fix: allow singleton highlighter recovery after invalid language error (#1091)

Author: Maxiemad

packages/core/src/constructors/bundle-factory.ts

@@ -183,10 +183,15 @@ export function makeSingletonHighlighter<L extends string, T extends string>(
     if (!_shiki) {
       _shiki = createHighlighter({
         ...options,
-        themes: options.themes || [],
-        langs: options.langs || [],
+        themes: [],
+        langs: [],
       })
-      return _shiki
+      const s = await _shiki
+      await Promise.all([
+        s.loadTheme(...(options.themes as T[] || [])),
+        s.loadLanguage(...(options.langs as L[] || [])),
+      ])
+      return s
     }
     else {
       const s = await _shiki

packages/shiki/test/shorthands.test.ts

@@ -67,4 +67,22 @@ describe('should', () => {
         ]
       `)
   })
+
+  it('should allow subsequent valid calls after first invalid language', async () => {
+    const lang = 'invalid'
+    const code = 'console.log("hello")'
+    const theme = 'vitesse-light'
+
+    // First call with invalid language should throw
+    await expect(codeToHtml(code, { lang, theme }))
+      .rejects
+      .toThrow(/Language `invalid` is not included in this bundle/)
+
+    // Subsequent call with valid language should succeed
+    const result = await codeToHtml(code, { lang: 'javascript', theme })
+    expect(result).toBeTruthy()
+    // The HTML contains the code in structured format, check for "console" which appears in the output
+    expect(result).toContain('console')
+    expect(result).toContain('shiki')
+  })
 })