# X_TEST_SCOPE_UNINSTALLED

## Means

a test double was made in a process the testing preload did not set up

## Typical cause

stub() or swapAdapter() ran with no @ultimat3/testing/preload loaded, so nothing would ever put the double back

## Fix

`add preload = ["@ultimat3/testing/preload"] under [test] in bunfig.toml`

[Testing](/error-codes#testing)