diff --git a/src/diagrams/c4/parser/c4PersonExt.spec.js b/src/diagrams/c4/parser/c4PersonExt.spec.js
new file mode 100644
index 000000000..71faabdc3
--- /dev/null
+++ b/src/diagrams/c4/parser/c4PersonExt.spec.js
@@ -0,0 +1,44 @@
+import c4Db from '../c4Db';
+import c4 from './c4Diagram.jison';
+import { setConfig } from '../../../config';
+
+setConfig({
+  securityLevel: 'strict',
+});
+
+describe('parsing a C4 diagram', function () {
+  beforeEach(function () {
+    c4.parser.yy = c4Db;
+    c4.parser.yy.clear();
+  });
+
+  it('should parse a C4 diagram with one Person_Ext correctly', function () {
+    c4.parser.parse(`C4Context
+title System Context diagram for Internet Banking System
+Person_Ext(customerA, "Banking Customer A", "A customer of the bank, with personal bank accounts.")`);
+
+    const yy = c4.parser.yy;
+
+    const shapes = yy.getC4ShapeArray();
+    expect(shapes.length).toBe(1);
+    const onlyShape = shapes[0];
+
+    expect(onlyShape).toEqual({
+      alias: 'customerA',
+      descr: {
+        text: 'A customer of the bank, with personal bank accounts.',
+      },
+      label: {
+        text: 'Banking Customer A',
+      },
+      link: undefined,
+      sprite: undefined,
+      tags: undefined,
+      parentBoundary: 'global',
+      typeC4Shape: {
+        text: 'external_person',
+      },
+      wrap: false,
+    });
+  });
+});