test(markdown): create test for crash due to format property

example provided by @AndyOGo in
#198 (comment)

see #198

test/fixtures/format/format.schema.json

@@ -0,0 +1,19 @@
+{
+  "type": "object",
+  "title": "Properties",
+  "description": "Properties of Datepicker.",
+
+  "additionalProperties": false,
+  "properties": {
+    "format": {
+      "type": "string",
+      "title": "Format",
+      "description": "Formatting used to display the date."
+    },
+    "value": {
+      "type": "string",
+      "title": "Value",
+      "description": "Date to be displayed."
+    }
+  }
+}

test/markdownBuilder.test.js

@@ -82,6 +82,21 @@ describe('Testing Markdown Builder: title', () => {
   });
 });
 
+describe('Testing Markdown Builder: format', () => {
+  let results;
+
+  before(async () => {
+    const schemas = await loadschemas('format');
+    const builder = build({ header: false });
+    results = builder(schemas);
+  });
+
+  it('Format Schema looks OK', () => {
+    assertMarkdown(results.properties)
+      .fuzzy`defined in: [Meta](meta-definitions-meta-properties-title.md "https://ns.adobe.com/helix/pipeline/meta#/definitions/meta/properties/title")`;
+  });
+});
+
 describe('Testing Markdown Builder: enums', () => {
   let results;