Updated test cases documentation

docs/test_cases/t20026.md

@@ -47,3 +47,63 @@ int tmain()
 ```
 ## Generated UML diagrams
 ![t20026_sequence](./t20026_sequence.svg "Virtual method call sequence diagram test case")
+## Generated JSON models
+```json
+{
+  "diagram_type": "sequence",
+  "name": "t20026_sequence",
+  "participants": [
+    {
+      "id": "2268697350307997040",
+      "name": "clanguml::t20026::tmain()",
+      "source_location": {
+        "file": "../../tests/t20026/t20026.cc",
+        "line": 16
+      },
+      "type": "function"
+    },
+    {
+      "id": "1962121823853291899",
+      "name": "clanguml::t20026::A",
+      "source_location": {
+        "file": "../../tests/t20026/t20026.cc",
+        "line": 4
+      },
+      "type": "class"
+    }
+  ],
+  "sequences": [
+    {
+      "messages": [
+        {
+          "from": {
+            "activity_id": "2268697350307997040",
+            "activity_name": "clanguml::t20026::tmain()",
+            "participant_id": "2268697350307997040",
+            "participant_name": "clanguml::t20026::tmain()"
+          },
+          "name": "a()",
+          "return_type": "void",
+          "scope": "normal",
+          "source_location": {
+            "file": "../../tests/t20026/t20026.cc",
+            "line": 20
+          },
+          "to": {
+            "activity_id": "600590770418147864",
+            "activity_name": "clanguml::t20026::A::a()",
+            "participant_id": "1962121823853291899",
+            "participant_name": "clanguml::t20026::A"
+          },
+          "type": "message"
+        }
+      ],
+      "start_from": {
+        "id": 2268697350307997040,
+        "location": "clanguml::t20026::tmain()"
+      }
+    }
+  ],
+  "using_namespace": "clanguml::t20026"
+}
+```