137 lines
3.6 KiB
Go
137 lines
3.6 KiB
Go
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 referring 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()}
|
|
}
|