Prisma1: Datamodel types without scalar fields break prisma client generation

[ziegfried]

Describe the bug
When creating a data model type without any scalar fields (ie. only relation fields), code generation breaks.

To Reproduce
Steps to reproduce the behavior:

1. Create a data model type without scalar fields, eg:

type Foobar {
  user: User
}

1. Run prisma generate

$ yarn prisma generate
yarn run v1.10.1
$ /Users/sp/dev/temp/prisma-bug/node_modules/.bin/prisma generate
Generating schema 49ms
 ▸    Syntax Error: Expected Name, found }

Get in touch if you need help: https://www.prisma.io/forum/
To get more detailed output, run $ export DEBUG="*"
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

Expected behavior
No error running the generate command.

Versions:

• prisma CLI: prisma/1.20.1 (darwin-x64) node-v10.10.0

Additional context

Seems like prisma generates an empty input type in this case:

input FoobarUpdateManyMutationInput {

}

and the graphql parser doesn't like that.

[qirex]

Had the same issue with 1.20.1. Rolled back to 1.19.3 because of this.
Previous Issues mentioning similar errors:

• #1981
• #2123
• #3382

[guatedude2]

I'm having the same issue rolled back to 1.20.0 and it worked

[TheYojimbo]

Can confirm what @guatedude2 said, can't generate types without scalar fields with [email protected], works after rolling back to 1.20.0.

[timsuchanek]

This is fixed in 1.20.5. Please let us know if that is not the case and we'll reopen it!

[geroj]

I have same issue with version 1.21.0. I thought that should work after fix in 1.20.5 @timsuchanek

yarn prisma generate with following datamodel works fine:

type FeatureSet implements Node {
  id: ID! @unique
  key: String!
  featureList: [Feature!]!
} 

type Feature implements Node{
  id: ID! @unique
  temp: String!
  featureSetList: [FeatureSet!]!
}

While one where temp attribute is excluded have the same issue as describe above.

type FeatureSet implements Node {
  id: ID! @unique
  key: String!
  featureList: [Feature!]!
} 

type Feature implements Node{
  id: ID! @unique
  featureSetList: [FeatureSet!]!
}