SyncCapability is not a DefaultCapability

Author: georg

fs.go

@@ -42,7 +42,7 @@ const (
 	// major version is released.
 	DefaultCapabilities Capability = WriteCapability | ReadCapability |
 		ReadAndWriteCapability | SeekCapability | TruncateCapability |
-		LockCapability | SyncCapability
+		LockCapability
 
 	// AllCapabilities lists all capable features.
 	AllCapabilities Capability = WriteCapability | ReadCapability |
@@ -184,7 +184,7 @@ type File interface {
 
 // Syncer interface can be implemented by filesystems that support syncing.
 type Syncer interface {
-	// Commit the current contents of the file to stable storage.
+	// Sync commits the current contents of the file to stable storage.
 	Sync() error
 }
 

memfs/memory_test.go

@@ -31,7 +31,7 @@ func TestCapabilities(t *testing.T) {
 	assert.True(t, ok)
 
 	caps := billy.Capabilities(fs)
-	assert.Equal(t, billy.DefaultCapabilities&^billy.LockCapability&^billy.SyncCapability, caps)
+	assert.Equal(t, billy.DefaultCapabilities&^billy.LockCapability, caps)
 }
 
 func TestModTime(t *testing.T) {

osfs/os_bound.go

@@ -54,6 +54,10 @@ func newBoundOS(d string, deduplicatePath bool) billy.Filesystem {
 	return &BoundOS{baseDir: d, deduplicatePath: deduplicatePath}
 }
 
+func (fs *BoundOS) Capabilities() billy.Capability {
+	return billy.DefaultCapabilities & billy.SyncCapability
+}
+
 func (fs *BoundOS) Create(filename string) (billy.File, error) {
 	return fs.OpenFile(filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, defaultCreateMode)
 }

osfs/os_bound_test.go

@@ -32,6 +32,16 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+func TestBoundOSCapabilities(t *testing.T) {
+	dir := t.TempDir()
+	fs := newBoundOS(dir, true)
+	_, ok := fs.(billy.Capable)
+	assert.True(t, ok)
+
+	caps := billy.Capabilities(fs)
+	assert.Equal(t, billy.DefaultCapabilities&billy.SyncCapability, caps)
+}
+
 func TestOpen(t *testing.T) {
 	tests := []struct {
 		name     string

osfs/os_chroot_test.go

@@ -45,5 +45,5 @@ func TestCapabilities(t *testing.T) {
 	assert.True(t, ok)
 
 	caps := billy.Capabilities(fs)
-	assert.Equal(t, billy.AllCapabilities, caps)
+	assert.Equal(t, billy.DefaultCapabilities, caps)
 }

util/util.go

@@ -117,10 +117,7 @@ func WriteFile(fs billy.Basic, filename string, data []byte, perm fs.FileMode) (
 		err = io.ErrShortWrite
 	}
 	if sf, ok := f.(billy.Syncer); ok {
-		err = sf.Sync()
-		if err != nil {
-			return err
-		}
+		return sf.Sync()
 	}
 
 	return nil