harold's super service

pkging/pkgtest/suite.go

@@ -250,22 +250,21 @@ func (s Suite) Test_Open_File(t *testing.T) {
 
 			body := "!" + pt.String()
 
-			f1, err := s.Create(tt.in)
+			pkgutil.WriteFile(s, tt.in, []byte(body), 0644)
+
+			f, err := s.Open(tt.in)
 			r.NoError(err)
 
-			_, err = io.Copy(f1, strings.NewReader(body))
+			r.Equal(pt.Name, f.Path().Name)
-			r.NoError(err)
+			b, err := ioutil.ReadAll(f)
-			r.NoError(f1.Close())
-
-			f2, err := s.Open(tt.in)
-			r.NoError(err)
-
-			r.Equal(pt.Name, f2.Path().Name)
-			b, err := ioutil.ReadAll(f2)
 			r.NoError(err)
 			r.Equal(body, string(b))
 
-			r.NoError(f2.Close())
+			b, err = pkgutil.ReadFile(s, tt.in)
+			r.NoError(err)
+			r.Equal(body, string(b))
+
+			r.NoError(f.Close())
 		})
 	}
 }

pkging/pkgutil/file.go

@@ -1,13 +1,43 @@
 package pkgutil
 
 import (
+	"io"
 	"io/ioutil"
+	"os"
+	"sort"
 
 	"github.com/markbates/pkger/pkging"
 )
 
+type Opener interface {
+	Open(name string) (pkging.File, error)
+}
+
+type Creator interface {
+	Create(name string) (pkging.File, error)
+}
+
+type OpenFiler interface {
+	OpenFile(name string, flag int, perm os.FileMode) (pkging.File, error)
+}
+
+// ReadDir reads the directory named by dirname and returns a list of directory entries sorted by filename.
+func ReadDir(pkg Opener, dirname string) ([]os.FileInfo, error) {
+	f, err := pkg.Open(dirname)
+	if err != nil {
+		return nil, err
+	}
+	list, err := f.Readdir(-1)
+	f.Close()
+	if err != nil {
+		return nil, err
+	}
+	sort.Slice(list, func(i, j int) bool { return list[i].Name() < list[j].Name() })
+	return list, nil
+}
+
 // ReadFile reads the file named by filename and returns the contents. A successful call returns err == nil, not err == EOF. Because ReadFile reads the whole file, it does not treat an EOF from Read as an error to be reported.
-func ReadFile(pkg pkging.Pkger, s string) ([]byte, error) {
+func ReadFile(pkg Opener, s string) ([]byte, error) {
 	f, err := pkg.Open(s)
 	if err != nil {
 		return nil, err
@@ -15,3 +45,32 @@ func ReadFile(pkg pkging.Pkger, s string) ([]byte, error) {
 	defer f.Close()
 	return ioutil.ReadAll(f)
 }
+
+// WriteFile writes data to a file named by filename. If the file does not exist, WriteFile creates it with permissions perm; otherwise WriteFile truncates it before writing.
+func WriteFile(pkg Creator, filename string, data []byte, perm os.FileMode) error {
+	var f pkging.File
+	var err error
+
+	if of, ok := pkg.(OpenFiler); ok {
+		f, err = of.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
+		if err != nil {
+			return err
+		}
+	}
+
+	if f == nil {
+		f, err = pkg.Create(filename)
+		if err != nil {
+			return err
+		}
+	}
+
+	n, err := f.Write(data)
+	if err == nil && n < len(data) {
+		err = io.ErrShortWrite
+	}
+	if err1 := f.Close(); err == nil {
+		err = err1
+	}
+	return err
+}

pkging/stdos/stdos.go

@@ -20,6 +20,18 @@ type Pkger struct {
 	current here.Info
 }
 
+func (p *Pkger) OpenFile(name string, flag int, perm os.FileMode) (pkging.File, error) {
+	name, err := p.Abs(name)
+	if err != nil {
+		return nil, err
+	}
+	f, err := os.OpenFile(name, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	return NewFile(p, f)
+}
+
 func (f *Pkger) Abs(p string) (string, error) {
 	pt, err := f.Parse(p)
 	if err != nil {