github.com/grailbio/base@v0.0.11/file/localdev_test.go (about)

     1  //go:build !unit
     2  // +build !unit
     3  
     4  package file_test
     5  
     6  import (
     7  	"context"
     8  	"io/ioutil"
     9  	"os/exec"
    10  	"path/filepath"
    11  	"runtime"
    12  	"sync"
    13  	"testing"
    14  
    15  	"github.com/grailbio/base/file"
    16  	"github.com/grailbio/testutil"
    17  	"github.com/grailbio/testutil/assert"
    18  	"github.com/stretchr/testify/require"
    19  )
    20  
    21  // Write to /dev/stdout. This test only checks that the write succeeds.
    22  func TestStdout(t *testing.T) {
    23  	if runtime.GOOS == "darwin" {
    24  		t.Skip("This test does not consistently work on macOS")
    25  	}
    26  	ctx := context.Background()
    27  	w, err := file.Create(ctx, "/dev/stdout")
    28  	assert.Nil(t, err)
    29  	_, err = w.Writer(ctx).Write([]byte("Hello\n"))
    30  	assert.Nil(t, err)
    31  	require.NoError(t, w.Close(ctx))
    32  }
    33  
    34  // Read and write a FIFO.
    35  func TestDevice(t *testing.T) {
    36  	mkfifo, err := exec.LookPath("mkfifo")
    37  	if err != nil {
    38  		t.Skipf("mkfifo not found, skipping the test: %v", err)
    39  	}
    40  	tempDir, cleanup := testutil.TempDir(t, "", "")
    41  	defer cleanup()
    42  
    43  	fifoPath := filepath.Join(tempDir, "fifo")
    44  	require.NoError(t, exec.Command(mkfifo, fifoPath).Run())
    45  
    46  	ctx := context.Background()
    47  	wg := sync.WaitGroup{}
    48  	wg.Add(2)
    49  	go func() {
    50  		w, err := file.Create(ctx, fifoPath)
    51  		require.NoError(t, err)
    52  		_, err = w.Writer(ctx).Write([]byte("Hello\n"))
    53  		require.NoError(t, err)
    54  		require.NoError(t, w.Close(ctx))
    55  		wg.Done()
    56  	}()
    57  
    58  	var data []byte
    59  	go func() {
    60  		r, err := file.Open(ctx, fifoPath)
    61  		require.NoError(t, err)
    62  		data, err = ioutil.ReadAll(r.Reader(ctx))
    63  		require.NoError(t, err)
    64  		wg.Done()
    65  	}()
    66  	wg.Wait()
    67  	require.Equal(t, "Hello\n", string(data))
    68  }