I'm looking for a paid tool or open source project that validates a zipped package locally before attempting to deploy it to a salesforce sandbox or production environment.
By validation I mean to validate the metadata consistency in a specific deployment. As an example, I want to be able to validate that for all translations in the translation file, there exist corresponding custom labels in the custom labels file. Other examples could be apex code referencing fields in the model or layout referencing fields.
The reason for this request is to left-shift deployment issues, in order to tackle them sooner and closer to the point in time where you create the deployment.