Add a failing test

server/fixtures/includes-vars-erroneous-include-result.mdx

@@ -0,0 +1,12 @@
+## Installation
+
+Here is a test for including variables in an MDX file.
+
+Here are instructions for installing version 10:
+
+```code
+$ curl -OL https://example.com/downloads/mysoftware-v10.tar
+$ tar -xvf mysoftware-v10.tar
+```
+
+We no longer support version .

server/fixtures/includes-vars-erroneous-include.mdx

@@ -0,0 +1,5 @@
+## Installation
+
+Here is a test for including variables in an MDX file.
+
+(!install-version.mdx version="10" unsupport="9" !)

uvu-tests/remark-includes.test.ts

@@ -483,6 +483,25 @@ Suite("Resolves template variables in includes", () => {
   assert.equal(result, expected);
 });
 
+Suite("Removes unresolved template variables", () => {
+  const value = readFileSync(
+    resolve("server/fixtures/includes-vars-erroneous-include.mdx"),
+    "utf-8"
+  );
+
+  const expected = readFileSync(
+    resolve("server/fixtures/includes-vars-erroneous-include-result.mdx"),
+    "utf-8"
+  );
+
+  const result = transformer({
+    value,
+    path: "/content/4.0/docs/pages/filename.mdx",
+  }).toString();
+
+  assert.equal(result, expected);
+});
+
 Suite(
   "Resolves relative links in partials based on the path of the partial",
   () => {