feat(component-manuscript-manager): throw error when no previous version is found

packages/component-manuscript-manager/src/routes/fragments/patch.js

@@ -17,6 +17,12 @@ module.exports = models => async (req, res) => {
       return res.status(400).json({
         error: `Collection and fragment do not match.`,
       })
+    const fragLength = collection.fragments.length
+    if (fragLength < 2) {
+      return res.status(400).json({
+        error: 'No previous version has been found.',
+      })
+    }
     fragment = await models.Fragment.find(fragmentId)
 
     const authsome = authsomeHelper.getAuthsome(models)
@@ -79,12 +85,7 @@ module.exports = models => async (req, res) => {
       })
     }
 
-    const fragLength = collection.fragments.length
-    if (fragLength < 2) {
-      return res.status(400).json({
-        error: 'No previous version has been found.',
-      })
-    }
+    fragment.save()
 
     const previousFragment = await models.Fragment.find(
       collection.fragments[fragLength - 2],