Add a test for whole module targeting

terraform/transform_targets_test.go

@@ -130,6 +130,77 @@ output.grandchild_id
 	}
 }
 
+// This tests the TargetsTransformer targeting a whole module,
+// rather than a resource within a module instance.
+func TestTargetsTransformer_wholeModule(t *testing.T) {
+	mod := testModule(t, "transform-targets-downstream")
+
+	g := Graph{Path: addrs.RootModuleInstance}
+	{
+		transform := &ConfigTransformer{Config: mod}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("%T failed: %s", transform, err)
+		}
+	}
+
+	{
+		transform := &AttachResourceConfigTransformer{Config: mod}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("%T failed: %s", transform, err)
+		}
+	}
+
+	{
+		transform := &AttachResourceConfigTransformer{Config: mod}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("%T failed: %s", transform, err)
+		}
+	}
+
+	{
+		transform := &OutputTransformer{Config: mod}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("%T failed: %s", transform, err)
+		}
+	}
+
+	{
+		transform := &ReferenceTransformer{}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("err: %s", err)
+		}
+	}
+
+	{
+		transform := &TargetsTransformer{
+			Targets: []addrs.Targetable{
+				addrs.RootModule.
+					Child("child").
+					Child("grandchild"),
+			},
+		}
+		if err := transform.Transform(&g); err != nil {
+			t.Fatalf("%T failed: %s", transform, err)
+		}
+	}
+
+	actual := strings.TrimSpace(g.String())
+	// Even though we only asked to target the grandchild module, all of the
+	// outputs that descend from it are also targeted.
+	expected := strings.TrimSpace(`
+module.child.module.grandchild.aws_instance.foo
+module.child.module.grandchild.output.id
+  module.child.module.grandchild.aws_instance.foo
+module.child.output.grandchild_id
+  module.child.module.grandchild.output.id
+output.grandchild_id
+  module.child.output.grandchild_id
+	`)
+	if actual != expected {
+		t.Fatalf("bad:\n\nexpected:\n%s\n\ngot:\n%s\n", expected, actual)
+	}
+}
+
 func TestTargetsTransformer_destroy(t *testing.T) {
 	mod := testModule(t, "transform-targets-destroy")