go-common/app/tool/gengo/generator/error_tracker.go
2019-04-22 18:49:16 +08:00

35 lines
730 B
Go

package generator
import (
"io"
)
// ErrorTracker tracks errors to the underlying writer, so that you can ignore
// them until you're ready to return.
type ErrorTracker struct {
io.Writer
err error
}
// NewErrorTracker makes a new error tracker; note that it implements io.Writer.
func NewErrorTracker(w io.Writer) *ErrorTracker {
return &ErrorTracker{Writer: w}
}
// Write intercepts calls to Write.
func (et *ErrorTracker) Write(p []byte) (n int, err error) {
if et.err != nil {
return 0, et.err
}
n, err = et.Writer.Write(p)
if err != nil {
et.err = err
}
return n, err
}
// Error returns nil if no error has occurred, otherwise it returns the error.
func (et *ErrorTracker) Error() error {
return et.err
}