Handle Table

internal/ast/ast.go

@@ -129,23 +129,29 @@ type Node struct {
 	// InlineTables have one child per key-value pair in the table.
 	// KeyValues have at least two children. The last one is the value. The
 	// rest make a potentially dotted key.
+	// Table and Array table have one child per element of the key they
+	// represent (same as KeyValue, but without the last node being the value).
 	Children []Node
 }
 
 var NoNode = Node{}
 
-// Key returns the nodes making the Key of a KeyValue.
+// Key returns the child nodes making the Key on a supported node. Panics
+// otherwise.
 // They are guaranteed to be all be of the Kind Key. A simple key would return
 // just one element.
-// Panics if not called on a KeyValue node, or if the Children are malformed.
 func (n *Node) Key() []Node {
-	if n.Kind != KeyValue {
-		panic(fmt.Errorf("Key() should only be called on on a KeyValue, not %s", n.Kind))
+	switch n.Kind {
+	case KeyValue:
+		if len(n.Children) < 2 {
+			panic(fmt.Errorf("KeyValue should have at least two children, not %d", len(n.Children)))
+		}
+		return n.Children[:len(n.Children)-1]
+	case Table:
+		return n.Children
+	default:
+		panic(fmt.Errorf("Key() is not supported on a %s", n.Kind))
 	}
-	if len(n.Children) < 2 {
-		panic(fmt.Errorf("KeyValue should have at least two children, not %d", len(n.Children)))
-	}
-	return n.Children[:len(n.Children)-1]
 }
 
 // Value returns a pointer to the value node of a KeyValue.

internal/unmarshaler/unmarshaler.go

@@ -7,19 +7,28 @@ import (
 	"github.com/pelletier/go-toml/v2/internal/ast"
 )
 
-func FromAst(tree ast.Root, target interface{}) error {
-	v := reflect.ValueOf(target)
-	if v.Kind() != reflect.Ptr {
-		return fmt.Errorf("need to target a pointer, not %s", v.Kind())
+func Unmarshal(data []byte, v interface{}) error {
+	p := parser{}
+	err := p.parse(data)
+	if err != nil {
+		return err
 	}
-	if v.IsNil() {
+	return fromAst(p.tree, v)
+}
+
+func fromAst(tree ast.Root, v interface{}) error {
+	r := reflect.ValueOf(v)
+	if r.Kind() != reflect.Ptr {
+		return fmt.Errorf("need to target a pointer, not %s", r.Kind())
+	}
+	if r.IsNil() {
 		return fmt.Errorf("target pointer must be non-nil")
 	}
 
-	x := valueTarget(v.Elem())
-
+	var x target = valueTarget(r.Elem())
+	var err error
 	for _, node := range tree {
-		err := unmarshalTopLevelNode(x, &node)
+		x, err = unmarshalTopLevelNode(x, &node)
 		if err != nil {
 			return err
 		}
@@ -28,31 +37,39 @@ func FromAst(tree ast.Root, target interface{}) error {
 	return nil
 }
 
-func unmarshalTopLevelNode(x target, node *ast.Node) error {
+// The target return value is the target for the next top-level node. Mostly
+// unchanged, except by table and array table.
+func unmarshalTopLevelNode(x target, node *ast.Node) (target, error) {
 	switch node.Kind {
 	case ast.Table:
-		panic("TODO")
+		return scopeWithKey(x, node.Key())
 	case ast.ArrayTable:
 		panic("TODO")
 	case ast.KeyValue:
-		return unmarshalKeyValue(x, node)
+		return x, unmarshalKeyValue(x, node)
 	default:
 		panic(fmt.Errorf("this should not be a top level node type: %s", node.Kind))
 	}
 }
 
-func unmarshalKeyValue(x target, node *ast.Node) error {
-	assertNode(ast.KeyValue, node)
-
-	key := node.Key()
-
+func scopeWithKey(x target, key []ast.Node) (target, error) {
 	var err error
 	for _, n := range key {
 		x, err = scopeTarget(x, string(n.Data))
 		if err != nil {
-			return err
+			return nil, err
 		}
 	}
+	return x, nil
+}
+
+func unmarshalKeyValue(x target, node *ast.Node) error {
+	assertNode(ast.KeyValue, node)
+
+	x, err := scopeWithKey(x, node.Key())
+	if err != nil {
+		return err
+	}
 
