Update vendor/

vendor/github.com/emersion/go-imap/imap.go

@@ -2,9 +2,60 @@
 package imap
 
 import (
+	"errors"
 	"io"
+	"strings"
 )
 
+// A StatusItem is a mailbox status data item that can be retrieved with a
+// STATUS command. See RFC 3501 section 6.3.10.
+type StatusItem string
+
+const (
+	StatusMessages    StatusItem = "MESSAGES"
+	StatusRecent                 = "RECENT"
+	StatusUidNext                = "UIDNEXT"
+	StatusUidValidity            = "UIDVALIDITY"
+	StatusUnseen                 = "UNSEEN"
+)
+
+// A FetchItem is a message data item that can be fetched.
+type FetchItem string
+
+// List of items that can be fetched.
+const (
+	// Macros
+	FetchAll  FetchItem = "ALL"
+	FetchFast           = "FAST"
+	FetchFull           = "FULL"
+
+	// Items
+	FetchBody          = "BODY"
+	FetchBodyStructure = "BODYSTRUCTURE"
+	FetchEnvelope      = "ENVELOPE"
+	FetchFlags         = "FLAGS"
+	FetchInternalDate  = "INTERNALDATE"
+	FetchRFC822        = "RFC822"
+	FetchRFC822Header  = "RFC822.HEADER"
+	FetchRFC822Size    = "RFC822.SIZE"
+	FetchRFC822Text    = "RFC822.TEXT"
+	FetchUid           = "UID"
+)
+
+// Expand expands the item if it's a macro.
+func (item FetchItem) Expand() []FetchItem {
+	switch item {
+	case FetchAll:
+		return []FetchItem{FetchFlags, FetchInternalDate, FetchRFC822Size, FetchEnvelope}
+	case FetchFast:
+		return []FetchItem{FetchFlags, FetchInternalDate, FetchRFC822Size}
+	case FetchFull:
+		return []FetchItem{FetchFlags, FetchInternalDate, FetchRFC822Size, FetchEnvelope, FetchBody}
+	default:
+		return []FetchItem{item}
+	}
+}
+
 // FlagsOp is an operation that will be applied on message flags.
 type FlagsOp string
 
@@ -17,9 +68,36 @@ const (
 	RemoveFlags = "-FLAGS"
 )
 
-// SilentOp can be appended to a FlagsOp to prevent the operation from
+// silentOp can be appended to a FlagsOp to prevent the operation from
 // triggering unilateral message updates.
-const SilentOp = ".SILENT"
+const silentOp = ".SILENT"
+
+// A StoreItem is a message data item that can be updated.
+type StoreItem string
+
+// FormatFlagsOp returns the StoreItem that executes the flags operation op.
+func FormatFlagsOp(op FlagsOp, silent bool) StoreItem {
+	s := string(op)
+	if silent {
+		s += silentOp
+	}
+	return StoreItem(s)
+}
+
+// ParseFlagsOp parses a flags operation from StoreItem.
+func ParseFlagsOp(item StoreItem) (op FlagsOp, silent bool, err error) {
+	itemStr := string(item)
+	silent = strings.HasSuffix(itemStr, silentOp)
+	if silent {
+		itemStr = strings.TrimSuffix(itemStr, silentOp)
+	}
+	op = FlagsOp(itemStr)
+
+	if op != SetFlags && op != AddFlags && op != RemoveFlags {
+		err = errors.New("Unsupported STORE operation")
+	}
+	return
+}
 
 // CharsetReader, if non-nil, defines a function to generate charset-conversion
 // readers, converting from the provided charset into UTF-8. Charsets are always