command: Fix TestPlan_outBackend

We missed fixing this up during the big updates for the new plan/state
models since the failures were being masked by testBackendState being
broken.

This is the same sort of update made to many other tests: add schema to
the mock provider, adjust for the new plan/state types, and make
allowances for the new built-in diffing behavior in core.

command/plan_test.go

@@ -5,7 +5,6 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
-	"reflect"
 	"strings"
 	"sync"
 	"testing"
@@ -16,6 +15,7 @@ import (
 	"github.com/zclconf/go-cty/cty"
 
 	"github.com/hashicorp/terraform/addrs"
+	backendinit "github.com/hashicorp/terraform/backend/init"
 	"github.com/hashicorp/terraform/configs/configschema"
 	"github.com/hashicorp/terraform/helper/copy"
 	"github.com/hashicorp/terraform/plans"
@@ -290,6 +290,9 @@ func TestPlan_outBackend(t *testing.T) {
 						Type: "test_instance",
 						Primary: &terraform.InstanceState{
 							ID: "bar",
+							Attributes: map[string]string{
+								"ami": "bar",
+							},
 						},
 					},
 				},
@@ -305,6 +308,27 @@ func TestPlan_outBackend(t *testing.T) {
 
 	outPath := "foo"
 	p := testProvider()
+	p.GetSchemaReturn = &terraform.ProviderSchema{
+		ResourceTypes: map[string]*configschema.Block{
+			"test_instance": {
+				Attributes: map[string]*configschema.Attribute{
+					"id": {
+						Type:     cty.String,
+						Computed: true,
+					},
+					"ami": {
+						Type:     cty.String,
+						Optional: true,
+					},
+				},
+			},
+		},
+	}
+	p.PlanResourceChangeFn = func(req providers.PlanResourceChangeRequest) providers.PlanResourceChangeResponse {
+		return providers.PlanResourceChangeResponse{
+			PlannedState: req.ProposedNewState,
+		}
+	}
 	ui := cli.NewMockUi()
 	c := &PlanCommand{
 		Meta: Meta{
@@ -326,11 +350,26 @@ func TestPlan_outBackend(t *testing.T) {
 		t.Fatalf("Expected empty plan to be written to plan file, got: %s", spew.Sdump(plan))
 	}
 
-	if plan.Backend.Type == "" || plan.Backend.Config == nil {
-		t.Fatal("should have backend info")
+	if got, want := plan.Backend.Type, "http"; got != want {
+		t.Errorf("wrong backend type %q; want %q", got, want)
 	}
-	if !reflect.DeepEqual(plan.Backend, dataState.Backend) {
-		t.Fatalf("wrong backend config in plan\ngot:  %swant: %s", spew.Sdump(plan.Backend), spew.Sdump(dataState.Backend))
+	if got, want := plan.Backend.Workspace, "default"; got != want {
+		t.Errorf("wrong backend workspace %q; want %q", got, want)
+	}
+	{
+		httpBackend := backendinit.Backend("http")()
+		schema := httpBackend.ConfigSchema()
+		got, err := plan.Backend.Config.Decode(schema.ImpliedType())
+		if err != nil {
+			t.Fatalf("failed to decode backend config in plan: %s", err)
+		}
+		want, err := dataState.Backend.Config(schema)
+		if err != nil {
+			t.Fatalf("failed to decode cached config: %s", err)
+		}
+		if !want.RawEquals(got) {
+			t.Errorf("wrong backend config\ngot:  %#v\nwant: %#v", got, want)
+		}
 	}
 }