Invalid redeclaration of synthesized property '_id'

[jimisaacs]

Summary

I have a rather urgent issue that popped up when trying to use the TestSupport sources. I get the following static compiler error on a MockObject type:

Invalid redeclaration of synthesized property '_id'

The reason seems to be that it's a type in our schema that defines both a _id and a id field, and the codegen outputs that, but Swift doesn't like it.

Version

1.10.0

Steps to reproduce the behavior

Run codegen while generating mocks for a type with both _id and id fields. Then try to use the generated MockObject for that type.

Logs

No response

Anything else?

// @generated
// This file was automatically generated and should not be edited.

import ApolloTestSupport
import MySchema

public class MyGeneratedType: MockObject {
  public static let objectType: ApolloAPI.Object = MyGeneratedSchema.Objects.MyGeneratedType
  public static let _mockFields = MockFields()
  public typealias MockValueCollectionType = Array<Mock<MyGeneratedType>>

  public struct MockFields {
    @Field<MyGeneratedSchema.ID>("_id") public var _id
    @Field<MyGeneratedSchema.ID>("id") public var id
  }
}

public extension Mock where O == MyGeneratedType {
  convenience init(
    _id: MyGeneratedSchema.ID? = nil,
    id: MyGeneratedSchema.ID? = nil
  ) {
    self.init()
    _setScalar(_id, for: \._id)
    _setScalar(id, for: \.id)
  }
}

[jimisaacs]

See https://docs.swift.org/swift-book/documentation/the-swift-programming-language/attributes/#propertyWrapper

[jimisaacs]

I think we might be able to use alias, looking into it.

[AnthonyMDev]

Hmmmm... this is one we haven't seen yet.

I don't think alias is going to help here. If I recall correctly, the test mocks use the field names on the schema, they don't pay attention to the aliases for fields in the operation definitions.

@BobaFetters the work you're doing for changing schema type names doesn't apply to changing the names of fields on the types, right? Just the actual type names themselves?

[jimisaacs]

@AnthonyMDev actually alias seemed to have worked for me. If you feel like this is a bug worth solving please leave this open, or close with documentation guidance for alias.

[jimisaacs]

The alias did this:

// @generated
// This file was automatically generated and should not be edited.

import ApolloTestSupport
import MySchema

public class MyGeneratedType: MockObject {
  public static let objectType: ApolloAPI.Object = MyGeneratedSchema.Objects.MyGeneratedType
  public static let _mockFields = MockFields()
  public typealias MockValueCollectionType = Array<Mock<MyGeneratedType>>

  public struct MockFields {
    @Field<MyGeneratedSchema.ID>("aliasedId") public var aliasedId
    @Field<MyGeneratedSchema.ID>("id") public var id
  }
}

public extension Mock where O == MyGeneratedType {
  convenience init(
    aliasedId: MyGeneratedSchema.ID? = nil,
    id: MyGeneratedSchema.ID? = nil
  ) {
    self.init()
    _setScalar(aliasedId, for: \.aliasedId)
    _setScalar(id, for: \.id)
  }
}

[AnthonyMDev]

Ohhh, okay! I was remembering how that worked incorrectly. Great. That is actually the correct solution to this problem then! Thanks for the update.

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