From 597b7ad8c53af772c775da453db1d56120faf2c2 Mon Sep 17 00:00:00 2001
From: Matthew Hooker <mwhooker@gmail.com>
Date: Wed, 8 Mar 2017 23:43:38 -0800
Subject: [PATCH] builder/hyper-v: validate output dir in step, not in config

essentially same work as #2233
---
 builder/hyperv/common/output_config.go      | 12 ++----------
 builder/hyperv/common/output_config_test.go |  7 ++++---
 builder/hyperv/common/step_output_dir.go    | 20 +++++++++++++++++++-
 3 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/builder/hyperv/common/output_config.go b/builder/hyperv/common/output_config.go
index ee589d49d..7b5ddcd45 100644
--- a/builder/hyperv/common/output_config.go
+++ b/builder/hyperv/common/output_config.go
@@ -2,9 +2,9 @@ package common
 
 import (
 	"fmt"
+
 	"github.com/mitchellh/packer/common"
 	"github.com/mitchellh/packer/template/interpolate"
-	"os"
 )
 
 type OutputConfig struct {
@@ -16,13 +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
 }
diff --git a/builder/hyperv/common/output_config_test.go b/builder/hyperv/common/output_config_test.go
index ebd91eab1..3da8bda58 100644
--- a/builder/hyperv/common/output_config_test.go
+++ b/builder/hyperv/common/output_config_test.go
@@ -1,10 +1,11 @@
 package common
 
 import (
-	"github.com/mitchellh/packer/common"
 	"io/ioutil"
 	"os"
 	"testing"
+
+	"github.com/mitchellh/packer/common"
 )
 
 func TestOutputConfigPrepare(t *testing.T) {
@@ -39,7 +40,7 @@ func TestOutputConfigPrepare_exists(t *testing.T) {
 		PackerForce:     false,
 	}
 	errs := c.Prepare(testConfigTemplate(t), pc)
-	if len(errs) == 0 {
-		t.Fatal("should have errors")
+	if len(errs) != 0 {
+		t.Fatal("should not have errors")
 	}
 }
diff --git a/builder/hyperv/common/step_output_dir.go b/builder/hyperv/common/step_output_dir.go
index 209bbabe2..1443e5791 100644
--- a/builder/hyperv/common/step_output_dir.go
+++ b/builder/hyperv/common/step_output_dir.go
@@ -17,16 +17,30 @@ import (
 type StepOutputDir struct {
 	Force bool
 	Path  string
+
+	cleanup bool
 }
 
 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)
 	}
 
+	// Enable cleanup
+	s.cleanup = true
+
 	// Create the directory
 	if err := os.MkdirAll(s.Path, 0755); err != nil {
 		state.Put("error", err)
@@ -47,6 +61,10 @@ func (s *StepOutputDir) Run(state multistep.StateBag) multistep.StepAction {
 }
 
 func (s *StepOutputDir) Cleanup(state multistep.StateBag) {
+	if !s.cleanup {
+		return
+	}
+
 	_, cancelled := state.GetOk(multistep.StateCancelled)
 	_, halted := state.GetOk(multistep.StateHalted)