helper/resource: can specify specific name to id refresh test

helper/resource/testing.go

@@ -179,6 +179,14 @@ func Test(t TestT, c TestCase) {
 			// Find the first non-nil resource in the state
 			for _, m := range state.Modules {
 				if len(m.Resources) > 0 {
+					if c.IDRefreshName != "" {
+						if v, ok := m.Resources[c.IDRefreshName]; ok {
+							idRefreshCheck = v
+						}
+
+						break
+					}
+
 					for _, v := range m.Resources {
 						if v != nil && v.Primary != nil {
 							idRefreshCheck = v

helper/resource/testing_test.go

@@ -145,6 +145,58 @@ func TestTest_idRefresh(t *testing.T) {
 	}
 }
 
+func TestTest_idRefreshCustomName(t *testing.T) {
+	// Refresh count should be 3:
+	//   1.) initial Ref/Plan/Apply
+	//   2.) post Ref/Plan/Apply for plan-check
+	//   3.) id refresh check
+	var expectedRefresh int32 = 3
+
+	mp := testProvider()
+	mp.DiffReturn = nil
+
+	mp.ApplyFn = func(
+		info *terraform.InstanceInfo,
+		state *terraform.InstanceState,
+		diff *terraform.InstanceDiff) (*terraform.InstanceState, error) {
+		if !diff.Destroy {
+			return &terraform.InstanceState{
+				ID: "foo",
+			}, nil
+		}
+
+		return nil, nil
+	}
+
+	var refreshCount int32
+	mp.RefreshFn = func(*terraform.InstanceInfo, *terraform.InstanceState) (*terraform.InstanceState, error) {
+		atomic.AddInt32(&refreshCount, 1)
+		return &terraform.InstanceState{ID: "foo"}, nil
+	}
+
+	mt := new(mockT)
+	Test(mt, TestCase{
+		IDRefreshName: "test_instance.foo",
+		Providers: map[string]terraform.ResourceProvider{
+			"test": mp,
+		},
+		Steps: []TestStep{
+			TestStep{
+				Config: testConfigStr,
+			},
+		},
+	})
+
+	if mt.failed() {
+		t.Fatalf("test failed: %s", mt.failMessage())
+	}
+
+	// See declaration of expectedRefresh for why that number
+	if refreshCount != expectedRefresh {
+		t.Fatalf("bad refresh count: %d", refreshCount)
+	}
+}
+
 func TestTest_idRefreshDisable(t *testing.T) {
 	mp := testProvider()
 	mp.DiffReturn = nil