Quote powershell so that it does not try to interpret command to be run

Get VName out of state. This allows template replacement to be run on vmname

builder/hyperv/common/step_type_boot_command.go

@@ -32,15 +32,14 @@ type bootCommandTemplateData struct {
 type StepTypeBootCommand struct {
 	BootCommand []string
 	SwitchName  string
-	VMName      string
 	Ctx         interpolate.Context
 }
 
 func (s *StepTypeBootCommand) Run(state multistep.StateBag) multistep.StepAction {
 	httpPort := state.Get("http_port").(uint)
 	ui := state.Get("ui").(packer.Ui)
-
 	driver := state.Get("driver").(Driver)
+	vmName := state.Get("vmName").(string)
 
 	hostIp, err := driver.GetHostAdapterIpAddressForSwitch(s.SwitchName)
 
@@ -56,7 +55,7 @@ func (s *StepTypeBootCommand) Run(state multistep.StateBag) multistep.StepAction
 	s.Ctx.Data = &bootCommandTemplateData{
 		hostIp,
 		httpPort,
-		s.VMName,
+		vmName,
 	}
 
 	ui.Say("Typing the boot command...")
@@ -77,7 +76,7 @@ func (s *StepTypeBootCommand) Run(state multistep.StateBag) multistep.StepAction
 
 	scanCodesToSendString := strings.Join(scanCodesToSend, " ")
 
-	if err := driver.TypeScanCodes(s.VMName, scanCodesToSendString); err != nil {
+	if err := driver.TypeScanCodes(vmName, scanCodesToSendString); err != nil {
 		err := fmt.Errorf("Error sending boot command: %s", err)
 		state.Put("error", err)
 		ui.Error(err.Error())

builder/hyperv/iso/builder.go

@@ -148,8 +148,8 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
 	}
 
 	if b.config.VMName == "" {
-		b.config.VMName = fmt.Sprintf("packer-%s", b.config.PackerBuildName)
-	}
+		b.config.VMName = fmt.Sprintf("packer-%s-{{timestamp}}", b.config.PackerBuildName)
+	}	
 
 	log.Println(fmt.Sprintf("%s: %v", "VMName", b.config.VMName))
 
@@ -311,7 +311,6 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
 		&hypervcommon.StepTypeBootCommand{
 			BootCommand: b.config.BootCommand,
 			SwitchName:  b.config.SwitchName,
-			VMName:      b.config.VMName,
 			Ctx:         b.config.ctx,
 		},
 

provisioner/powershell/provisioner.go

@@ -116,11 +116,11 @@ func (p *Provisioner) Prepare(raws ...interface{}) error {
 	}
 
 	if p.config.ElevatedEnvVarFormat == "" {
-		p.config.ElevatedEnvVarFormat = `$env:%s="%s"; `
+		p.config.ElevatedEnvVarFormat = `$env:%s=\"%s\"; `
 	}
 
 	if p.config.ExecuteCommand == "" {
-		p.config.ExecuteCommand = `powershell "& { {{.Vars}}{{.Path}}; exit $LastExitCode}"`
+		p.config.ExecuteCommand = `powershell '& { {{.Vars}}{{.Path}}; exit $LastExitCode}'`
 	}
 
 	if p.config.ElevatedExecuteCommand == "" {

provisioner/powershell/provisioner_test.go

@@ -75,8 +75,8 @@ func TestProvisionerPrepare_Defaults(t *testing.T) {
 		t.Error("expected elevated_password to be empty")
 	}
 
-	if p.config.ExecuteCommand != "powershell \"& { {{.Vars}}{{.Path}}; exit $LastExitCode}\"" {
-		t.Fatalf("Default command should be powershell \"& { {{.Vars}}{{.Path}}; exit $LastExitCode}\", but got %s", p.config.ExecuteCommand)
+	if p.config.ExecuteCommand != "powershell '& { {{.Vars}}{{.Path}}; exit $LastExitCode}'" {
+		t.Fatalf("Default command should be powershell '& { {{.Vars}}{{.Path}}; exit $LastExitCode}', but got %s", p.config.ExecuteCommand)
 	}
 
 	if p.config.ElevatedExecuteCommand != "{{.Vars}}{{.Path}}" {