helper/schema: don't put things into the state that don't exist or are

computed [GH-805]

helper/schema/resource_data.go

@@ -84,8 +84,7 @@ func (d *ResourceData) GetChange(key string) (interface{}, interface{}) {
 }
 
 // GetOk returns the data for the given key and whether or not the key
-// existed or not in the configuration. The second boolean result will also
-// be false if a key is given that isn't in the schema at all.
+// has been set.
 //
 // The first result will not necessarilly be nil if the value doesn't exist.
 // The second result should be checked to determine this information.
@@ -213,9 +212,11 @@ func (d *ResourceData) State() *terraform.InstanceState {
 		}
 
 		raw := d.get([]string{k}, source)
-		rawMap[k] = raw.Value
-		if raw.ValueProcessed != nil {
-			rawMap[k] = raw.ValueProcessed
+		if raw.Exists && !raw.Computed {
+			rawMap[k] = raw.Value
+			if raw.ValueProcessed != nil {
+				rawMap[k] = raw.ValueProcessed
+			}
 		}
 	}
 	mapW := &MapFieldWriter{Schema: d.schema}

helper/schema/resource_data_test.go

@@ -1919,9 +1919,7 @@ func TestResourceDataState(t *testing.T) {
 			Partial: []string{},
 
 			Result: &terraform.InstanceState{
-				Attributes: map[string]string{
-					"availability_zone": "",
-				},
+				Attributes: map[string]string{},
 			},
 		},
 
@@ -1994,9 +1992,7 @@ func TestResourceDataState(t *testing.T) {
 			},
 
 			Result: &terraform.InstanceState{
-				Attributes: map[string]string{
-					"ports.#": "0",
-				},
+				Attributes: map[string]string{},
 			},
 		},
 
@@ -2176,9 +2172,7 @@ func TestResourceDataState(t *testing.T) {
 			Partial: []string{},
 
 			Result: &terraform.InstanceState{
-				Attributes: map[string]string{
-					"ports.#": "0",
-				},
+				Attributes: map[string]string{},
 			},
 		},
 
@@ -2239,6 +2233,31 @@ func TestResourceDataState(t *testing.T) {
 				Attributes: map[string]string{},
 			},
 		},
+
+		// #21
+		{
+			Schema: map[string]*Schema{
+				"foo": &Schema{
+					Type:     TypeString,
+					Optional: true,
+					Computed: true,
+				},
+			},
+
+			State: nil,
+
+			Diff: &terraform.InstanceDiff{
+				Attributes: map[string]*terraform.ResourceAttrDiff{
+					"foo": &terraform.ResourceAttrDiff{
+						NewComputed: true,
+					},
+				},
+			},
+
+			Result: &terraform.InstanceState{
+				Attributes: map[string]string{},
+			},
+		},
 	}
 
 	for i, tc := range cases {