Parallel execution

Parallelism

It is possible to run multiple tests with mockio in parallel using the --parallel option. This option is available in the test and run commands.

Concurrency

Library supports invoking stubbed methods from different goroutine.

Go

func TestParallelSuccess(t *testing.T) {
    SetUp(t)
    greeter := Mock[Greeter]()
    wg := sync.WaitGroup{}
    wg.Add(2)
    When(greeter.Greet("John")).ThenReturn("hello world")
    go func() {
        greeter.Greet("John")
        wg.Done()
    }()
    go func() {
        greeter.Greet("John")
        wg.Done()
    }()
    wg.Wait()
    Verify(greeter, Times(2)).Greet("John")
}

However, library does not support stubbing methods from different goroutine. This test will result in error:

Go

func TestParallelFail(t *testing.T) {
    SetUp(t)
    greeter := Mock[Greeter]()
    wg := sync.WaitGroup{}
    wg.Add(2)
    go func() {
        When(greeter.Greet("John")).ThenReturn("hello world")
        wg.Done()
    }()
    go func() {
        When(greeter.Greet("John")).ThenReturn("hello world")
        wg.Done()
    }()
    wg.Wait()
    if greeter.Greet("John") != "hello world" {
        t.Error("Expected 'hello world'")
    }
}

The main rule is that call to When should be in the same goroutine in which the mock is created.

Also, each time you create a mock in a newly created goroutine, you need to call SetUp(t) again to initialize the mockio library in that goroutine.

Go

func TestParallelSuccess(t *testing.T) {
    SetUp(t)
    wg := sync.WaitGroup{}
    wg.Add(1)
    go func() {
        SetUp(t)
        greeter := Mock[Greeter]()
        When(greeter.Greet("John")).ThenReturn("hello world")
        wg.Done()
    }()
    wg.Wait()
}