feature (events): add TestWithoutEventing(t) (#2137)

internal/daemon/controller/testing_test.go

@@ -1,7 +1,12 @@
 package controller
 
 import (
+	"bytes"
+	"io"
+	"os"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func Test_TestController(t *testing.T) {
@@ -17,4 +22,44 @@ func Test_TestController(t *testing.T) {
 		defer tc1.Shutdown()
 		defer tc2.Shutdown()
 	})
+	t.Run("controller-without-eventing", func(t *testing.T) {
+		const op = "Test_TestWithoutEventing"
+		assert := assert.New(t)
+
+		// this isn't the best solution for capturing stdout but it works for now...
+		captureFn := func(fn func()) string {
+			old := os.Stdout
+			defer func() {
+				os.Stderr = old
+			}()
+
+			r, w, _ := os.Pipe()
+			os.Stderr = w
+
+			{
+				fn()
+			}
+
+			outC := make(chan string)
+			// copy the output in a separate goroutine so writing to stderr can't block indefinitely
+			go func() {
+				var buf bytes.Buffer
+				io.Copy(&buf, r)
+				outC <- buf.String()
+			}()
+
+			// back to normal state
+			w.Close()
+			return <-outC
+		}
+
+		assert.Empty(captureFn(func() {
+			tc := NewTestController(t, &TestControllerOpts{DisableEventing: true})
+			defer tc.Shutdown()
+		}))
+		assert.NotEmpty(captureFn(func() {
+			tc := NewTestController(t, nil)
+			defer tc.Shutdown()
+		}))
+	})
 }