Update BurntSushi/toml

vendor/github.com/BurntSushi/toml/meta.go

@@ -0,0 +1,120 @@
+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.
+
+	mapping map[string]interface{}
+	types   map[string]tomlType
+	keys    []Key
+	decoded map[string]struct{}
+}
+
+// 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 typ, ok := md.types[Key(key).String()]; ok {
+		return typ.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) {
+			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
+}