required properties are not respected when they are missing from properties

[shuluster]

Example schema

type: object
properties: 
  email: 
    type: string
required: ["user"]

should generate a type that requires user to be present. Today it generates a type with only email being the optional argument.

This is part of spec and commonly used for when reusing an object and making optional fields required, for example

LogInReq:
  type: object
  allOf: 
    - $ref: '#/someCommonObject' 
    - type: object
       required: ["user", "password"]

LogInReq now requires user and password to be present while all other fields in someCommonObject to be their default setting.

Working on a PR.

This will change a lot of behavior for the library and curious about people's thoughts.

[drwpow]

This is interesting. I can’t say I’ve used this before, but I don’t see a problem with adding this. Will check out the PR, thanks!

[felixschorer]

This solution doesn't seem to work if exactOptionalPropertyTypes is disabled in the TS Config (it is disabled by default). When the option is enabled, it does work, but breaks when using mapped types.

See these two TS playgrounds.

• exactOptionalPropertyTypes disabled
• exactOptionalPropertyTypes enabled

This could be fixed by introducing an utility type Require<T, RequiredKeys extends PropertyKey>. The fix works with exactOptionalPropertyTypes disabled and enabled.