fixed infinite recursion

CHANGELOG.md

@@ -6,6 +6,10 @@ and this project try to adheres to [Semantic Versioning](https://semver.org/),
 but not always is possible (due the use of unstable features from Deno).
 Any BREAKING CHANGE between minor versions will be documented here in upper case.
 
+## [Unreleased]
+### Fixed
+- Infinite recursion of `multilanguage` plugin combined with pagination with the returnPageData option as `true`.
+
 ## [1.19.4] - 2023-11-27
 ### Fixed
 - Tailwind: Fix types for `options`.
@@ -2480,6 +2484,7 @@ The first version.
 [#504]: https://github.com/lumeland/lume/issues/504
 [#514]: https://github.com/lumeland/lume/issues/514
 
+[Unreleased]: https://github.com/lumeland/lume/compare/v1.19.4...HEAD
 [1.19.4]: https://github.com/lumeland/lume/compare/v1.19.3...v1.19.4
 [1.19.3]: https://github.com/lumeland/lume/compare/v1.19.2...v1.19.3
 [1.19.2]: https://github.com/lumeland/lume/compare/v1.19.1...v1.19.2

plugins/multilanguage.ts

@@ -41,7 +41,7 @@ export default function multilanguage(userOptions?: Partial<Options>): Plugin {
 
       // Create a new page per language
       const newPages: Page[] = [];
-      const id: string = data.id || page.src.path.slice(1);
+      const id: string | number = data.id ?? page.src.path.slice(1);
       const basePath: string = typeof page.data.url === "string"
         ? posix.dirname(page.data.url)
         : "";
@@ -194,10 +194,18 @@ function filterLanguage(
       continue;
     }
 
+    if (value instanceof Page) {
+      continue;
+    }
+
+    // @ts-ignore: avoid recursive filtering of pages
     if (isPlainObject(value)) {
       result[name] = filterLanguage(langs, lang, value);
     } else if (Array.isArray(value)) {
       result[name] = value.map((item) => {
+        if (item instanceof Page) {
+          return item;
+        }
         return isPlainObject(item) ? filterLanguage(langs, lang, item) : item;
       });
     } else {