vfs: [bugfix] Implement Name() method in WriteFileHandle and ReadFileHandle

Name() method was originally left out and defaulted to the base
class which always returns empty. This trigerred incorrect behavior
in serve nfs where it relied on the Name() of the interafce to figure
out what file it was modifying.

This method is copied from RWFileHandle struct.

Added extra assert in the tests.

vfs/read.go

@@ -484,6 +484,11 @@ func (fh *ReadFileHandle) Release() error {
 	return err
 }
 
+// Name returns the name of the file from the underlying Object.
+func (fh *ReadFileHandle) Name() string {
+	return fh.file.String()
+}
+
 // Size returns the size of the underlying file
 func (fh *ReadFileHandle) Size() int64 {
 	fh.mu.Lock()

vfs/read_test.go

@@ -44,6 +44,9 @@ func TestReadFileHandleMethods(t *testing.T) {
 	assert.Equal(t, "<nil *ReadFileHandle>", (*ReadFileHandle)(nil).String())
 	assert.Equal(t, "<nil *ReadFileHandle.file>", new(ReadFileHandle).String())
 
+	// Name
+	assert.Equal(t, "dir/file1", fh.Name())
+
 	// Node
 	node := fh.Node()
 	assert.Equal(t, "file1", node.Name())

vfs/read_write_test.go

@@ -346,6 +346,9 @@ func TestRWFileHandleWriteAt(t *testing.T) {
 		return n
 	}
 
+	// Name
+	assert.Equal(t, "file1", fh.Name())
+
 	// Preconditions
 	assert.Equal(t, int64(0), offset())
 	assert.True(t, fh.opened)

vfs/write.go

@@ -322,3 +322,8 @@ func (fh *WriteFileHandle) ReadAt(p []byte, off int64) (n int, err error) {
 func (fh *WriteFileHandle) Sync() error {
 	return nil
 }
+
+// Name returns the name of the file from the underlying Object.
+func (fh *WriteFileHandle) Name() string {
+	return fh.file.String()
+}

vfs/write_test.go

@@ -39,6 +39,9 @@ func TestWriteFileHandleReadonly(t *testing.T) {
 	}
 	r, vfs, fh := writeHandleCreate(t)
 
+	// Name
+	assert.Equal(t, "file1", fh.Name())
+
 	// Write a file, so underlying remote will be created
 	_, err := fh.Write([]byte("hello"))
 	assert.NoError(t, err)