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package test
import "io"
// PlainReader implements an io.Reader and wraps over an existing io.Reader to hide other functions it implements.
type PlainReader struct {
r io.Reader
}
// NewPlainReader returns a new PlainReader.
func NewPlainReader(r io.Reader) *PlainReader {
return &PlainReader{r}
}
// Read implements the io.Reader interface.
func (r *PlainReader) Read(p []byte) (int, error) {
return r.r.Read(p)
}
////////////////////////////////////////////////////////////////
// ErrorReader implements an io.Reader that will do N successive reads before it returns ErrPlain.
type ErrorReader struct {
n int
}
// NewErrorReader returns a new ErrorReader.
func NewErrorReader(n int) *ErrorReader {
return &ErrorReader{n}
}
// Read implements the io.Reader interface.
func (r *ErrorReader) Read(b []byte) (n int, err error) {
if len(b) == 0 {
return 0, nil
}
if r.n == 0 {
return 0, ErrPlain
}
r.n--
b[0] = '.'
return 1, nil
}
////////////////////////////////////////////////////////////////
// InfiniteReader implements an io.Reader that will always read-in one character.
type InfiniteReader struct{}
// NewInfiniteReader returns a new InfiniteReader.
func NewInfiniteReader() *InfiniteReader {
return &InfiniteReader{}
}
// Read implements the io.Reader interface.
func (r *InfiniteReader) Read(b []byte) (n int, err error) {
if len(b) == 0 {
return 0, nil
}
b[0] = '.'
return 1, nil
}
////////////////////////////////////////////////////////////////
// EmptyReader implements an io.Reader that will always return 0, nil.
type EmptyReader struct {
}
// NewEmptyReader returns a new EmptyReader.
func NewEmptyReader() *EmptyReader {
return &EmptyReader{}
}
// Read implements the io.Reader interface.
func (r *EmptyReader) Read(b []byte) (n int, err error) {
return 0, io.EOF
}
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