Regression v16: typeInfo.getFieldDef() missing description 🐛

[simlu]

In version 16.x we are no longer getting the description returned as expected. I've put together a small test case.

This works fine with 15.x

import assert from 'assert';
import {
  parse, TypeInfo, validate, visit, visitWithTypeInfo
} from 'graphql';
import { makeExecutableSchema } from '@graphql-tools/schema';

// schemas as defined by server
const schema = makeExecutableSchema({
  typeDefs: [
    'type Notification {',
    '  # some description',
    '  id: ID',
    '}',
    'type Query { Notification: Notification }'
  ].join('\n'),
  parseOptions: {
    commentDescriptions: true
  }
});
// ast as defined by query
const ast = parse('query Notification { Notification { id } }');

// making sure everything is fine
const errors = validate(schema, ast);
assert(errors.length === 0);

// the actually changed behavior below
const typeInfo = new TypeInfo(schema);
visit(ast, visitWithTypeInfo(typeInfo, {
  enter(node, key, parent, path, ancestors) {
    const fieldDef = typeInfo.getFieldDef();
    if (fieldDef?.name === 'id') {
      console.log([key, fieldDef?.description]);
    }
  }
}));
// => [ 0, 'some description' ]
// => [ 'name', 'some description' ]

but with 16.x we are getting back

// => [ 0, undefined ]
// => [ 'name', undefined ]

[simlu]

It looks like comment descriptions were deprecated and are now completely removed as per #2900