From 59e094ada307c03bb61658993e1aa4c1ae9af4d8 Mon Sep 17 00:00:00 2001
From: Joseph Doherty <dohejw01@gmail.com>
Date: Wed, 17 Jun 2026 16:08:37 -0400
Subject: [PATCH] =?UTF-8?q?test(playwright):=20DebugViewTree=20=E2=80=94?=
 =?UTF-8?q?=20tolerate=20empty=20alarm=20forest=20(TreeView=20renders=20Em?=
 =?UTF-8?q?ptyContent,=20not=20role=3Dtree,=20when=20no=20alarms)?=
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---
 .../Deployment/DebugViewTreeTests.cs          | 31 ++++++++++++-------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/tests/ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests/Deployment/DebugViewTreeTests.cs b/tests/ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests/Deployment/DebugViewTreeTests.cs
index 13c5c134..0fd056f8 100644
--- a/tests/ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests/Deployment/DebugViewTreeTests.cs
+++ b/tests/ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests/Deployment/DebugViewTreeTests.cs
@@ -37,14 +37,14 @@ namespace ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests.Deployment;
 /// </para>
 ///
 /// <para>
-/// <b>Why the tree assertion is robust regardless of seeded alarms</b> — the
-/// <see cref="TreeView{T}"/> always renders its <c>&lt;ul role="tree"&gt;</c> root
-/// (with an <c>EmptyContent</c> "No alarms." / "No attributes." slot when the
-/// forest is empty), so asserting a <c>[role="tree"]</c> inside the active pane
-/// holds whether or not the fixture instance happens to carry a configured alarm
-/// or composition members. The test therefore does NOT depend on heavy alarm
-/// seeding: it proves the Alarms tab switches the visible pane and that pane hosts
-/// a tree, which is the structural contract of the tabs+trees rework.
+/// <b>Why the alarms-tab assertion is tolerant</b> — the
+/// <see cref="TreeView{T}"/> renders its <c>&lt;ul role="tree"&gt;</c> root ONLY
+/// when the forest is non-empty; when empty it renders the <c>EmptyContent</c>
+/// slot ("No alarms.") with no <c>[role="tree"]</c> element. The seeded
+/// <see cref="DeploymentFixture"/> instance has no configured alarms, so the
+/// alarms pane shows the empty hint. The Attributes pane always has data (one
+/// attribute is seeded), so its <c>[role="tree"]</c> assertion remains strict.
+/// The populated alarm tree is covered by bUnit tests (DebugViewAlarmTableTests).
 /// </para>
 /// </summary>
 [Collection("Playwright")]
@@ -116,9 +116,18 @@ public class DebugViewTreeTests : IClassFixture<DeploymentFixture>
             await Assertions.Expect(alarmTab).ToHaveAttributeAsync("aria-selected", "true");
             await Assertions.Expect(alarmPane).ToBeVisibleAsync(new() { Timeout = 10_000 });
             await Assertions.Expect(attrPane).ToBeHiddenAsync();
-            // The TreeView always renders its <ul role="tree"> root (EmptyContent slot when
-            // the forest is empty), so this holds whether or not the instance carries alarms.
-            await Assertions.Expect(alarmPane.Locator("[role='tree']")).ToHaveCountAsync(1);
+            // TreeView renders <ul role="tree"> ONLY when the forest is non-empty; when empty it
+            // renders the EmptyContent slot ("No alarms.") instead. The seeded DeploymentFixture
+            // instance has no configured alarms, so the alarms forest is empty and the pane shows
+            // the empty hint rather than a tree. The populated alarm tree is covered by bUnit
+            // tests (DebugViewAlarmTableTests). Here we prove the tab switch works and the pane
+            // renders something valid — either a tree (if alarms exist) or the empty hint.
+            var alarmTreeCount = await alarmPane.Locator("[role='tree']").CountAsync();
+            if (alarmTreeCount == 0)
+            {
+                // No alarms configured on the seeded instance → TreeView shows EmptyContent.
+                await Assertions.Expect(alarmPane).ToContainTextAsync("No alarms.");
+            }
 
             // Disconnect tears the card down and re-enables the selectors.
             await page.Locator("button.btn-outline-danger.btn-sm:has-text('Disconnect')").ClickAsync();