ci: add frontmatter title style lint check

examples/sandbox/spawn_subprocess.md

@@ -1,5 +1,5 @@
 ---
-title: "Spawn a subprocess, and get buffered output"
+title: "Spawn a subprocess and get buffered output"
 description: "Learn how to spawn a subprocess, and get buffered output in a sandbox."
 url: /examples/sandbox_spawn_subprocess/
 layout: sandbox-example.tsx

frontmatter_test.ts

@@ -0,0 +1,46 @@
+import { walk } from "@std/fs";
+import { extract } from "@std/front-matter/yaml";
+import { assert, assertEquals } from "@std/assert";
+
+const DIRS_TO_CHECK = ["./runtime", "./deploy", "./examples"];
+
+Deno.test("Frontmatter titles must not contain backticks", async (t) => {
+  for (const dir of DIRS_TO_CHECK) {
+    for await (const entry of walk(dir, { exts: [".md", ".mdx"] })) {
+      const content = await Deno.readTextFile(entry.path);
+      if (!content.startsWith("---")) continue;
+
+      const { attrs } = extract<{ title?: string }>(content);
+      if (typeof attrs.title !== "string") continue;
+
+      await t.step(entry.path, () => {
+        assert(
+          !attrs.title!.includes("`"),
+          `Title contains backticks: "${attrs.title}". Use plain text instead.`,
+        );
+      });
+    }
+  }
+});
+
+Deno.test("CLI command page titles must be just the command name", async (t) => {
+  for await (
+    const entry of walk("./runtime/reference/cli", { exts: [".md"] })
+  ) {
+    const content = await Deno.readTextFile(entry.path);
+    if (!content.startsWith("---")) continue;
+
+    const { attrs } = extract<{ title?: string; command?: string }>(content);
+    if (typeof attrs.command !== "string") continue;
+
+    const expected = `deno ${attrs.command}`;
+
+    await t.step(entry.path, () => {
+      assertEquals(
+        attrs.title,
+        expected,
+        `Title should be "${expected}", got "${attrs.title}". Put descriptions in the "description" field instead.`,
+      );
+    });
+  }
+});

runtime/reference/cli/audit.md

@@ -1,5 +1,5 @@
 ---
-title: "deno audit, audit dependencies for vulnerabilities"
+title: "deno audit"
 command: audit
 openGraphLayout: "/open_graph/cli-commands.jsx"
 openGraphTitle: "deno audit"

runtime/reference/cli/bundle.md

@@ -1,5 +1,5 @@
 ---
-title: "Bundler"
+title: "deno bundle"
 oldUrl: /runtime/manual/cli/bundler/
 command: bundle
 openGraphLayout: "/open_graph/cli-commands.jsx"