Missing deserialization for fragments in query that has the same field multiple times

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Product

Strawberry Shake

Describe the bug

This issue is a bit tricky to describe, please bear with me:

When generating client code for a query that requests the same interface-typed field multiple times (with different arguments, type fragments, and field aliases), the client only includes proper deserialization for the fragment types in whichever field selection is defined first, which causes factory errors.

Steps to reproduce

For example, given a type with an interface-typed field that takes a parameter:

type Example {
  someField(someParameter: String!): ISomeInterface
}

When querying the field multiple times with different arguments and fragments:

query GetMultiple {
  example {
    firstAlias: someField("foo") {
      ... on FirstInterfaceImplementation { someString }
    }
    secondAlias: someField("bar") {
      ... on SecondInterfaceImplementation { someNumber }
    }
  }
}

The generated client will only include deserialization for FirstInterfaceImplementation and will return an error when trying to deserialize data for SecondInterfaceImplementation (this stack trace might not be exactly accurate, I hand-edited it to replace my real identifiers with the example ones):

StrawberryShake.ClientError
{
  Code = "SS1000",
  Exception = System.ArgumentNullException with message "Value cannot be null."
    at Example.GraphQL.Generated.State.GetMultipleResultFactory.MapIGetMultiple_Example_SecondAlias(IISomeInterfaceData data)
    at Example.GraphQL.Generated.State.GetMultipleResultFactory.MapIGetMultiple_Example(ExampleData data)
    at Example.GraphQL.Generated.State.GetMultipleResultFactory.Create(IOperationResultDataInfo dataInfo, IEntityStoreSnapshot snapshot)
    at StrawberryShake.OperationResultBuilder`1.Build(Response`1 response),
  Extensions = {["StackTrace"] = "omitted for brevity"},
  Locations = <null>,
  Message = "Value cannot be null.",
  Path = <null>
}

I've found that we can work around this problem by specifying all desired fragment types in the first selection of the interface-typed field:

query GetMultiple {
  example {
    firstAlias: someField("foo") {
      ... on FirstInterfaceImplementation { someString }
      # This is included here just so it gets included in code generation
      # and can be deserialized in the other field selection below 
      ... on SecondInterfaceImplementation { someNumber }
    }
    secondAlias: someField("bar") {
      ... on SecondInterfaceImplementation { someNumber }
    }
  }
}

Relevant log output

No response

Additional Context?

No response

Version

13.1.0

Start by reproducing the issue with the GraphQL query in the report against Strawberry Shake 13.1.0, then inspect the generated client and GetMultipleResultFactory deserialization paths. Verify that repeated selections of the interface-typed field retain fragment deserialization for both aliases, and confirm that the generated client no longer raises the reported factory error.