Fix testing errors when module uses ROS context

[laurentboisvert]

Expected Enhancement

Running npm run test should not yield any errors when tests are actually passing.
For example, we run it once:

and then run it again, filtering on powermodule:

The tests pass but errors are output because of the ROS queries.

Current Behavior

Errors because some modules, when tested, try to subscribe to ROS topics.

Possible Solution

There are 3 main solutions:

1. Make the modules as generic as possible, and use a decorator around them that makes the call to ROS. This way, when we test, we only test the wrapped module and not the wrapper that actually calls ROS:

// Example
<ROSSubscriber route="/provider_power/power" messageType="sonia_common/PowerMsg">
  // ROSSubscriber "injects" PowerModule with the message from topics
  <PowerModule />
</ROSSubscriber>

In this example, we would only test <PowerModule /> with dummy datas.
2. Another way would be to add conditional logic in the useROSTopicSubscriber. We could check if we are currently in a test/jest context, with something like

function areWeTestingWithJest() {
    return process.env.JEST_WORKER_ID !== undefined;
}

This way, we don't have to add wrapper components. ⚠️ This is not so easy though because we are using hooks so we can't either return a context or 'nothing'...
3. Another way, not so ideal, is to change the affected components into non-functional components (so they would have more 'lifecycle' methods. The goal would be to use a conditional statement (like method 2) and only subscribe or publish to ROS when we are not testing.

Comments

N/A.

Environment Used

N/A.