GoToSocial/vendor/github.com/ncruces/go-strftime/parser.go

108 lines
1.8 KiB
Go

package strftime
import "unicode/utf8"
type parser struct {
format func(spec, flag byte) error
literal func(byte) error
}
func (p *parser) parse(fmt string) error {
const (
initial = iota
percent
flagged
modified
)
var flag, modifier byte
var err error
state := initial
start := 0
for i, b := range []byte(fmt) {
switch state {
default:
if b == '%' {
state = percent
start = i
continue
}
err = p.literal(b)
case percent:
if b == '-' || b == ':' {
state = flagged
flag = b
continue
}
if b == 'E' || b == 'O' {
state = modified
modifier = b
flag = 0
continue
}
err = p.format(b, 0)
state = initial
case flagged:
if b == 'E' || b == 'O' {
state = modified
modifier = b
continue
}
err = p.format(b, flag)
state = initial
case modified:
if okModifier(modifier, b) {
err = p.format(b, flag)
} else {
err = p.literals(fmt[start : i+1])
}
state = initial
}
if err != nil {
if err, ok := err.(formatError); ok {
err.setDirective(fmt, start, i)
return err
}
return err
}
}
if state != initial {
return p.literals(fmt[start:])
}
return nil
}
func (p *parser) literals(literal string) error {
for _, b := range []byte(literal) {
if err := p.literal(b); err != nil {
return err
}
}
return nil
}
type literalErr string
func (e literalErr) Error() string {
return "strftime: unsupported literal: " + string(e)
}
type formatError struct {
message string
directive string
}
func (e formatError) Error() string {
return "strftime: unsupported directive: " + e.directive + " " + e.message
}
func (e *formatError) setDirective(str string, i, j int) {
_, n := utf8.DecodeRuneInString(str[j:])
e.directive = str[i : j+n]
}