ipld-eth-server/vendor/github.com/dave/jennifer/jen/statement.go

102 lines
2.1 KiB
Go

package jen
import (
"bytes"
"fmt"
"go/format"
"io"
)
// Statement represents a simple list of code items. When rendered the items
// are separated by spaces.
type Statement []Code
func newStatement() *Statement {
return &Statement{}
}
// Clone makes a copy of the Statement, so further tokens can be appended
// without affecting the original.
func (s *Statement) Clone() *Statement {
return &Statement{s}
}
func (s *Statement) previous(c Code) Code {
index := -1
for i, item := range *s {
if item == c {
index = i
break
}
}
if index > 0 {
return (*s)[index-1]
}
return nil
}
func (s *Statement) isNull(f *File) bool {
if s == nil {
return true
}
for _, c := range *s {
if !c.isNull(f) {
return false
}
}
return true
}
func (s *Statement) render(f *File, w io.Writer, _ *Statement) error {
first := true
for _, code := range *s {
if code == nil || code.isNull(f) {
// Null() token produces no output but also
// no separator. Empty() token products no
// output but adds a separator.
continue
}
if !first {
if _, err := w.Write([]byte(" ")); err != nil {
return err
}
}
if err := code.render(f, w, s); err != nil {
return err
}
first = false
}
return nil
}
// Render renders the Statement to the provided writer.
func (s *Statement) Render(writer io.Writer) error {
return s.RenderWithFile(writer, NewFile(""))
}
// GoString renders the Statement for testing. Any error will cause a panic.
func (s *Statement) GoString() string {
buf := bytes.Buffer{}
if err := s.Render(&buf); err != nil {
panic(err)
}
return buf.String()
}
// RenderWithFile renders the Statement to the provided writer, using imports from the provided file.
func (s *Statement) RenderWithFile(writer io.Writer, file *File) error {
buf := &bytes.Buffer{}
if err := s.render(file, buf, nil); err != nil {
return err
}
b, err := format.Source(buf.Bytes())
if err != nil {
return fmt.Errorf("Error %s while formatting source:\n%s", err, buf.String())
}
if _, err := writer.Write(b); err != nil {
return err
}
return nil
}