post-processor/vagrant: test for user variables in vagrantfile_template [GH-1125]

Previously fixed in a4761087

Closes #1125

post-processor/vagrant/post-processor_test.go

@@ -4,6 +4,8 @@ import (
 	"bytes"
 	"compress/flate"
 	"github.com/mitchellh/packer/packer"
+	"io/ioutil"
+	"os"
 	"strings"
 	"testing"
 )
@@ -124,6 +126,41 @@ func TestPostProcessorPostProcess_badId(t *testing.T) {
 	}
 }
 
+func TestPostProcessorPostProcess_vagrantfileUserVariable(t *testing.T) {
+	var p PostProcessor
+
+	f, err := ioutil.TempFile("", "packer")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	defer os.Remove(f.Name())
+
+	c := map[string]interface{}{
+		"packer_user_variables": map[string]string{
+			"foo": f.Name(),
+		},
+
+		"vagrantfile_template": "{{user `foo`}}",
+	}
+	err = p.Configure(c)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	a := &packer.MockArtifact{
+		BuilderIdValue: "packer.parallels",
+	}
+	a2, _, err := p.PostProcess(testUi(), a)
+	if a2 != nil {
+		for _, fn := range a2.Files() {
+			defer os.Remove(fn)
+		}
+	}
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+}
+
 func TestProviderForName(t *testing.T) {
 	if v, ok := providerForName("virtualbox").(*VBoxProvider); !ok {
 		t.Fatalf("bad: %#v", v)