fix: fixes a validation issue with Markdown headings including trailing markup

packages/starlight-links-validator/libs/remark.ts

@@ -56,7 +56,9 @@ export const remarkStarlightLinksValidator: Plugin<[{ base: string; srcDir: URL
             break
           }
 
-          fileHeadings.push(slugger.slug(content))
+          // Remove the last trailing hyphen from the slug like Astro does if it exists.
+          // https://github.com/withastro/astro/blob/74ee2e45ecc9edbe285eadee6d0b94fc47d0d125/packages/integrations/markdoc/src/heading-ids.ts#L21
+          fileHeadings.push(slugger.slug(content).replace(/-$/, ''))
 
           break
         }

packages/starlight-links-validator/tests/fixtures/valid-links/src/content/docs/guides/example.mdx

@@ -47,3 +47,17 @@ some content
 <LinkButton href="/test/">LinkCard: unknown page</LinkButton>
 <LinkButton href="/test/#title">LinkCard: unknown page and hash</LinkButton>
 <LinkButton href="#steps">LinkCard: unknown hash</LinkButton>
+
+import { Badge } from '@astrojs/starlight/components'
+
+## Heading with trailing markup <Badge text="x"/>
+
+- [Link to heading with trailing markup](#heading-with-trailing-markup)
+
+## Heading with trailing markup and content <Badge text="x">Foo</Badge>
+
+- [Link to heading with trailing markup and content](#heading-with-trailing-markup-and-content-foo)
+
+## <Badge text="x"/> <Badge text="x">Foo</Badge> Heading with <Badge text="x"/> <Badge text="x">Foo</Badge> complex markup <Badge text="x">Foo</Badge> <Badge text="x"/> <Badge text="y"/>
+
+- [Link to heading with complex markup](#-foo-heading-with--foo-complex-markup-foo-)

packages/starlight-links-validator/tests/fixtures/valid-links/src/content/docs/index.md

@@ -65,6 +65,12 @@ title: Index
 - [Link reference with query string and hash in this page][ref-with-query-string-and-hash-internal]
 - [Link reference with query string and hash in another page][ref-with-query-string-and-hash-external]
 
+## Trailing markup
+
+- [Link to heading with trailing markup](/guides/example#heading-with-trailing-markup)
+- [Link to heading with trailing markup and content](/guides/example#heading-with-trailing-markup-and-content-foo)
+- [Link to heading with complex markup](/guides/example#-foo-heading-with--foo-complex-markup-foo-)
+
 [ref-with-query-string]: /test?query=string
 [ref-with-query-string-and-hash-internal]: ?query=string#some-links
 [ref-with-query-string-and-hash-external]: /test?query=string#title