Update dependencies (#1951)

vendor/github.com/pelletier/go-toml/v2/unstable/ast.go

@@ -0,0 +1,136 @@
+package unstable
+
+import (
+	"fmt"
+	"unsafe"
+
+	"github.com/pelletier/go-toml/v2/internal/danger"
+)
+
+// Iterator over a sequence of nodes.
+//
+// Starts uninitialized, you need to call Next() first.
+//
+// For example:
+//
+//	it := n.Children()
+//	for it.Next() {
+//		n := it.Node()
+//		// do something with n
+//	}
+type Iterator struct {
+	started bool
+	node    *Node
+}
+
+// Next moves the iterator forward and returns true if points to a
+// node, false otherwise.
+func (c *Iterator) Next() bool {
+	if !c.started {
+		c.started = true
+	} else if c.node.Valid() {
+		c.node = c.node.Next()
+	}
+	return c.node.Valid()
+}
+
+// IsLast returns true if the current node of the iterator is the last
+// one.  Subsequent calls to Next() will return false.
+func (c *Iterator) IsLast() bool {
+	return c.node.next == 0
+}
+
+// Node returns a pointer to the node pointed at by the iterator.
+func (c *Iterator) Node() *Node {
+	return c.node
+}
+
+// Node in a TOML expression AST.
+//
+// Depending on Kind, its sequence of children should be interpreted
+// differently.
+//
+//   - Array have one child per element in the array.
+//   - InlineTable have one child per key-value in the table (each of kind
+//     InlineTable).
+//   - KeyValue have at least two children. The first one is the value. The rest
+//     make a potentially dotted key.
+//   - Table and ArrayTable's children represent a dotted key (same as
+//     KeyValue, but without the first node being the value).
+//
+// When relevant, Raw describes the range of bytes this node is refering to in
+// the input document. Use Parser.Raw() to retrieve the actual bytes.
+type Node struct {
+	Kind Kind
+	Raw  Range  // Raw bytes from the input.
+	Data []byte // Node value (either allocated or referencing the input).
+
+	// References to other nodes, as offsets in the backing array
+	// from this node. References can go backward, so those can be
+	// negative.
+	next  int // 0 if last element
+	child int // 0 if no child
+}
+
+// Range of bytes in the document.
+type Range struct {
+	Offset uint32
+	Length uint32
+}
+
+// Next returns a pointer to the next node, or nil if there is no next node.
+func (n *Node) Next() *Node {
+	if n.next == 0 {
+		return nil
+	}
+	ptr := unsafe.Pointer(n)
+	size := unsafe.Sizeof(Node{})
+	return (*Node)(danger.Stride(ptr, size, n.next))
+}
+
+// Child returns a pointer to the first child node of this node. Other children
+// can be accessed calling Next on the first child.  Returns an nil if this Node
+// has no child.
+func (n *Node) Child() *Node {
+	if n.child == 0 {
+		return nil
+	}
+	ptr := unsafe.Pointer(n)
+	size := unsafe.Sizeof(Node{})
+	return (*Node)(danger.Stride(ptr, size, n.child))
+}
+
+// Valid returns true if the node's kind is set (not to Invalid).
+func (n *Node) Valid() bool {
+	return n != nil
+}
+
+// Key returns the children 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.
+func (n *Node) Key() Iterator {
+	switch n.Kind {
+	case KeyValue:
+		value := n.Child()
+		if !value.Valid() {
+			panic(fmt.Errorf("KeyValue should have at least two children"))
+		}
+		return Iterator{node: value.Next()}
+	case Table, ArrayTable:
+		return Iterator{node: n.Child()}
+	default:
+		panic(fmt.Errorf("Key() is not supported on a %s", n.Kind))
+	}
+}
+
+// Value returns a pointer to the value node of a KeyValue.
+// Guaranteed to be non-nil.  Panics if not called on a KeyValue node,
+// or if the Children are malformed.
+func (n *Node) Value() *Node {
+	return n.Child()
+}
+
+// Children returns an iterator over a node's children.
+func (n *Node) Children() Iterator {
+	return Iterator{node: n.Child()}
+}