shuffler

Overview ¶

Package shuffler primarily provides the Suite struct that functions as a test runner and randomizer when embedded in your test struct. Methods defined on your suite struct will be resolved at runtime, and all tests that start with Test will be run. However, the key thing is that the test resolution will also randomize the order of the tests in the suite.

The shuffler package also supports a command line flag to set the randomization seed. By default it uses time.Now().UnixNano(), but you can also set it by passing in `-shuffler.seed=<int>`. The seed used is always logged in the test output.

Caveat: The shuffler package only works for writing testing.T tests. If you

are writing benchmarks, please do not use this package. Also, it is
strongly recommended to not use this with t.Parallel().

An example:

import (
    "github.com/gobox/pkg/shuffler"
    "github.com/stretchr/testify/assert"
)

// Define your suite struct, and embed it to get the predefined functionality
type YourTestSuite struct {
    shuffler.Suite
    Capacitors []Capacitor
}

// Any method that starts with Test will be run by the test suite, just
// like in the testing package
func (s *YourTestSuite) TestThatWeFluxCapacitors(t *testing.T) {
    f := NewFluxer()
    f.Flux(s.Capacitors)
    for c, _ := range s.Capacitors {
        assert.True(t, c.HasBeenFluxed)
    }
}

// Finally, you have to define one traditional test method to act as the
// equivalent of a TestMain(m *testing.M) function in the testing module
func TestCapacitorSuite(t *testing.T) {
    shuffler.Run(t, new(YourTestSuite))
}

Deprecated: Test shuffling is supported out of the box in Go 1.17 and later via the -shuffle flag. Use native go test functionality instead of this package.

Description: Provides helpers for creating a shuffler test suite