Declaring prop with type `[String!]!` makes it also appear as `String` (possible bug?)

I don’t know if this is a bug or not but I would like, if possible, some clarification on why I’m having this issue.

I have an images that has a type [String!]! but when I try to map it, it appears that it can be of type String. On my initialValues I also have it as an array so I’m not fully understanding where this String comes from. If I step into the autogenerated files I can see that the typing can actually be of type String but why does this happen?

Trying to map over images and seeing that it can be of type String

Checking my mutation to confirm that I only have it as type [String!]!

A useState where the error could be coming from but I’m also declaring it as ['']

The autogenerated variables for my mutation

[ItzaMi]

@dylanwulf, thank you for the help. That made absolute sense!

@brainkim, as @dylanwulf pointed out, it seems like it’s something that is already mentioned on the docs so it probably won’t make much sense to create an issue for that. Anyway, thank you for the help! 🤘

[dylanwulf]

@ItzaMi You understood the question right, the thing I was looking for was the command (graphql-codegen). Your problem is with graphql-code-generator, which is a separate project from apollo-client. Sounds like you want to set arrayInputCoercion to false in your codegen.yml file. https://www.graphql-code-generator.com/docs/plugins/typescript-operations As described in the docs, this option defaults to true because the graphql spec allows both arrays and single primitive values for list inputs. Your server will probably accept either an array or a single string for the images variable. Setting the arrayInputCoercion to false will stop graphql-code-generator from adding | Types.Scalars['String'] to your mutation variable types.