Don't expand large diffs by default

[remorses]

Clear and concise description of the problem

Calling toEqual on large objects generates a very large diff error difficult to understand and often cut by the max terminal output length, this can be prevented by passing expand: false to the diff function

Suggested solution

Pass expand: false for large objects and strings

Alternative

Add an expand option in the vitest configuration or always use expand false

Additional context

No response

Validations

• [X] Follow our Code of Conduct
• [X] Read the Contributing Guidelines.
• [X] Read the docs.
• [X] Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[dankolesnikov]

what is the supposed workaround right now? killing my productivity right now. cant see which tests are failing and passing

[sheremet-va]

You can pass down your own diff config - https://vitest.dev/config/#diff

[sheremet-va]

We decided to allow objects in the diff property (it has expand). The documentation should also contain more information about available diff fields.

When it's an object, you can use --diff.expand=false flag or set diff.expand to false in the config:

export default defineConfig({
  test: {
    diff: {
      expand: false,
    },
  },
})