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package git
import (
"bytes"
"context"
"fmt"
"io"
"testing"
"testing/iotest"
"time"
"github.com/stretchr/testify/require"
)
type fakeReader struct {
n int
err error
}
func (f *fakeReader) Read(_ []byte) (int, error) {
return f.n, f.err
}
type fakeContextWithTimeout struct {
n int
threshold int
}
func (*fakeContextWithTimeout) Deadline() (deadline time.Time, ok bool) {
return
}
func (*fakeContextWithTimeout) Done() <-chan struct{} {
return nil
}
func (*fakeContextWithTimeout) Value(_ interface{}) interface{} {
return nil
}
func (f *fakeContextWithTimeout) Err() error {
f.n++
if f.n > f.threshold {
return context.DeadlineExceeded
}
return nil
}
func TestContextReaderRead(t *testing.T) {
underlyingReader := &fakeReader{n: 1, err: io.EOF}
for _, tc := range []struct {
desc string
ctx *fakeContextWithTimeout
expectedN int
expectedErr error
}{
{
desc: "Before and after read deadline checks are fine",
ctx: &fakeContextWithTimeout{n: 0, threshold: 2},
expectedN: underlyingReader.n,
expectedErr: underlyingReader.err,
},
{
desc: "Before read deadline check fails",
ctx: &fakeContextWithTimeout{n: 0, threshold: 0},
expectedN: 0,
expectedErr: context.DeadlineExceeded,
},
{
desc: "After read deadline check fails",
ctx: &fakeContextWithTimeout{n: 0, threshold: 1},
expectedN: underlyingReader.n,
expectedErr: context.DeadlineExceeded,
},
} {
t.Run(tc.desc, func(t *testing.T) {
cr := newContextReader(tc.ctx, underlyingReader)
n, err := cr.Read(nil)
require.Equal(t, tc.expectedN, n)
require.Equal(t, tc.expectedErr, err)
})
}
}
func TestBusyReader(t *testing.T) {
testData := "test data"
r := testReader(testData)
br, _ := newWriteAfterReader(r, &bytes.Buffer{})
result, err := io.ReadAll(br)
if err != nil {
t.Fatal(err)
}
if string(result) != testData {
t.Fatalf("expected %q, got %q", testData, result)
}
}
func TestFirstWriteAfterReadDone(t *testing.T) {
writeRecorder := &bytes.Buffer{}
br, cw := newWriteAfterReader(&bytes.Buffer{}, writeRecorder)
if _, err := io.Copy(io.Discard, br); err != nil {
t.Fatalf("copy from busyreader: %v", err)
}
testData := "test data"
if _, err := io.Copy(cw, testReader(testData)); err != nil {
t.Fatalf("copy test data: %v", err)
}
if err := cw.Flush(); err != nil {
t.Fatalf("flush error: %v", err)
}
if result := writeRecorder.String(); result != testData {
t.Fatalf("expected %q, got %q", testData, result)
}
}
func TestWriteDelay(t *testing.T) {
writeRecorder := &bytes.Buffer{}
w := &complainingWriter{Writer: writeRecorder}
br, cw := newWriteAfterReader(&bytes.Buffer{}, w)
testData1 := "1 test"
if _, err := io.Copy(cw, testReader(testData1)); err != nil {
t.Fatalf("error on first copy: %v", err)
}
// Unblock the coupled writer by draining the reader
if _, err := io.Copy(io.Discard, br); err != nil {
t.Fatalf("copy from busyreader: %v", err)
}
// Now it is no longer an error if 'w' receives a Write()
w.CheerUp()
testData2 := "2 experiment"
if _, err := io.Copy(cw, testReader(testData2)); err != nil {
t.Fatalf("error on second copy: %v", err)
}
if err := cw.Flush(); err != nil {
t.Fatalf("flush error: %v", err)
}
expected := testData1 + testData2
if result := writeRecorder.String(); result != expected {
t.Fatalf("total write: expected %q, got %q", expected, result)
}
}
func TestComplainingWriterSanity(t *testing.T) {
recorder := &bytes.Buffer{}
w := &complainingWriter{Writer: recorder}
testData := "test data"
if _, err := io.Copy(w, testReader(testData)); err == nil {
t.Error("error expected, none received")
}
w.CheerUp()
if _, err := io.Copy(w, testReader(testData)); err != nil {
t.Errorf("copy after CheerUp: %v", err)
}
if result := recorder.String(); result != testData {
t.Errorf("expected %q, got %q", testData, result)
}
}
func testReader(data string) io.Reader {
return iotest.OneByteReader(bytes.NewBuffer([]byte(data)))
}
type complainingWriter struct {
happy bool
io.Writer
}
func (comp *complainingWriter) Write(data []byte) (int, error) {
if comp.happy {
return comp.Writer.Write(data)
}
return 0, fmt.Errorf("I am unhappy about you wanting to write %q", data)
}
func (comp *complainingWriter) CheerUp() {
comp.happy = true
}
|
