Updating Asciidoc test to verify valid output

Author: nbiastaunton

core/src/test/java/org/openapitools/openapidiff/core/AsciidocRenderTest.java

@@ -40,4 +40,32 @@ public void renderDoesNotFailWhenHTTPStatusCodeIsRange() {
     render.render(diff, outputStreamWriter);
     assertThat(outputStream.toString()).isNotBlank();
   }
+
+  @Test
+  public void validateAsciiDocChangeFile() {
+    AsciidocRender render = new AsciidocRender();
+    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+    OutputStreamWriter outputStreamWriter = new OutputStreamWriter(outputStream);
+    ChangedOpenApi diff =
+            OpenApiCompare.fromLocations("missing_property_1.yaml", "missing_property_2.yaml");
+    render.render(diff, outputStreamWriter);
+    assertThat(outputStream.toString())
+            .isEqualTo(
+                    "= TITLE (v 1.0.0)\n" +
+                            ":reproducible:\n" +
+                            ":sectlinks:\n" +
+                            ":toc:\n" +
+                            "\n" +
+                            "== What's Changed\n" +
+                            "=== GET   /\n" +
+                            "* Return Type:\n" +
+                            "** Changed default \n" +
+                            "** Media types:\n" +
+                            "*** Changed application/json\n" +
+                            "*** Schema:\n" +
+                            "Backward compatible\n" +
+                            "\n" +
+                            "\n" +
+                            "NOTE: API changes are backward compatible");
+  }
 }