Extract billy (#173)

* Extract billy

Billy is a new library directly extracted from go-git. It abstract
several storages systems in a filesystem interface.

More in github.com/src-d/billy

* Fix grouping in imports block

* Update billy to v1

* Re-remove fs_implementation example

1 files changed, 0 insertions, 183 deletions

diff --git a/utils/fs/os/os.go b/utils/fs/os/os.go
deleted file mode 100644
index 5f9df67..0000000
--- a/utils/fs/os/os.go
+++ /dev/null
@@ -1,183 +0,0 @@
-package os
-
-import (
-	"io/ioutil"
-	"os"
-	"path"
-	"path/filepath"
-
-	"gopkg.in/src-d/go-git.v4/utils/fs"
-)
-
-// OS a filesystem base on the os filesystem
-type OS struct {
-	base string
-}
-
-// New returns a new OS filesystem
-func New(baseDir string) *OS {
-	return &OS{
-		base: baseDir,
-	}
-}
-
-// Create creates a file and opens it with standard permissions
-// and modes O_RDWR, O_CREATE and O_TRUNC.
-func (fs *OS) Create(filename string) (fs.File, error) {
-	return fs.OpenFile(filename, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
-}
-
-// OpenFile is equivalent to standard os.OpenFile.
-// If flag os.O_CREATE is set, all parent directories will be created.
-func (fs *OS) OpenFile(filename string, flag int, perm os.FileMode) (fs.File, error) {
-	fullpath := path.Join(fs.base, filename)
-
-	if flag&os.O_CREATE != 0 {
-		if err := fs.createDir(fullpath); err != nil {
-			return nil, err
-		}
-	}
-
-	f, err := os.OpenFile(fullpath, flag, perm)
-	if err != nil {
-		return nil, err
-	}
-
-	filename, err = filepath.Rel(fs.base, fullpath)
-	if err != nil {
-		return nil, err
-	}
-
-	return newOSFile(filename, f), nil
-}
-
-func (fs *OS) createDir(fullpath string) error {
-	dir := filepath.Dir(fullpath)
-	if dir != "." {
-		if err := os.MkdirAll(dir, 0755); err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
-// ReadDir returns the filesystem info for all the archives under the specified
-// path.
-func (ofs *OS) ReadDir(path string) ([]fs.FileInfo, error) {
-	fullpath := ofs.Join(ofs.base, path)
-
-	l, err := ioutil.ReadDir(fullpath)
-	if err != nil {
-		return nil, err
-	}
-
-	var s = make([]fs.FileInfo, len(l))
-	for i, f := range l {
-		s[i] = f
-	}
-
-	return s, nil
-}
-
-func (fs *OS) Rename(from, to string) error {
-	from = fs.Join(fs.base, from)
-	to = fs.Join(fs.base, to)
-
-	if err := fs.createDir(to); err != nil {
-		return err
-	}
-
-	return os.Rename(from, to)
-}
-
-// Open opens a file in read-only mode.
-func (fs *OS) Open(filename string) (fs.File, error) {
-	return fs.OpenFile(filename, os.O_RDONLY, 0)
-}
-
-// Stat returns the FileInfo structure describing file.
-func (fs *OS) Stat(filename string) (fs.FileInfo, error) {
-	fullpath := fs.Join(fs.base, filename)
-	return os.Stat(fullpath)
-}
-
-func (fs *OS) Remove(filename string) error {
-	fullpath := fs.Join(fs.base, filename)
-	return os.Remove(fullpath)
-}
-
-func (fs *OS) TempFile(dir, prefix string) (fs.File, error) {
-	fullpath := fs.Join(fs.base, dir)
-	if err := fs.createDir(fullpath + string(os.PathSeparator)); err != nil {
-		return nil, err
-	}
-
-	f, err := ioutil.TempFile(fullpath, prefix)
-	if err != nil {
-		return nil, err
-	}
-
-	s, err := f.Stat()
-	if err != nil {
-		return nil, err
-	}
-
-	filename, err := filepath.Rel(fs.base, fs.Join(fullpath, s.Name()))
-	if err != nil {
-		return nil, err
-	}
-
-	return newOSFile(filename, f), nil
-}
-
-// Join joins the specified elements using the filesystem separator.
-func (fs *OS) Join(elem ...string) string {
-	return filepath.Join(elem...)
-}
-
-// Dir returns a new Filesystem from the same type of fs using as baseDir the
-// given path
-func (fs *OS) Dir(path string) fs.Filesystem {
-	return New(fs.Join(fs.base, path))
-}
-
-// Base returns the base path of the filesytem
-func (fs *OS) Base() string {
-	return fs.base
-}
-
-// osFile represents a file in the os filesystem
-type osFile struct {
-	fs.BaseFile
-	file *os.File
-}
-
-func newOSFile(filename string, file *os.File) fs.File {
-	return &osFile{
-		BaseFile: fs.BaseFile{BaseFilename: filename},
-		file:     file,
-	}
-}
-
-func (f *osFile) Read(p []byte) (int, error) {
-	return f.file.Read(p)
-}
-
-func (f *osFile) Seek(offset int64, whence int) (int64, error) {
-	return f.file.Seek(offset, whence)
-}
-
-func (f *osFile) Write(p []byte) (int, error) {
-	return f.file.Write(p)
-}
-
-func (f *osFile) Close() error {
-	f.BaseFile.Closed = true
-
-	return f.file.Close()
-}
-
-func (f *osFile) ReadAt(p []byte, off int64) (int, error) {
-	return f.file.ReadAt(p, off)
-}