github.com/switchupcb/yaegi@v0.10.2/_test/issue-558.go (about)

     1  package main
     2  
     3  import (
     4  	"fmt"
     5  	"io"
     6  	"io/ioutil"
     7  	"log"
     8  	"strings"
     9  )
    10  
    11  type readAutoCloser struct {
    12  	r io.ReadCloser
    13  }
    14  
    15  func (a readAutoCloser) Read(b []byte) (n int, err error) {
    16  	if a.r == nil {
    17  		return 0, io.EOF
    18  	}
    19  	n, err = a.r.Read(b)
    20  	if err == io.EOF {
    21  		a.Close()
    22  	}
    23  	return n, err
    24  }
    25  
    26  func (a readAutoCloser) Close() error {
    27  	if a.r == nil {
    28  		return nil
    29  	}
    30  	return a.r.(io.Closer).Close()
    31  }
    32  
    33  type pipe struct {
    34  	Reader readAutoCloser
    35  }
    36  
    37  func newReadAutoCloser(r io.Reader) readAutoCloser {
    38  	if _, ok := r.(io.Closer); !ok {
    39  		return readAutoCloser{ioutil.NopCloser(r)}
    40  	}
    41  	return readAutoCloser{r.(io.ReadCloser)}
    42  }
    43  
    44  func main() {
    45  	p := &pipe{}
    46  	p.Reader = newReadAutoCloser(strings.NewReader("test"))
    47  	b, err := ioutil.ReadAll(p.Reader)
    48  	if err != nil {
    49  		log.Fatal(err)
    50  	}
    51  	fmt.Println(string(b))
    52  }
    53  
    54  // Output:
    55  // test