add chef_environment test

provisioner/chef-client/provisioner_test.go

@@ -22,6 +22,22 @@ func TestProvisioner_Impl(t *testing.T) {
 	}
 }
 
+func TestProvisionerPrepare_chefEnvironment(t *testing.T) {
+	var p Provisioner
+
+	config := testConfig()
+	config["chef_environment"] = "some-env"
+
+	err := p.Prepare(config)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if p.config.ChefEnvironment != "some-env" {
+		t.Fatalf("unexpected: %#v", p.config.ChefEnvironment)
+	}
+}
+
 func TestProvisionerPrepare_configTemplate(t *testing.T) {
 	var err error
 	var p Provisioner