TypeError: parentClass.getInterfaces is not a function

[Joshswooft]

I'm submitting a...

[X] Regression 
[ ] Bug report
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead post your question on Stack Overflow.

Current behavior

Application fails to start.

Stack trace:

(node:23900) UnhandledPromiseRejectionWarning: TypeError: parentClass.getInterfaces is not a function
    at /Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/@nestjs/graphql/dist/schema-builder/factories/object-type-definition.factory.js:56:54
    at resolveThunk (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/definition.js:438:40)
    at defineInterfaces (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/definition.js:619:20)
    at GraphQLObjectType.getInterfaces (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/definition.js:587:31)
    at typeMapReducer (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/schema.js:276:28)
    at typeMapReducer (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/schema.js:286:20)
    at typeMapReducer (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/schema.js:286:20)
    at Array.reduce (<anonymous>)
    at new GraphQLSchema (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/graphql/type/schema.js:145:28)
    at GraphQLSchemaFactory.<anonymous> (/Users/joshuadando/Documents/poc/nest-issue-poc/node_modules/@nestjs/graphql/dist/schema-builder/graphql-schema.factory.js:40:28)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:23900) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 2)
(node:23900) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Similar issue to: #1288

Expected behavior

Application should start, create updated schema and provide a graphql playground to find the store.

Minimal reproduction of the problem with instructions

https://github.com/Joshswooft/nestjs-interface-issue

What is the motivation / use case for changing the behavior?

At our company we have been using nest for over 2 years and are trying to migrate from nest v6 to nestv7. During the migration this was one of the issues we have faced. Note on v6 this functionality was working correctly.

Environment

Nest version: 7.6.11
 
For Tooling issues:
- Node version: v14.15.3
- Platform:  Mac

Others:
Yarn: 1.21.1

[kamilmysliwiec]

Fixed in 7.9.9