failing test for schemas with a single set attr

Resources with certain combinations of attributes in a nested single set
fail to perperly coerce their shimmed values.

builtin/providers/test/provider.go

@@ -24,6 +24,7 @@ func Provider() terraform.ResourceProvider {
 			"test_resource_diff_suppress":    testResourceDiffSuppress(),
 			"test_resource_force_new":        testResourceForceNew(),
 			"test_resource_nested":           testResourceNested(),
+			"test_resource_nested_set":       testResourceNestedSet(),
 		},
 		DataSourcesMap: map[string]*schema.Resource{
 			"test_data_source":    testDataSource(),

builtin/providers/test/resource_nested_set.go

@@ -0,0 +1,82 @@
+package test
+
+import (
+	"fmt"
+	"math/rand"
+
+	"github.com/hashicorp/terraform/helper/schema"
+)
+
+func testResourceNestedSet() *schema.Resource {
+	return &schema.Resource{
+		Create: testResourceNestedSetCreate,
+		Read:   testResourceNestedSetRead,
+		Delete: testResourceNestedSetDelete,
+		Update: testResourceNestedSetUpdate,
+
+		Importer: &schema.ResourceImporter{
+			State: schema.ImportStatePassthrough,
+		},
+
+		Schema: map[string]*schema.Schema{
+			"optional": {
+				Type:     schema.TypeBool,
+				Optional: true,
+			},
+			"single": {
+				Type:     schema.TypeSet,
+				Optional: true,
+				MaxItems: 1,
+				Elem: &schema.Resource{
+					Schema: map[string]*schema.Schema{
+						"value": {
+							Type:     schema.TypeString,
+							ForceNew: true,
+							Required: true,
+						},
+
+						"optional": {
+							Type:     schema.TypeString,
+							ForceNew: true,
+							Optional: true,
+							Computed: true,
+						},
+					},
+				},
+			},
+		},
+	}
+}
+
+func testResourceNestedSetCreate(d *schema.ResourceData, meta interface{}) error {
+	id := fmt.Sprintf("%x", rand.Int63())
+	d.SetId(id)
+
+	// replicate some awkward handling of a computed value in a set
+	set := d.Get("single").(*schema.Set)
+	l := set.List()
+	if len(l) == 1 {
+		if s, ok := l[0].(map[string]interface{}); ok {
+			if v, _ := s["optional"].(string); v == "" {
+				s["optional"] = id
+			}
+		}
+	}
+
+	d.Set("single", set)
+
+	return testResourceNestedRead(d, meta)
+}
+
+func testResourceNestedSetRead(d *schema.ResourceData, meta interface{}) error {
+	return nil
+}
+
+func testResourceNestedSetDelete(d *schema.ResourceData, meta interface{}) error {
+	d.SetId("")
+	return nil
+}
+
+func testResourceNestedSetUpdate(d *schema.ResourceData, meta interface{}) error {
+	return nil
+}

builtin/providers/test/resource_nested_set_test.go

@@ -0,0 +1,129 @@
+package test
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/hashicorp/terraform/addrs"
+	"github.com/hashicorp/terraform/helper/resource"
+	"github.com/hashicorp/terraform/terraform"
+)
+
+func TestResourceNestedSet_basic(t *testing.T) {
+	resource.UnitTest(t, resource.TestCase{
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckResourceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+	single {
+		value = "bar"
+	}
+}
+				`),
+			},
+		},
+	})
+}
+
+// The set should not be generated because of it's computed value
+func TestResourceNestedSet_noSet(t *testing.T) {
+	checkFunc := func(s *terraform.State) error {
+		root := s.ModuleByPath(addrs.RootModuleInstance)
+		res := root.Resources["test_resource_nested_set.foo"]
+		for k, v := range res.Primary.Attributes {
+			if strings.HasPrefix(k, "single") && k != "single.#" {
+				return fmt.Errorf("unexpected set value: %s:%s", k, v)
+			}
+		}
+		return nil
+	}
+	resource.UnitTest(t, resource.TestCase{
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckResourceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+}
+				`),
+				Check: checkFunc,
+			},
+		},
+	})
+}
+
+func TestResourceNestedSet_addRemove(t *testing.T) {
+	var id string
+	checkFunc := func(s *terraform.State) error {
+		root := s.ModuleByPath(addrs.RootModuleInstance)
+		res := root.Resources["test_resource_nested_set.foo"]
+		if res.Primary.ID == id {
+			return errors.New("expected new resource")
+		}
+		id = res.Primary.ID
+		return nil
+	}
+	resource.UnitTest(t, resource.TestCase{
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckResourceDestroy,
+		Steps: []resource.TestStep{
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+}
+				`),
+				Check: checkFunc,
+			},
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+	single {
+		value = "bar"
+	}
+}
+				`),
+				Check: checkFunc,
+			},
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+}
+				`),
+				Check: checkFunc,
+			},
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+	single {
+		value = "bar"
+	}
+}
+				`),
+				Check: checkFunc,
+			},
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+	single {
+		value = "bar"
+		optional = "baz"
+	}
+}
+				`),
+				Check: checkFunc,
+			},
+
+			resource.TestStep{
+				Config: strings.TrimSpace(`
+resource "test_resource_nested_set" "foo" {
+}
+			   	`),
+				Check: checkFunc,
+			},
+		},
+	})
+}