github.com/ssdev-go/moby@v17.12.1-ce-rc2+incompatible/pkg/ioutils/readers_test.go (about)

     1  package ioutils
     2  
     3  import (
     4  	"fmt"
     5  	"io/ioutil"
     6  	"strings"
     7  	"testing"
     8  	"time"
     9  
    10  	"github.com/stretchr/testify/assert"
    11  	"golang.org/x/net/context"
    12  )
    13  
    14  // Implement io.Reader
    15  type errorReader struct{}
    16  
    17  func (r *errorReader) Read(p []byte) (int, error) {
    18  	return 0, fmt.Errorf("error reader always fail")
    19  }
    20  
    21  func TestReadCloserWrapperClose(t *testing.T) {
    22  	reader := strings.NewReader("A string reader")
    23  	wrapper := NewReadCloserWrapper(reader, func() error {
    24  		return fmt.Errorf("This will be called when closing")
    25  	})
    26  	err := wrapper.Close()
    27  	if err == nil || !strings.Contains(err.Error(), "This will be called when closing") {
    28  		t.Fatalf("readCloserWrapper should have call the anonymous func and thus, fail.")
    29  	}
    30  }
    31  
    32  func TestReaderErrWrapperReadOnError(t *testing.T) {
    33  	called := false
    34  	reader := &errorReader{}
    35  	wrapper := NewReaderErrWrapper(reader, func() {
    36  		called = true
    37  	})
    38  	_, err := wrapper.Read([]byte{})
    39  	assert.EqualError(t, err, "error reader always fail")
    40  	if !called {
    41  		t.Fatalf("readErrWrapper should have call the anonymous function on failure")
    42  	}
    43  }
    44  
    45  func TestReaderErrWrapperRead(t *testing.T) {
    46  	reader := strings.NewReader("a string reader.")
    47  	wrapper := NewReaderErrWrapper(reader, func() {
    48  		t.Fatalf("readErrWrapper should not have called the anonymous function")
    49  	})
    50  	// Read 20 byte (should be ok with the string above)
    51  	num, err := wrapper.Read(make([]byte, 20))
    52  	if err != nil {
    53  		t.Fatal(err)
    54  	}
    55  	if num != 16 {
    56  		t.Fatalf("readerErrWrapper should have read 16 byte, but read %d", num)
    57  	}
    58  }
    59  
    60  func TestHashData(t *testing.T) {
    61  	reader := strings.NewReader("hash-me")
    62  	actual, err := HashData(reader)
    63  	if err != nil {
    64  		t.Fatal(err)
    65  	}
    66  	expected := "sha256:4d11186aed035cc624d553e10db358492c84a7cd6b9670d92123c144930450aa"
    67  	if actual != expected {
    68  		t.Fatalf("Expecting %s, got %s", expected, actual)
    69  	}
    70  }
    71  
    72  type perpetualReader struct{}
    73  
    74  func (p *perpetualReader) Read(buf []byte) (n int, err error) {
    75  	for i := 0; i != len(buf); i++ {
    76  		buf[i] = 'a'
    77  	}
    78  	return len(buf), nil
    79  }
    80  
    81  func TestCancelReadCloser(t *testing.T) {
    82  	ctx, _ := context.WithTimeout(context.Background(), 100*time.Millisecond)
    83  	cancelReadCloser := NewCancelReadCloser(ctx, ioutil.NopCloser(&perpetualReader{}))
    84  	for {
    85  		var buf [128]byte
    86  		_, err := cancelReadCloser.Read(buf[:])
    87  		if err == context.DeadlineExceeded {
    88  			break
    89  		} else if err != nil {
    90  			t.Fatalf("got unexpected error: %v", err)
    91  		}
    92  	}
    93  }