docs(useLanguage): add doc comments to hook functions

src/utils/hooks/useLanguage.ts

@@ -7,6 +7,13 @@ import { LanguageObject } from "studio/lib/interfaces/supportedLanguages";
 import { LANGUAGES_QUERY } from "studio/lib/queries/languages";
 import { SLUG_TRANSLATIONS_FROM_LANGUAGE_QUERY } from "studio/lib/queries/slugTranslations";
 
+/**
+ * Client hook providing access to the available Sanity translations for the given slug
+ *
+ * @param currentLanguage the language of the given slug
+ * @param slug slug to translate
+ * @param availableLanguages languages with possible slug translation
+ */
 function useSlugTranslations(
   currentLanguage: LanguageObject | undefined,
   slug: string,
@@ -28,29 +35,38 @@ function useSlugTranslations(
     ).then(setSlugTranslationsData);
   }, [currentLanguage, slug]);
 
-  return (
+  const allSlugTranslations =
     slug === ""
       ? availableLanguages?.map((lang) => ({
           slug: "",
           language: lang.id,
         }))
-      : slugTranslationsData?._translations
-  )
-    ?.filter(
-      (translation) =>
-        translation && translation.language !== currentLanguage?.id,
-    )
-    ?.map(
-      (translation) =>
-        translation && {
-          slug: `/${translation.language}/${translation.slug}`,
-          language: availableLanguages?.find(
-            (lang) => lang.id === translation.language,
-          ),
-        },
-    );
+      : slugTranslationsData?._translations;
+
+  const otherSlugTranslations = allSlugTranslations?.filter(
+    (translation) =>
+      translation && translation.language !== currentLanguage?.id,
+  );
+
+  // include full language object, not just id, in slug translation
+  return otherSlugTranslations?.map(
+    (translation) =>
+      translation && {
+        slug: `/${translation.language}/${translation.slug}`,
+        language: availableLanguages?.find(
+          (lang) => lang.id === translation.language,
+        ),
+      },
+  );
 }
 
+/**
+ * Client hook providing access to:
+ * - the currently selected language from URL
+ * - all enabled languages in Sanity
+ * - default language selected in Sanity
+ * - available translations of the current page slug
+ */
 export default function useLanguage() {
   const pathname = usePathname();