Code & text
Protobuf FieldMask path algebra
Normalize proto field paths and compare their union and intersection.
Your inputs
Start with an exampleYour result
Example resultAa — A small example of your colors.
How it works
Sort case-sensitive dot-delimited paths, remove duplicates and descendants of selected parent paths, then compute prefix-aware union and intersection.
A selects user and settings.theme. B selects user.name, settings and user_id. Their union is settings/user/user_id; intersection is settings.theme/user.name.
Limits
Up to 10000 paths per mask, 10000 characters and 64 segments per path. Proto field identifiers only: JSON lowerCamel mask strings are not converted. No descriptor, repeated/map-field rule or message-field existence check; this does not apply an API update.