terraform: test for ResourceAddress.stateId()

terraform/resource_address.go

@@ -88,7 +88,6 @@ func (r *ResourceAddress) String() string {
 // stateId returns the ID that this resource should be entered with
 // in the state. This is also used for diffs. In the future, we'd like to
 // move away from this string field so I don't export this.
-// TODO: test
 func (r *ResourceAddress) stateId() string {
 	result := fmt.Sprintf("%s.%s", r.Type, r.Name)
 	switch r.Mode {

terraform/resource_address_test.go

@@ -521,3 +521,52 @@ func TestResourceAddressEquals(t *testing.T) {
 		}
 	}
 }
+
+func TestResourceAddressStateId(t *testing.T) {
+	cases := map[string]struct {
+		Input    *ResourceAddress
+		Expected string
+	}{
+		"basic resource": {
+			&ResourceAddress{
+				Mode:         config.ManagedResourceMode,
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+			"aws_instance.foo",
+		},
+
+		"basic resource ignores count": {
+			&ResourceAddress{
+				Mode:         config.ManagedResourceMode,
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        2,
+			},
+			"aws_instance.foo",
+		},
+
+		"data resource": {
+			&ResourceAddress{
+				Mode:         config.DataResourceMode,
+				Type:         "aws_instance",
+				Name:         "foo",
+				InstanceType: TypePrimary,
+				Index:        -1,
+			},
+			"data.aws_instance.foo",
+		},
+	}
+
+	for tn, tc := range cases {
+		t.Run(tn, func(t *testing.T) {
+			actual := tc.Input.stateId()
+			if actual != tc.Expected {
+				t.Fatalf("bad: %q\n\nexpected: %s\n\ngot: %s", tn, tc.Expected, actual)
+			}
+		})
+	}
+}