add better generate

Signed-off-by: Jess Frazelle <acidburn@microsoft.com>

vendor/github.com/docker/cli/internal/test/environment/testenv.go

@@ -0,0 +1,21 @@
+package environment
+
+import (
+	"os"
+	"time"
+
+	"github.com/gotestyourself/gotestyourself/poll"
+	"github.com/pkg/errors"
+)
+
+// Setup a new environment
+func Setup() error {
+	dockerHost := os.Getenv("TEST_DOCKER_HOST")
+	if dockerHost == "" {
+		return errors.New("$TEST_DOCKER_HOST must be set")
+	}
+	return os.Setenv("DOCKER_HOST", dockerHost)
+}
+
+// DefaultPollSettings used with gotestyourself/poll
+var DefaultPollSettings = poll.WithDelay(100 * time.Millisecond)