 	return unmarshalValue(x, node.Value())
 }

internal/unmarshaler/unmarshaler_test.go

@@ -1,4 +1,4 @@
-package unmarshaler_test
+package unmarshaler
 
 import (
 	"testing"
@@ -7,7 +7,6 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/pelletier/go-toml/v2/internal/ast"
-	"github.com/pelletier/go-toml/v2/internal/unmarshaler"
 )
 
 func TestFromAst_KV(t *testing.T) {
@@ -32,11 +31,112 @@ func TestFromAst_KV(t *testing.T) {
 	}
 
 	x := Doc{}
-	err := unmarshaler.FromAst(root, &x)
+	err := fromAst(root, &x)
 	require.NoError(t, err)
 	assert.Equal(t, Doc{Foo: "hello"}, x)
 }
 
+func TestFromAst_Table(t *testing.T) {
+	t.Run("one level table on struct", func(t *testing.T) {
+		root := ast.Root{
+			ast.Node{
+				Kind: ast.Table,
+				Children: []ast.Node{
+					{Kind: ast.Key, Data: []byte(`Level1`)},
+				},
+			},
+			ast.Node{
+				Kind: ast.KeyValue,
+				Children: []ast.Node{
+					{
+						Kind: ast.Key,
+						Data: []byte(`A`),
+					},
+					{
+						Kind: ast.String,
+						Data: []byte(`hello`),
+					},
+				},
+			},
+			ast.Node{
+				Kind: ast.KeyValue,
+				Children: []ast.Node{
+					{
+						Kind: ast.Key,
+						Data: []byte(`B`),
+					},
+					{
+						Kind: ast.String,
+						Data: []byte(`world`),
+					},
+				},
+			},
+		}
+
+		type Level1 struct {
+			A string
+			B string
+		}
+
+		type Doc struct {
+			Level1 Level1
+		}
+
+		x := Doc{}
+		err := fromAst(root, &x)
+		require.NoError(t, err)
+		assert.Equal(t, Doc{
+			Level1: Level1{
+				A: "hello",
+				B: "world",
+			},
+		}, x)
+	})
+	t.Run("one level table on struct", func(t *testing.T) {
+		root := ast.Root{
+			ast.Node{
+				Kind: ast.Table,
+				Children: []ast.Node{
+					{Kind: ast.Key, Data: []byte(`A`)},
+					{Kind: ast.Key, Data: []byte(`B`)},
+				},
+			},
+			ast.Node{
+				Kind: ast.KeyValue,
+				Children: []ast.Node{
+					{
+						Kind: ast.Key,
+						Data: []byte(`C`),
+					},
+					{
+						Kind: ast.String,
+						Data: []byte(`value`),
+					},
+				},
+			},
+		}
+
+		type B struct {
+			C string
+		}
+
+		type A struct {
+			B B
+		}
+
+		type Doc struct {
+			A A
+		}
+
+		x := Doc{}
+		err := fromAst(root, &x)
+		require.NoError(t, err)
+		assert.Equal(t, Doc{
+			A: A{B: B{C: "value"}},
+		}, x)
+	})
+}
+
 func TestFromAst_Slice(t *testing.T) {
 	t.Run("slice of string", func(t *testing.T) {
 		root := ast.Root{
@@ -69,7 +169,7 @@ func TestFromAst_Slice(t *testing.T) {
 		}
 
 		x := Doc{}
-		err := unmarshaler.FromAst(root, &x)
+		err := fromAst(root, &x)
 		require.NoError(t, err)
 		assert.Equal(t, Doc{Foo: []string{"hello", "world"}}, x)
 	})
@@ -105,7 +205,7 @@ func TestFromAst_Slice(t *testing.T) {
 		}
 
 		x := Doc{}
-		err := unmarshaler.FromAst(root, &x)
+		err := fromAst(root, &x)
 		require.NoError(t, err)
 		assert.Equal(t, Doc{Foo: []interface{}{"hello", "world"}}, x)
 	})
@@ -150,7 +250,7 @@ func TestFromAst_Slice(t *testing.T) {
 		}
 
 		x := Doc{}
-		err := unmarshaler.FromAst(root, &x)
+		err := fromAst(root, &x)
 		require.NoError(t, err)
 		assert.Equal(t, Doc{Foo: []interface{}{"hello", []interface{}{"inner1", "inner2"}}}, x)
 	})