add config modification test

Signed-off-by: Vaughn Dice <[email protected]>

driver/docker/docker_test.go

@@ -5,16 +5,18 @@ import (
 
 	"github.com/cnabio/cnab-go/driver"
 	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/strslice"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestDriver_GetConfigurationOptions(t *testing.T) {
-	d := &Driver{}
 	is := assert.New(t)
-	is.NotNil(d)
-	is.True(d.Handles(driver.ImageTypeDocker))
 
 	t.Run("empty configuration options", func(t *testing.T) {
+		d := &Driver{}
+		is.NotNil(d)
+		is.True(d.Handles(driver.ImageTypeDocker))
+
 		err := d.ApplyConfigurationOptions()
 		is.NoError(err)
 
@@ -28,6 +30,8 @@ func TestDriver_GetConfigurationOptions(t *testing.T) {
 	})
 
 	t.Run("configuration options", func(t *testing.T) {
+		d := &Driver{}
+
 		d.AddConfigurationOptions(func(cfg *container.Config, hostCfg *container.HostConfig) error {
 			cfg.User = "cnabby"
 			hostCfg.Privileged = true
@@ -52,4 +56,30 @@ func TestDriver_GetConfigurationOptions(t *testing.T) {
 		is.NoError(err)
 		is.Equal(expectedHostCfg, hostCfg)
 	})
+
+	t.Run("configuration options - no unintentional modification", func(t *testing.T) {
+		d := &Driver{}
+
+		d.AddConfigurationOptions(func(cfg *container.Config, hostCfg *container.HostConfig) error {
+			hostCfg.CapAdd = strslice.StrSlice{"SUPER_POWERS"}
+			return nil
+		})
+
+		err := d.ApplyConfigurationOptions()
+		is.NoError(err)
+
+		expectedHostCfg := container.HostConfig{
+			CapAdd: strslice.StrSlice{"SUPER_POWERS"},
+		}
+
+		hostCfg, err := d.GetContainerHostConfig()
+		is.NoError(err)
+		is.Equal(expectedHostCfg, hostCfg)
+
+		hostCfg.CapAdd[0] = "NORMAL_POWERS"
+
+		hostCfg, err = d.GetContainerHostConfig()
+		is.NoError(err)
+		is.Equal(expectedHostCfg, hostCfg)
+	})
 }