terraform: better detection of unknown values in ResourceConfig, tests

terraform/resource.go

@@ -273,6 +273,7 @@ func (c *ResourceConfig) get(
 
 				return nil, false
 			}
+
 			current = v.Interface()
 		case reflect.Slice:
 			previous = current
@@ -298,12 +299,6 @@ func (c *ResourceConfig) get(
 				current = cv.Index(int(i)).Interface()
 			}
 		case reflect.String:
-			// If the value is just the unknown value, then we don't
-			// know anything beyond here.
-			if current == unknownValue() {
-				return current, false
-			}
-
 			// This happens when map keys contain "." and have a common
 			// prefix so were split as path components above.
 			actualKey := strings.Join(parts[i-1:], ".")
@@ -316,6 +311,12 @@ func (c *ResourceConfig) get(
 		}
 	}
 
+	// If the value is just the unknown value, then we don't
+	// know anything beyond here.
+	if current == unknownValue() {
+		return current, false
+	}
+
 	return current, true
 }
 

terraform/resource_test.go

@@ -48,7 +48,7 @@ func TestInstanceInfo(t *testing.T) {
 func TestResourceConfigGet(t *testing.T) {
 	cases := []struct {
 		Config map[string]interface{}
-		Vars   map[string]string
+		Vars   map[string]interface{}
 		Key    string
 		Value  interface{}
 	}{
@@ -70,9 +70,9 @@ func TestResourceConfigGet(t *testing.T) {
 			Config: map[string]interface{}{
 				"foo": "${var.foo}",
 			},
-			Vars:  map[string]string{"foo": "bar"},
+			Vars:  map[string]interface{}{"foo": unknownValue()},
 			Key:   "foo",
-			Value: "bar",
+			Value: "${var.foo}",
 		},
 
 		{
@@ -199,7 +199,12 @@ func TestResourceConfigGet(t *testing.T) {
 		if tc.Vars != nil {
 			vs := make(map[string]ast.Variable)
 			for k, v := range tc.Vars {
-				vs["var."+k] = ast.Variable{Value: v, Type: ast.TypeString}
+				hilVar, err := hil.InterfaceToVariable(v)
+				if err != nil {
+					t.Fatalf("%#v to var: %s", v, err)
+				}
+
+				vs["var."+k] = hilVar
 			}
 
 			if err := rawC.Interpolate(vs); err != nil {
@@ -212,6 +217,8 @@ func TestResourceConfigGet(t *testing.T) {
 
 		// Test getting a key
 		t.Run(fmt.Sprintf("get-%d", i), func(t *testing.T) {
+			t.Logf("Config: %#v", rc)
+
 			v, _ := rc.Get(tc.Key)
 			if !reflect.DeepEqual(v, tc.Value) {
 				t.Fatalf("%d bad: %#v", i, v)