helper/schema: test cases around unknown variable values

helper/schema/provider.go

@@ -23,7 +23,7 @@ type Provider struct {
 	//
 	// The keys of this map are the configuration keys, and the value is
 	// the schema describing the value of the configuration.
-	Schema       map[string]*Schema
+	Schema map[string]*Schema
 
 	// ResourcesMap is the list of available resources that this provider
 	// can manage, along with their Resource structure defining their

helper/schema/schema_test.go

@@ -10,11 +10,12 @@ import (
 
 func TestSchemaMap_Diff(t *testing.T) {
 	cases := []struct {
-		Schema map[string]*Schema
+		Schema          map[string]*Schema
-		State  *terraform.ResourceState
+		State           *terraform.ResourceState
-		Config map[string]interface{}
+		Config          map[string]interface{}
-		Diff   *terraform.ResourceDiff
+		ConfigVariables map[string]string
-		Err    bool
+		Diff            *terraform.ResourceDiff
+		Err             bool
 	}{
 		/*
 		 * String decode
@@ -129,6 +130,68 @@ func TestSchemaMap_Diff(t *testing.T) {
 			Err: false,
 		},
 
+		// Variable (just checking)
+		{
+			Schema: map[string]*Schema{
+				"availability_zone": &Schema{
+					Type:     TypeString,
+					Optional: true,
+				},
+			},
+
+			State: nil,
+
+			Config: map[string]interface{}{
+				"availability_zone": "${var.foo}",
+			},
+
+			ConfigVariables: map[string]string{
+				"var.foo": "bar",
+			},
+
+			Diff: &terraform.ResourceDiff{
+				Attributes: map[string]*terraform.ResourceAttrDiff{
+					"availability_zone": &terraform.ResourceAttrDiff{
+						Old: "",
+						New: "bar",
+					},
+				},
+			},
+
+			Err: false,
+		},
+
+		// Variable computed
+		{
+			Schema: map[string]*Schema{
+				"availability_zone": &Schema{
+					Type:     TypeString,
+					Optional: true,
+				},
+			},
+
+			State: nil,
+
+			Config: map[string]interface{}{
+				"availability_zone": "${var.foo}",
+			},
+
+			ConfigVariables: map[string]string{
+				"var.foo": config.UnknownVariableValue,
+			},
+
+			Diff: &terraform.ResourceDiff{
+				Attributes: map[string]*terraform.ResourceAttrDiff{
+					"availability_zone": &terraform.ResourceAttrDiff{
+						Old: "",
+						New: "${var.foo}",
+					},
+				},
+			},
+
+			Err: false,
+		},
+
 		/*
 		 * Int decode
 		 */
@@ -870,6 +933,12 @@ func TestSchemaMap_Diff(t *testing.T) {
 			t.Fatalf("err: %s", err)
 		}
 
+		if len(tc.ConfigVariables) > 0 {
+			if err := c.Interpolate(tc.ConfigVariables); err != nil {
+				t.Fatalf("err: %s", err)
+			}
+		}
+
 		d, err := schemaMap(tc.Schema).Diff(
 			tc.State, terraform.NewResourceConfig(c))
 		if (err != nil) != tc.Err {