fix(schema-org): avoid crashing from 3+ duplicate nodes

Fixes #669

Author: harlan-zw

packages/schema-org/src/plugin.ts

@@ -128,6 +128,8 @@ export function UnheadSchemaOrg(config: MetaInput = {} as MetaInput, meta: () =>
           const toRemove = new Set<number>()
           for (let i = 0; i < ctx.tags.length; i++) {
             const tag = ctx.tags[i]
+            if (!tag)
+              continue
             if ((tag.props.type === 'application/ld+json' && tag.props.nodes) || tag.key === 'schema-org-graph') {
               delete tag.props.nodes
               if (typeof firstNodeIdx === 'undefined') {

packages/schema-org/test/ssr/dupes.test.ts

@@ -52,4 +52,53 @@ describe('schema.org dupes', () => {
       }</script>"
     `)
   })
+
+  it('handles three or more duplicate schema-org entries without crashing', async () => {
+    const ssrHead = createHead()
+
+    ssrHead.use(UnheadSchemaOrg())
+
+    useHead(ssrHead, {
+      script: [
+        {
+          type: 'application/ld+json',
+          key: 'schema-org-graph',
+          // @ts-expect-error untyped
+          nodes: [
+            defineWebSite({
+              url: '/',
+              inLanguage: 'en',
+              name: 'first',
+            }),
+          ],
+        },
+        {
+          type: 'application/ld+json',
+          key: 'schema-org-graph',
+          // @ts-expect-error untyped
+          nodes: [
+            // @ts-expect-error broken
+            defineWebSite({
+              '@type': 'AboutPage',
+            }),
+          ],
+        },
+        {
+          type: 'application/ld+json',
+          key: 'schema-org-graph',
+          // @ts-expect-error untyped
+          nodes: [
+            defineWebSite({
+              name: 'third',
+            }),
+          ],
+        },
+      ],
+    })
+
+    const data = await renderSSRHead(ssrHead)
+    // should merge all three into a single script tag without throwing
+    expect(data.bodyTags).toContain('"@context": "https://schema.org"')
+    expect(data.bodyTags.match(/application\/ld\+json/g)?.length).toBe(1)
+  })
 })