Guard against prototype pollution in json0 #14
                
     Merged
            
            
          
  Add this suggestion to a batch that can be applied as a single commit.
  This suggestion is invalid because no changes were made to the code.
  Suggestions cannot be applied while the pull request is closed.
  Suggestions cannot be applied while viewing a subset of changes.
  Only one suggestion per line can be applied in a batch.
  Add this suggestion to a batch that can be applied as a single commit.
  Applying suggestions on deleted lines is not supported.
  You must change the existing code in this line in order to create a valid suggestion.
  Outdated suggestions cannot be applied.
  This suggestion has been applied or marked resolved.
  Suggestions cannot be applied from pending reviews.
  Suggestions cannot be applied on multi-line comments.
  Suggestions cannot be applied while the pull request is queued to merge.
  Suggestion cannot be applied right now. Please check back later.
  
    
  
    
json0.applyhas a prototype pollution security issue, where applying ops with path segments that match prototype property names can clobber said prototype properties. This can cause a DoS by crashing a server running json0. (We've just released safeguards in sharedb, which still uses json0 as the default type.)This fixes the issue by throwing an error in
json0.applywhen encountering a path segment that matches the name of a prototype property.