README.md

• The check Package
  • Example Usage
  • Custom Assertions

The check Package

The check package is designed for performing assertions in Go tests, particularly as a foundational layer for the assert package. It provides functions that return errors instead of boolean values, allowing callers to adjust error messages to a particular context, add more contextual information about the check, improving assertion message comprehension.

Example Usage

You use checks like any other function returning error.

have := errors.New("test error")

err := check.NoError(have, check.WithTrail("type.field"))

fmt.Println(err)
// Output:
// expected the error to be nil:
//   trail: type.field
//    want: nil
//    have: "test error"

The main purpose of returning an error from a check, instead of true false like it is in case of assert package is to allow user to customize the message and/or add context.

have := errors.New("test error")

err := check.NoError(have, check.WithTrail("type.field"))

err = notice.From(err, "prefix").Append("context", "wow")

fmt.Println(err)
// Output:
// [prefix] expected the error to be nil:
//     trail: type.field
//      want: nil
//      have: "test error"
//   context: wow

Custom Assertions

See example in custom_assertions_test.go file.