Breaking change in 3.1.5 in `useLazyQuery`

[wild-lotus]

Intended outcome:

Keep my test passing when upgrading @apollo/react-hooks from 3.1.3 to 3.1.5.

Actual outcome:

A bunch of tests started failing. I traced it down to usages of useLazyQuery + useEffect on mount. It seems the first returned state used to be loading, but now it is the previous one (loading: false, data: undefined, error: undefined, I will call this "initial" state).

The breaking change seems to be in 3.1.5.

For the record, we use @apollo/react-testing MockedProvider in the tests.

How to reproduce the issue:

Reproduction CodeSandbox: https://codesandbox.io/s/react-testing-library-demo-8cdgd?file=/src/__tests__/lazy-query-first-state.js

There is a minimal test asserting the first rendered state. Change @apollo/react-hooks dependency version to 3.1.5 and check how the first rendered state changes to the "initial" state and the test starts failing.

In before "use useQuery": I am aware of it, but we cannot change that in our complex codebase for now.

Version

System:
OS: macOS Mojave 10.14.6
Binaries:
Node: 12.16.1 - ~/.nvm/versions/node/v12.16.1/bin/node
Yarn: 1.22.4 - ~/Proyectos/toptal/toptal-core/staff-portal/node_modules/.bin/yarn
npm: 6.14.2 - ~/Proyectos/toptal/toptal-core/staff-portal/node_modules/.bin/npm
Browsers:
Chrome: 83.0.4103.116
Firefox: 78.0.1
Safari: 13.1.1
npmPackages:
@apollo/react-hooks: ^3.1.5 => 3.1.5
@apollo/react-testing: ^3.1.3 => 3.1.3
apollo: ^2.21.2 => 2.25.0
apollo-cache-inmemory: ^1.6.3 => 1.6.6
apollo-client: ^2.6.4 => 2.6.9
apollo-link: ^1.2.13 => 1.2.14
apollo-link-batch-http: ^1.2.13 => 1.2.14
apollo-link-context: ^1.0.19 => 1.0.19
apollo-link-error: ^1.1.12 => 1.1.12
apollo-link-http: ^1.5.16 => 1.5.16
apollo-link-rest: ^0.7.3 => 0.7.3
apollo-link-schema: ^1.2.4 => 1.2.4
apollo-link-token-refresh: ^0.2.7 => 0.2.7

[VincentCATILLON]

I got the same issue with useQuery in my entire tests files using jest fake timers and jest.runOnlyPendingTimers or jest.runAllTimers