builder/virtualbox: validate output dir in step, no in config

builder/virtualbox/common/output_config.go

@@ -2,7 +2,6 @@ package common
 
 import (
 	"fmt"
-	"os"
 
 	"github.com/mitchellh/packer/common"
 	"github.com/mitchellh/packer/template/interpolate"
@@ -17,13 +16,5 @@ func (c *OutputConfig) Prepare(ctx *interpolate.Context, pc *common.PackerConfig
 		c.OutputDir = fmt.Sprintf("output-%s", pc.PackerBuildName)
 	}
 
-	var errs []error
-	if !pc.PackerForce {
-		if _, err := os.Stat(c.OutputDir); err == nil {
-			errs = append(errs, fmt.Errorf(
-				"Output directory '%s' already exists. It must not exist.", c.OutputDir))
-		}
-	}
-
-	return errs
+	return nil
 }

builder/virtualbox/common/output_config_test.go

@@ -39,27 +39,7 @@ func TestOutputConfigPrepare_exists(t *testing.T) {
 		PackerForce:     false,
 	}
 	errs := c.Prepare(testConfigTemplate(t), pc)
-	if len(errs) == 0 {
-		t.Fatal("should have errors")
-	}
-}
-
-func TestOutputConfigPrepare_forceExists(t *testing.T) {
-	td, err := ioutil.TempDir("", "packer")
-	if err != nil {
-		t.Fatalf("err: %s", err)
-	}
-	defer os.RemoveAll(td)
-
-	c := new(OutputConfig)
-	c.OutputDir = td
-
-	pc := &common.PackerConfig{
-		PackerBuildName: "foo",
-		PackerForce:     true,
-	}
-	errs := c.Prepare(testConfigTemplate(t), pc)
-	if len(errs) > 0 {
+	if len(errs) != 0 {
 		t.Fatal("should not have errors")
 	}
 }

builder/virtualbox/common/step_output_dir.go

@@ -22,7 +22,16 @@ type StepOutputDir struct {
 func (s *StepOutputDir) Run(state multistep.StateBag) multistep.StepAction {
 	ui := state.Get("ui").(packer.Ui)
 
-	if _, err := os.Stat(s.Path); err == nil && s.Force {
+	if _, err := os.Stat(s.Path); err == nil {
+		if !s.Force {
+			err := fmt.Errorf(
+				"Output directory exists: %s\n\n"+
+					"Use the force flag to delete it prior to building.",
+				s.Path)
+			state.Put("error", err)
+			return multistep.ActionHalt
+		}
+
 		ui.Say("Deleting previous output directory...")
 		os.RemoveAll(s.Path)
 	}

builder/virtualbox/common/step_output_dir_test.go

@@ -45,6 +45,30 @@ func TestStepOutputDir(t *testing.T) {
 	}
 }
 
+func TestStepOutputDir_exists(t *testing.T) {
+	state := testState(t)
+	step := testStepOutputDir(t)
+
+	// Make the dir
+	if err := os.MkdirAll(step.Path, 0755); err != nil {
+		t.Fatalf("bad: %s", err)
+	}
+
+	// Test the run
+	if action := step.Run(state); action != multistep.ActionHalt {
+		t.Fatalf("bad action: %#v", action)
+	}
+	if _, ok := state.GetOk("error"); !ok {
+		t.Fatal("should have error")
+	}
+
+	// Test the cleanup
+	step.Cleanup(state)
+	if _, err := os.Stat(step.Path); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+}
+
 func TestStepOutputDir_cancelled(t *testing.T) {
 	state := testState(t)
 	step := testStepOutputDir(t)