Reduce output for custom objects when using toHaveLength matcher

[eddyerburgh]

🚀 Feature Proposal

Remove the received output for custom objects that fail a toHaveLength matcher assertion.

Motivation

If you use toHaveLength on a custom object, like an enzyme Wrapper, the output logs all the properties of the object. This makes tests difficult to read.

Example

The same way as before, but no received logging for objects that aren't an Array.

Pitch

Appropriate custom matchers make failing tests more expressive, but error messages for custom objects with toHaveLength are too verbose. It makes failing tests less expressive.

[greypants]

YES PLEASE! This is out of control:

[greypants]

To be fair, you can opt out of this, and just expect(thing.length).toBe(0)

[mattphillips]

A quick win might be to remove the Received output all together and instead have:

Expected value to have length:
  n
Received length:
  m

A slightly more complicated but better alternative could be to use process.stdout.columns to determine how wide the users terminal is and only print the first N characters of the stringified received value :)

[SimenB]

@pedrottimark are you fixing this in your PR?

[johanjq]

@greypants thanks for this man, you are amazing

[github-actions]

This issue is stale because it has been open for 1 year with no activity. Remove stale label or comment or this will be closed in 14 days.

[github-actions]

This issue was closed because it has been stalled for 7 days with no activity. Please open a new issue if the issue is still relevant, linking to this one.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.
Please note this issue tracker is not a help forum. We recommend using StackOverflow or our discord channel for questions.