# X_TEST_MODULE_MOCK_UNRESTORABLE

## Means

a mocked module could not be put back at the file boundary

## Typical cause

a test file called mock.module() on a module whose real source threw or did not resolve when loaded for its snapshot, so the next file on this worker would see the fake

## Fix

`x test unit --isolate, or inject the dependency as a parameter instead of mocking the module`

[Testing](/error-codes#testing)