dnscrypt-proxy/vendor/github.com/BurntSushi/toml/meta.go

122 lines
3.1 KiB
Go

package toml
import (
"strings"
)
// MetaData allows access to meta information about TOML data that's not
// accessible otherwise.
//
// It allows checking if a key is defined in the TOML data, whether any keys
// were undecoded, and the TOML type of a key.
type MetaData struct {
context Key // Used only during decoding.
keyInfo map[string]keyInfo
mapping map[string]interface{}
keys []Key
decoded map[string]struct{}
data []byte // Input file; for errors.
}
// IsDefined reports if the key exists in the TOML data.
//
// The key should be specified hierarchically, for example to access the TOML
// key "a.b.c" you would use IsDefined("a", "b", "c"). Keys are case sensitive.
//
// Returns false for an empty key.
func (md *MetaData) IsDefined(key ...string) bool {
if len(key) == 0 {
return false
}
var (
hash map[string]interface{}
ok bool
hashOrVal interface{} = md.mapping
)
for _, k := range key {
if hash, ok = hashOrVal.(map[string]interface{}); !ok {
return false
}
if hashOrVal, ok = hash[k]; !ok {
return false
}
}
return true
}
// Type returns a string representation of the type of the key specified.
//
// Type will return the empty string if given an empty key or a key that does
// not exist. Keys are case sensitive.
func (md *MetaData) Type(key ...string) string {
if ki, ok := md.keyInfo[Key(key).String()]; ok {
return ki.tomlType.typeString()
}
return ""
}
// Keys returns a slice of every key in the TOML data, including key groups.
//
// Each key is itself a slice, where the first element is the top of the
// hierarchy and the last is the most specific. The list will have the same
// order as the keys appeared in the TOML data.
//
// All keys returned are non-empty.
func (md *MetaData) Keys() []Key {
return md.keys
}
// Undecoded returns all keys that have not been decoded in the order in which
// they appear in the original TOML document.
//
// This includes keys that haven't been decoded because of a [Primitive] value.
// Once the Primitive value is decoded, the keys will be considered decoded.
//
// Also note that decoding into an empty interface will result in no decoding,
// and so no keys will be considered decoded.
//
// In this sense, the Undecoded keys correspond to keys in the TOML document
// that do not have a concrete type in your representation.
func (md *MetaData) Undecoded() []Key {
undecoded := make([]Key, 0, len(md.keys))
for _, key := range md.keys {
if _, ok := md.decoded[key.String()]; !ok {
undecoded = append(undecoded, key)
}
}
return undecoded
}
// Key represents any TOML key, including key groups. Use [MetaData.Keys] to get
// values of this type.
type Key []string
func (k Key) String() string {
ss := make([]string, len(k))
for i := range k {
ss[i] = k.maybeQuoted(i)
}
return strings.Join(ss, ".")
}
func (k Key) maybeQuoted(i int) string {
if k[i] == "" {
return `""`
}
for _, c := range k[i] {
if !isBareKeyChar(c, false) {
return `"` + dblQuotedReplacer.Replace(k[i]) + `"`
}
}
return k[i]
}
func (k Key) add(piece string) Key {
newKey := make(Key, len(k)+1)
copy(newKey, k)
newKey[len(k)] = piece
return newKey
}