FieldTypesDoNotMatchException when an optional field with a non-null type has a null value

[marceloverdijk]

null in responses like

"date_of_birth": "1990-03-02",
"date_of_death": null,

are documented in the generated snippets as:

|`date_of_birth`
|`String`
|The date of birth of the driver.

|`date_of_death`
|`Null`
|The date of death of the driver.

When documenting them explicitly like:

                fieldWithPath("date_of_birth")
                        .type(STRING)
                        .description("The date of birth of the driver."),
                fieldWithPath("date_of_death")
                        .type(STRING)
                        .optional()
                        .description("The date of death of the driver."),

gives the error:

org.springframework.restdocs.payload.FieldTypesDoNotMatchException: The documented type of the field 'date_of_death' is String but the actual type is Null

As discussed on Gitter:

Andy Wilkinson @wilkinsona 20:31
I guess it would be reasonable to accept null when a field’s marked as optional

Marcel Overdijk @marceloverdijk 20:31
yes I think so

Andy Wilkinson @wilkinsona 20:31
So in your case a string or null or no field at all would be acceptable as you’ve said the field’s optional
Can you open an issue please? I’d like to do a 1.1.x release soon and I think this could be fixed there

[marceloverdijk]

thx! will try the snapshot later today.

[marceloverdijk]

works like a charm!

[wilkinsona]

Thanks for trying the snapshot, @marceloverdijk