config/module: failing unit test for GH-1232

config/module/test-fixtures/basic-parent/a/a.tf

@@ -0,0 +1,3 @@
+module "b" {
+    source = "../c"
+}

config/module/test-fixtures/basic-parent/c/c.tf

@@ -0,0 +1 @@
+# Hello

config/module/test-fixtures/basic-parent/main.tf

@@ -0,0 +1,3 @@
+module "a" {
+    source = "./a"
+}

config/module/tree_test.go

@@ -94,6 +94,44 @@ func TestTreeLoad_duplicate(t *testing.T) {
 	}
 }
 
+func TestTreeLoad_parentRef(t *testing.T) {
+	storage := testStorage(t)
+	tree := NewTree("", testConfig(t, "basic-parent"))
+
+	if tree.Loaded() {
+		t.Fatal("should not be loaded")
+	}
+
+	// This should error because we haven't gotten things yet
+	if err := tree.Load(storage, GetModeNone); err == nil {
+		t.Fatal("should error")
+	}
+
+	if tree.Loaded() {
+		t.Fatal("should not be loaded")
+	}
+
+	// This should get things
+	if err := tree.Load(storage, GetModeGet); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if !tree.Loaded() {
+		t.Fatal("should be loaded")
+	}
+
+	// This should no longer error
+	if err := tree.Load(storage, GetModeNone); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	actual := strings.TrimSpace(tree.String())
+	expected := strings.TrimSpace(treeLoadStr)
+	if actual != expected {
+		t.Fatalf("bad: \n\n%s", actual)
+	}
+}
+
 func TestTreeLoad_subdir(t *testing.T) {
 	storage := testStorage(t)
 	tree := NewTree("", testConfig(t, "basic-subdir"))