diff --git a/src/ILICheck.Web/ClientApp/src/logHierarchy.test.js b/src/ILICheck.Web/ClientApp/src/logHierarchy.test.js
new file mode 100644
index 0000000..5ea2f66
--- /dev/null
+++ b/src/ILICheck.Web/ClientApp/src/logHierarchy.test.js
@@ -0,0 +1,143 @@
+import { describe, expect, test } from "@jest/globals";
+import { createLogHierarchy } from "./logHierarchy";
+
+describe("transform log data to hierarchy", () => {
+  test("constraint pass", () => {
+    const data = [
+      {
+        tid: "o1",
+        message: "validate set constraint ModelA.TopicA.ClassA.ConstraintName...",
+        type: "Info",
+      },
+    ];
+
+    const expected = [
+      {
+        message: "ModelA",
+        type: "Info",
+        values: [
+          {
+            message: "TopicA.ClassA",
+            type: "Info",
+            values: [{ message: "Set Constraint ConstraintName", type: "Info" }],
+          },
+        ],
+      },
+    ];
+
+    const hierarchy = createLogHierarchy(data);
+
+    expect(hierarchy).toStrictEqual(expected);
+  });
+
+  test("constraint fail", () => {
+    const data = [
+      {
+        tid: "o1",
+        message: "validate existence constraint ModelA.TopicA.ClassA.ConstraintName...",
+        type: "Info",
+      },
+      {
+        tid: "o2",
+        message: "Some other message",
+        type: "Info",
+      },
+      {
+        tid: "o3",
+        message:
+          "Existence constraint ModelA.TopicA.ClassA.ConstraintName is violated! The value of the attribute Test of t1 was not found in the condition class.",
+        type: "Error",
+      },
+    ];
+
+    const expected = [
+      {
+        message: "ModelA",
+        type: "Error",
+        values: [
+          {
+            message: "TopicA.ClassA",
+            type: "Error",
+            values: [
+              {
+                message:
+                  "Existence constraint ConstraintName is violated! The value of the attribute Test of t1 was not found in the condition class.",
+                type: "Error",
+              },
+            ],
+          },
+        ],
+      },
+    ];
+
+    const hierarchy = createLogHierarchy(data);
+
+    expect(hierarchy).toStrictEqual(expected);
+  });
+
+  test("mixed log types", () => {
+    const data = [
+      {
+        tid: "o1",
+        message: "validate data...",
+        type: "Info",
+      },
+      {
+        tid: "o2",
+        message: "lookup model <Base> 2.3 in repository <http://models.geo.admin.ch/>",
+        type: "Info",
+      },
+      {
+        tid: "o3",
+        message: "validate mandatory constraint ModelA.TopicA.ClassA.ConstraintName...",
+        type: "Info",
+      },
+      {
+        tid: "o4",
+        message:
+          "MandatoryConstraint ModelA.TopicA.ClassA.ConstraintName of ModelA.TopicA.ClassA is not yet implemented.",
+        type: "Warning",
+      },
+      {
+        tid: "o5",
+        message: "validate mandatory constraint ModelA.TopicA.ClassA.Constraint1...",
+        type: "Info",
+      },
+      {
+        tid: "o6",
+        message: "validate mandatory constraint ModelA.TopicA.ClassA.Constraint2...",
+        type: "Info",
+      },
+      {
+        tid: "o7",
+        message: "Custom message for constraint. ModelA.TopicA.ClassA.Constraint1 (MANDATORY CONSTRAINT DEFINED(Abc);)",
+        type: "Error",
+      },
+    ];
+
+    const expected = [
+      {
+        message: "ModelA",
+        type: "Error",
+        values: [
+          {
+            message: "TopicA.ClassA",
+            type: "Error",
+            values: [
+              {
+                message: "MandatoryConstraint ConstraintName of ModelA.TopicA.ClassA is not yet implemented.",
+                type: "Warning",
+              },
+              { message: "Custom message for constraint.", type: "Error" },
+              { message: "Mandatory Constraint Constraint2", type: "Info" },
+            ],
+          },
+        ],
+      },
+    ];
+
+    const hierarchy = createLogHierarchy(data);
+
+    expect(hierarchy).toStrictEqual(expected);
+  });
+});