("LoginName", "job_svc") });
@@ -776,7 +758,7 @@ public void A_stored_filter_on_a_column_the_grid_no_longer_has_is_ignored()
     [Fact]
     public void Clear_all_filters_clears_the_grid_and_the_stored_copy_but_a_server_switch_does_not()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var store = NewStore();
             ColumnFilterStore.Current = store;
@@ -806,7 +788,7 @@ public void Clear_all_filters_clears_the_grid_and_the_stored_copy_but_a_server_s
     [Fact]
     public void A_server_switch_loads_the_new_servers_own_filters()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var store = NewStore();
             store.Save("srv-b", "G", new[] { Hide("LoginName", "sa") });
@@ -828,7 +810,7 @@ public void A_server_switch_loads_the_new_servers_own_filters()
     [Fact]
     public void A_store_that_fails_never_blocks_the_grid()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             File.WriteAllText(FilePath, "garbage");
             ColumnFilterStore.Current = NewStore();

Darling/Darling.Tests/ColumnFilterPopupTests.cs

@@ -26,24 +26,6 @@ namespace Darling.Tests;
 /// </summary>
 public sealed class ColumnFilterPopupTests
 {
-    private static T OnStaThread<T>(Func<T> body)
-    {
-        T result = default!;
-        Exception? error = null;
-        using var staGate = WpfStaGate.Enter();
-        var thread = new Thread(() =>
-        {
-            try { result = body(); }
-            catch (Exception ex) { error = ex; }
-        });
-        thread.SetApartmentState(ApartmentState.STA);
-        thread.Start();
-        thread.Join();
-        if (error is not null)
-            throw error;
-        return result;
-    }
-
     private static T Find<T>(DependencyObject root, Func<T, bool> where) where T : DependencyObject
     {
         foreach (var child in LogicalTreeHelper.GetChildren(root).OfType<DependencyObject>())
@@ -65,7 +47,7 @@ private static Button ButtonNamed(ColumnFilterPopup popup, string content) =>
     [Fact]
     public void The_list_section_shows_only_for_a_column_with_a_catalog()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var popup = new ColumnFilterPopup();
             var panel = Find<StackPanel>(popup, p => p.Name == "ValueListPanel");
@@ -84,7 +66,7 @@ public void The_list_section_shows_only_for_a_column_with_a_catalog()
     [Fact]
     public void The_search_box_narrows_the_list_and_Select_All_covers_what_it_shows()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var popup = new ColumnFilterPopup();
             popup.Initialize("LoginName", null, Catalog("sa", "app", "job_svc", null));
@@ -113,7 +95,7 @@ public void The_search_box_narrows_the_list_and_Select_All_covers_what_it_shows(
     [Fact]
     public void Nothing_ticked_shows_the_note_and_the_cap_note_shows_for_a_long_list()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var popup = new ColumnFilterPopup();
             popup.Initialize("LoginName", null, Catalog("a", "b"));
@@ -134,7 +116,7 @@ public void Nothing_ticked_shows_the_note_and_the_cap_note_shows_for_a_long_list
     [Fact]
     public void An_existing_value_filter_comes_back_as_the_ticks_and_the_text_match_beside_it()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var existing = new ColumnFilterState { ColumnName = "LoginName", ValueMode = ColumnValueMode.Hide, Operator = FilterOperator.StartsWith, Value = "s" };
             existing.Values.Add("job_svc");
@@ -158,7 +140,7 @@ public void An_existing_value_filter_comes_back_as_the_ticks_and_the_text_match_
     [Fact]
     public void A_column_without_a_list_keeps_a_stored_value_filter_when_the_text_match_is_applied()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var existing = new ColumnFilterState { ColumnName = "LoginName", ValueMode = ColumnValueMode.ShowOnly };
             existing.Values.Add("sa");
@@ -178,7 +160,7 @@ public void A_column_without_a_list_keeps_a_stored_value_filter_when_the_text_ma
     [Fact]
     public void A_text_only_apply_keeps_the_stored_value_part_even_when_todays_rows_have_drifted_from_it()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             /* Scenario A: stored ShowOnly {sa}, but the rows now hold only sa. Re-deriving the mode would find nothing
                unticked, give None, and drop the filter. */
@@ -214,7 +196,7 @@ public void A_text_only_apply_keeps_the_stored_value_part_even_when_todays_rows_
     [Fact]
     public void Select_All_unticked_shows_the_no_values_note_at_once()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var popup = new ColumnFilterPopup();
             popup.Initialize("LoginName", null, Catalog("a", "b"));
@@ -234,7 +216,7 @@ public void Select_All_unticked_shows_the_no_values_note_at_once()
     [Fact]
     public void A_stored_value_part_on_a_column_with_no_list_shows_read_only_with_a_way_to_clear_it()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var existing = new ColumnFilterState { ColumnName = "LoginName", ValueMode = ColumnValueMode.Hide };
             existing.Values.Add("a");
@@ -276,7 +258,7 @@ public void A_stored_value_part_on_a_column_with_no_list_shows_read_only_with_a_
     [Fact]
     public void Clear_all_filters_shows_only_when_the_grid_has_a_filter_and_raises_its_event()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var popup = new ColumnFilterPopup();
             var button = ButtonNamed(popup, "Clear all filters");
@@ -297,7 +279,7 @@ public void Clear_all_filters_shows_only_when_the_grid_has_a_filter_and_raises_i
     [Fact]
     public void Clear_applies_an_empty_filter_including_the_value_part()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var existing = new ColumnFilterState { ColumnName = "LoginName", ValueMode = ColumnValueMode.Hide };
             existing.Values.Add("a");
@@ -316,7 +298,7 @@ public void Clear_applies_an_empty_filter_including_the_value_part()
     [Fact]
     public void Esc_closes_the_popup_from_anywhere_in_it_and_the_list_is_virtualised_and_tab_stops_once()
     {
-        OnStaThread(() =>
+        StaTestThread.Run(() =>
         {
             var popup = new ColumnFilterPopup();
             popup.Initialize("LoginName", null, Catalog("a", "b"));