From 7660068512d9c59228266d38f01ea12f05d2c9fd Mon Sep 17 00:00:00 2001
From: Seun Akanni <seun.akanni@burohappold.com>
Date: Mon, 24 Aug 2026 11:04:40 +0100
Subject: [PATCH 1/2] validate: serialisation proxy pinned to the item 4 fix
 (not for merge)

---
 .github/workflows/ci.yml | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 .github/workflows/ci.yml

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 00000000..c11389da
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,19 @@
+# Sandbox validation of CI_Toolkit PR #9: forces the ci-serialisation baseline leg.
+# Pinned to the fix branch. Not for merge.
+name: CI
+on:
+  pull_request:
+    branches: [develop]
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+jobs:
+  ci-serialisation:
+    runs-on: windows-2025-vs2026
+    timeout-minutes: 90
+    steps:
+      - uses: BuroHappoldEngineeringSandbox/CI_Toolkit/.github/actions/ci-serialisation@validate/item4-integration
+        with:
+          app_id: ${{ secrets.BHOM_APP_ID }}
+          private_key: ${{ secrets.BHOM_APP_PRIVATE_KEY }}
+          base_ref: ${{ github.base_ref }}

From bc961c099f1db6796a4d618d85e68c5ac4e3820e Mon Sep 17 00:00:00 2001
From: Seun Akanni <seun.akanni@burohappold.com>
Date: Mon, 24 Aug 2026 11:04:41 +0100
Subject: [PATCH 2/2] validate: deliberate non-round-tripping type to force the
 baseline leg (not for merge)

---
 XML_oM/Item4Fixture/UnserialisableFixture.cs | 36 ++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100644 XML_oM/Item4Fixture/UnserialisableFixture.cs

diff --git a/XML_oM/Item4Fixture/UnserialisableFixture.cs b/XML_oM/Item4Fixture/UnserialisableFixture.cs
new file mode 100644
index 00000000..cf8d13c4
--- /dev/null
+++ b/XML_oM/Item4Fixture/UnserialisableFixture.cs
@@ -0,0 +1,36 @@
+/*
+ * DELIBERATE SERIALISATION FIXTURE. NOT FOR MERGE.
+ *
+ * Authored to validate CI_Toolkit PR #9 (findings-register item 4). ci-serialisation only
+ * runs its baseline leg when the branch leg reports status == 'Error', and no sandbox repo
+ * currently produces a serialisation failure, so the baseline path had never executed under
+ * the fix. This type forces one.
+ *
+ * Why it fails: Helpers.ObjectTypesToTest() selects every non-abstract IObject whose every
+ * property sits in a BH.* or System.* namespace, so System.IntPtr passes selection. The BHoM
+ * serialiser has no BSON mapping for IntPtr, so ToJson() throws, Verify records an error, the
+ * json comes back empty and ObjectToFromJson returns TestStatus.Error for this type.
+ *
+ * The failure is subject-side and exists only on this branch, so the baseline leg should not
+ * see it and the comparator should report a regression. That is the intended outcome.
+ */
+
+using System;
+using System.Collections.Generic;
+
+using BH.oM.Base;
+
+namespace BH.oM.XML.Item4Fixture
+{
+    public class UnserialisableFixture : IBHoMObject
+    {
+        // The whole fixture: IntPtr has no BSON serialiser.
+        public virtual IntPtr Handle { get; set; } = IntPtr.Zero;
+
+        public virtual Guid BHoM_Guid { get; set; } = Guid.NewGuid();
+        public virtual Dictionary<string, object> CustomData { get; set; } = new Dictionary<string, object>();
+        public virtual string Name { get; set; } = "";
+        public virtual FragmentSet Fragments { get; set; } = new FragmentSet();
+        public virtual HashSet<string> Tags { get; set; } = new HashSet<string>();
+    }
+}