configstruct: make nested config structs work

fs/config/configstruct/configstruct_test.go

@@ -11,12 +11,12 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-type conf struct {
+type Conf struct {
 	A string
 	B string
 }
 
-type conf2 struct {
+type Conf2 struct {
 	PotatoPie      string `config:"spud_pie"`
 	BeanStew       bool
 	RaisinRoll     int
@@ -26,6 +26,14 @@ type conf2 struct {
 	TotalWeight    fs.SizeSuffix
 }
 
+type ConfNested struct {
+	Conf             // embedded struct with no tag
+	Sub1 Conf        `config:"sub"` // member struct with tag
+	Sub2 Conf2       // member struct without tag
+	C    string      // normal item
+	D    fs.Tristate // an embedded struct which we don't want to recurse
+}
+
 func TestItemsError(t *testing.T) {
 	_, err := configstruct.Items(nil)
 	assert.EqualError(t, err, "argument must be a pointer")
@@ -33,8 +41,18 @@ func TestItemsError(t *testing.T) {
 	assert.EqualError(t, err, "argument must be a pointer to a struct")
 }
 
+// Check each item has a Set function pointer then clear it for the assert.Equal
+func cleanItems(t *testing.T, items []configstruct.Item) []configstruct.Item {
+	for i := range items {
+		item := &items[i]
+		assert.NotNil(t, item.Set)
+		item.Set = nil
+	}
+	return items
+}
+
 func TestItems(t *testing.T) {
-	in := &conf2{
+	in := &Conf2{
 		PotatoPie:      "yum",
 		BeanStew:       true,
 		RaisinRoll:     42,
@@ -46,22 +64,64 @@ func TestItems(t *testing.T) {
 	got, err := configstruct.Items(in)
 	require.NoError(t, err)
 	want := []configstruct.Item{
-		{Name: "spud_pie", Field: "PotatoPie", Num: 0, Value: string("yum")},
-		{Name: "bean_stew", Field: "BeanStew", Num: 1, Value: true},
-		{Name: "raisin_roll", Field: "RaisinRoll", Num: 2, Value: int(42)},
-		{Name: "sausage_on_stick", Field: "SausageOnStick", Num: 3, Value: int64(101)},
-		{Name: "forbidden_fruit", Field: "ForbiddenFruit", Num: 4, Value: uint(6)},
-		{Name: "cooking_time", Field: "CookingTime", Num: 5, Value: fs.Duration(42 * time.Second)},
-		{Name: "total_weight", Field: "TotalWeight", Num: 6, Value: fs.SizeSuffix(17 << 20)},
+		{Name: "spud_pie", Field: "PotatoPie", Value: string("yum")},
+		{Name: "bean_stew", Field: "BeanStew", Value: true},
+		{Name: "raisin_roll", Field: "RaisinRoll", Value: int(42)},
+		{Name: "sausage_on_stick", Field: "SausageOnStick", Value: int64(101)},
+		{Name: "forbidden_fruit", Field: "ForbiddenFruit", Value: uint(6)},
+		{Name: "cooking_time", Field: "CookingTime", Value: fs.Duration(42 * time.Second)},
+		{Name: "total_weight", Field: "TotalWeight", Value: fs.SizeSuffix(17 << 20)},
 	}
-	assert.Equal(t, want, got)
+	assert.Equal(t, want, cleanItems(t, got))
+}
+
+func TestItemsNested(t *testing.T) {
+	in := ConfNested{
+		Conf: Conf{
+			A: "1",
+			B: "2",
+		},
+		Sub1: Conf{
+			A: "3",
+			B: "4",
+		},
+		Sub2: Conf2{
+			PotatoPie:      "yum",
+			BeanStew:       true,
+			RaisinRoll:     42,
+			SausageOnStick: 101,
+			ForbiddenFruit: 6,
+			CookingTime:    fs.Duration(42 * time.Second),
+			TotalWeight:    fs.SizeSuffix(17 << 20),
+		},
+		C: "normal",
+		D: fs.Tristate{Value: true, Valid: true},
+	}
+	got, err := configstruct.Items(&in)
+	require.NoError(t, err)
+	want := []configstruct.Item{
+		{Name: "a", Field: "A", Value: string("1")},
+		{Name: "b", Field: "B", Value: string("2")},
+		{Name: "sub_a", Field: "A", Value: string("3")},
+		{Name: "sub_b", Field: "B", Value: string("4")},
+		{Name: "spud_pie", Field: "PotatoPie", Value: string("yum")},
+		{Name: "bean_stew", Field: "BeanStew", Value: true},
+		{Name: "raisin_roll", Field: "RaisinRoll", Value: int(42)},
+		{Name: "sausage_on_stick", Field: "SausageOnStick", Value: int64(101)},
+		{Name: "forbidden_fruit", Field: "ForbiddenFruit", Value: uint(6)},
+		{Name: "cooking_time", Field: "CookingTime", Value: fs.Duration(42 * time.Second)},
+		{Name: "total_weight", Field: "TotalWeight", Value: fs.SizeSuffix(17 << 20)},
+		{Name: "c", Field: "C", Value: string("normal")},
+		{Name: "d", Field: "D", Value: fs.Tristate{Value: true, Valid: true}},
+	}
+	assert.Equal(t, want, cleanItems(t, got))
 }
 
 func TestSetBasics(t *testing.T) {
-	c := &conf{A: "one", B: "two"}
+	c := &Conf{A: "one", B: "two"}
 	err := configstruct.Set(configMap{}, c)
 	require.NoError(t, err)
-	assert.Equal(t, &conf{A: "one", B: "two"}, c)
+	assert.Equal(t, &Conf{A: "one", B: "two"}, c)
 }
 
 // a simple configmap.Getter for testing
@@ -74,17 +134,17 @@ func (c configMap) Get(key string) (value string, ok bool) {
 }
 
 func TestSetMore(t *testing.T) {
-	c := &conf{A: "one", B: "two"}
+	c := &Conf{A: "one", B: "two"}
 	m := configMap{
 		"a": "ONE",
 	}
 	err := configstruct.Set(m, c)
 	require.NoError(t, err)
-	assert.Equal(t, &conf{A: "ONE", B: "two"}, c)
+	assert.Equal(t, &Conf{A: "ONE", B: "two"}, c)
 }
 
 func TestSetFull(t *testing.T) {
-	in := &conf2{
+	in := &Conf2{
 		PotatoPie:      "yum",
 		BeanStew:       true,
 		RaisinRoll:     42,
@@ -102,7 +162,7 @@ func TestSetFull(t *testing.T) {
 		"cooking_time":     "43s",
 		"total_weight":     "18M",
 	}
-	want := &conf2{
+	want := &Conf2{
 		PotatoPie:      "YUM",
 		BeanStew:       false,
 		RaisinRoll:     43,