Panic when compiling Sandbox's introspection result

[lennyburdette]

Description

When creating a compiler using the operation body within an Apollo Router plugin, I get a panic on introspection requests from Apollo Sandbox.

Steps to reproduce

Failing test: https://github.com/apollographql/apollo-rs/pull/279

Expected result

The operation is successfully compiled.

Actual result

Router logs:

2022-08-15T20:40:57.157611Z ERROR request{method=POST uri=/ version=HTTP/1.1 otel.kind=server otel.status_code=}: apollo_router::executable: panicked at 'Internal error, cycle detected:

DatabaseKeyIndex { group_index: 0, query_index: 8, key_index: 0 }
DatabaseKeyIndex { group_index: 0, query_index: 23, key_index: 1 }
', /Users/lenny/.cargo/registry/src/github.com-1ecc6299db9ec823/salsa-0.16.1/src/lib.rs:490:48

Environment

• Crate version: [email protected], [email protected]

[lennyburdette]

I started commenting out things until it worked. It seems like this is just a nested fragment issue. This operation triggers the same result:

query IntrospectionQuery {
  foo {
    ...Bar
  }
}

fragment Bar on Foo {
  baz {
    ...Quux
  }
}

fragment Quux on Baz {
  id
}

[lrlna]

ah perfect! love a good reproduceable example. a fix is incoming