fix(markdown): remove double and trailing dashes from heading ids

src/runtime/markdown-parser/compiler.ts

@@ -20,6 +20,12 @@ export default function (this: any, _options: MarkdownOptions) {
     if (Array.isArray(node)) {
       return node.map(parseAsJSON).filter(Boolean)
     }
+
+    // Remove double dashes and trailing dash from heading ids
+    if (node.tagName?.startsWith('h') && node.properties.id) {
+      node.properties.id = node.properties.id.replace(/-+/g, '-').replace(/-$/, '')
+    }
+
     /**
      * Element node creates an isolated children array to
      * allow nested elements

test/features/parser-markdown.ts

@@ -179,5 +179,22 @@ export const testMarkdownParser = () => {
       expect(nodes.shift().props.href).toEqual('../../foo')
       expect(nodes.shift().props.href).toEqual('../../_foo')
     })
+
+    test('No trailing dashes in heading ids', async () => {
+      const parsed = await $fetch('/api/parse', {
+        method: 'POST',
+        body: {
+          id: 'content:index.md',
+          content: [
+            '# `<Alert />` ',
+            '## `<Alert />` -',
+            '### `<Alert />` \\#',
+            '### `<Alert />`.'
+          ].join('\n')
+        }
+      })
+      expect(parsed.body.children[0].props.id).toEqual('alert')
+      expect(parsed.body.children[1].props.id).toEqual('alert')
+    })
   })
 }