Query not being cleaned up when on Strict Mode

[PierreAndreis]

Intended outcome:
When unmounting a component that uses useQuery, it should clean up even when wrapped by Strict Mode.

Actual outcome:
Updating the cache on which an unmount component depends, generates a react warning about memory leak.

How to reproduce the issue:
https://codesandbox.io/s/nifty-heyrovsky-5cf34
1- Click on "John Smith" and wait for the page to load
2- Click on "Back"
3- Click on "Like" button right by "John Smith"
4- Observe the warning in the console.

Checking on Apollo DevTools, there seems to be more active queries than it should have been after a few times reproducing the issue.

Compared to when Strict mode is not active:

Versions

@apollo/client: 3.3.15
graphql: 15.4.0
react: 17.0.2
react-dom: 17.0.2
react-router-dom: 5.2.0

[PierreAndreis]

Note that this doesn't happen in production build, when strict mode is noop.

[PierreAndreis]

Might be related to #7952 (comment)

[bmviniciuss]

Having the same issue on Strict mode and getting the Can't perform a React state update on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all error.

"dependencies": {
    "@apollo/client": "^3.3.17",
    "graphql": "^15.5.0",
    "react": "^17.0.0",
    "react-dom": "^17.0.0",
    "react-router-dom": "^5.2.0",
    "typescript": "^4.1.2",
    "vite": "^2.3.0"
  }

[6axter82]

Having this warnings in "@apollo/client": "^3.3.19"

[hwillson]

This should be fixed with @apollo/client >= 3.4 - thanks!

[Ralino]

While the warning is gone, I still have the issue that the queries are not cleaned up with @apollo/client 3.4.8 when strict mode is enabled, as shown in this demo: https://codesandbox.io/s/nostalgic-solomon-4stu5

Looking at the active queries with the dev tools, it seems like a query is spawned twice, one with "__typename" queried as well and one without. But only the query with "__typename" is cleaned up. Without strict mode, only a query with "__typename" is spawned (and cleaned up).

[hjrobinson]

I just wanted to note here for anyone using react-router's history to navigate to another page after deleting a document that the memory leak warning went away when I updated to the latest version of @apollo/client (for me this was "@apollo/client": "^3.5.10"). I was previously using version 3.1.4. I needed to restart my application for this to take effect.