files2.0: address review

License: MIT
Signed-off-by: Łukasz Magiera <magik6k@gmail.com>

cmd/ipfs/init.go

@@ -87,15 +87,19 @@ environment variable:
 		f := req.Files
 		if f != nil {
 			it := req.Files.Entries()
-			if !it.Next() && it.Err() != nil {
+			if !it.Next() {
+				if it.Err() != nil {
 					return it.Err()
 				}
-			if files.FileFromEntry(it) == nil {
+				return fmt.Errorf("file argument was nil")
+			}
+			file := files.FileFromEntry(it)
+			if file == nil {
 				return fmt.Errorf("expected a regular file")
 			}
 
 			conf = &config.Config{}
-			if err := json.NewDecoder(files.FileFromEntry(it)).Decode(conf); err != nil {
+			if err := json.NewDecoder(file).Decode(conf); err != nil {
 				return err
 			}
 		}

core/commands/cat.go

@@ -130,7 +130,7 @@ func cat(ctx context.Context, api iface.CoreAPI, paths []string, offset int64, m
 
 		file, ok := f.(files.File)
 		if !ok {
-			return nil, 0, iface.ErrIsDir
+			return nil, 0, iface.ErrNotFile
 		}
 
 		fsize, err := file.Size()

core/commands/cmdenv/file.go

@@ -6,6 +6,7 @@ import (
 	files "gx/ipfs/QmXWZCd8jfaHmt4UDSnjKmGcrQMw95bDGWqEeVLVJjoANX/go-ipfs-files"
 )
 
+// GetFileArg returns the next file from the directory or an error
 func GetFileArg(it files.DirIterator) (files.File, error) {
 	if !it.Next() {
 		err := it.Err()

core/coreapi/interface/errors.go

@@ -4,5 +4,6 @@ import "errors"
 
 var (
 	ErrIsDir   = errors.New("this dag node is a directory")
+	ErrNotFile = errors.New("this dag node is not a regular file")
 	ErrOffline = errors.New("this action must be run in online mode, try running 'ipfs daemon' first")
 )