golang-stretchr-testify

Use `require` for fail-fast preconditions to stop test execution immediately and avoid nil panics, while `assert` allows continued verifications to collect multiple failures within a single test.

Use `ErrorIs` for wrapped error checks in testify to correctly verify error chains, ensuring your assertions match the underlying error rather than relying on direct equality comparisons.

Use `EventuallyWithT` for rich async polling assertions in testify, allowing you to evaluate complex conditions over time with proper error reporting instead of manual sleep loops.

Define expectations with `mock.Mock` and verify method calls using `AssertExpectations(t)`, which ensures your mock objects received the expected arguments and were invoked the correct number of times.

Use `testify/suite` to group related tests with shared setup and teardown methods, keeping per-test initialization predictable through `SetupTest` while organizing test logic into structured suites.

Using `assert` for preconditions instead of `require` allows execution to continue after a failure, causing nil panics and misleading follow-up errors; switch to `require` for guard checks.