Fragments are not recognised inside strings with injected GraphQL language in some cases

[arlampin]

Describe the bug Fragments are not recognised inside strings with injected GraphQL language in some cases.

To Reproduce Using the following text block in TS file

`
    query {
      me {
        ...AuthFragment
      }
    }

    fragment AuthFragment on User {
      email
    }
`;

and then from context actions selecting "Inject language" -> GraphQL.

Everything should be valid, but ...AuthFragment is highlighted with Unknown fragment spread "AuthFragment".

Adding explicit

// language=GraphQL

to the top fixes the issue.

  // language=GraphQL
`
    query {
      me {
        ...AuthFragment
      }
    }

    fragment AuthFragment on User {
      email
    }
`;

The same thing happens in Java files, but there adding language=GraphQL or org.intellij.lang.annotations.Language("GraphQL") annotation doesn't fix the issue.

Expected behavior Valid GraphQL queries should not be marked with errors

Version and Environment Details IDE name and version: IntelliJ IDEA 2023.1.2 (Ultimate Edition) Plugin version: 4.0.1

[nozzlegear]

I've just run into this problem after adding GraphQL support for my .NET package ShopifySharp. Using Rider, fragments aren't recognized inside strings that use .NET's StringSyntaxAttribute, nor does adding the //lang=graphql comment work.

Version and Environment Details IDE name and version: JetBrains Rider 2024.3.5 Plugin version: 243.24978.46

[cmeeren]

I'm hit by this, too. Using F# with StringSyntaxAttribute to trigger language injection. I also get the error if I use Rider's "Edit GraphQL fragment" feature on the injected string.

[erikljung]

Having the same issue in Rider 2025.2.3, plugin version 252.25557.23. Can't seem to suppress the error either.