TestingOperation.flush expected enum but receive type in `graphql:15`

[magik9907]

Describe the bug
While running tests for the versions listed below, the tests are failing with the error: Cannot read properties of undefined (reading 'SUBSCRIPTION').

Fail location in:

• class TestOperation ,
• method: flush,
• line: 29

Code fragment where it's failed:

if (
    definition.kind === Kind.OPERATION_DEFINITION &&
    definition.operation !== OperationTypeNode.SUBSCRIPTION // <-- PROBLEM
  ) {
    this.complete();
  }

Reference:

• graphql: 16.9.0 --> OperationTypeNode
• graphql: 15.9.0 --> OperationTypeNode

Solution that worked:
After updating graphql to version 16, the tests are now passing

To Reproduce

Steps to reproduce the behavior:
Run test with dependencie version shown below.

Expected behavior

• while installing packages, npm should show information with incompatible version for graphql:15.x.x and apollo-angular:8.*.*
  OR
• while running tests with graphql:15.x.x and apollo-angular:8.*.*, they should passed

Environment:

- apollo-angular@8.0.0
- graphql@15.8.0x

Additional context

[PowerKiKi]

PR are welcome to fix this new limitation. Though I am wondering if we shouldn't just drop support for the old graphql v15 ? 🤔

Was there as specific reason for you to be on v15 ?

[magik9907]

In my case, I didn't see any reason to stay on v15 in project (it looks like it wasn't needed to update it earlier in project). I tested application with graphql:16 and it's worked ok (won't sure for 100% - maybe there is some specific cases but I might not saw it) and I think to keep that version in project.

I think it's good idead to drop support for v15 because there are works on graphql v17.

I have one more doubt, I run test for this project and it failed (for graphql:v15)

But in github actions it passed

I might be wrong, but it might failed only on unit tests but I don't see running unit test with graphql:15 but only e2e.
So, maybe it might good idea to run also additional unit tests for peer dependencies to check compatibility in PR for future changes.