Setup and teardown

When your test suits grow large you may need to optimize its execution in order to maintain a productive development environment. One way is to adapt tests to respect the testing.Short flag. Another way is to look for repetitive setups that are time consuming. Setups can be applied at different levels; either before a set of sub tests or an entire package.

For an entire package use the special function TestMain. This is appropriate for setting up databases and after a test run tearing them down.

func TestMain(m *testing.M) {
	// setup before

	code := m.Run()
	defer os.Exit(code)

	// teardown after
}

Be mindful of what you consider to be global setup. The shared setup will force you to design tests with less coupling with other tests. Say you decide to create a database with an initial schema inplace in the setup. Then write operations in your tests must not conflict. This is a good thing, as it allows your tests to be executed against other setups. Cleaning up after each test is also not needed.