omit slash from created dskeys, fix prefixLen discrepancy

flatfs/flatfs.go

@@ -56,9 +56,10 @@ func New(path string, prefixLen int, sync bool) (*Datastore, error) {
 var padding = strings.Repeat("_", maxPrefixLen)
 
 func (fs *Datastore) encode(key datastore.Key) (dir, file string) {
-	prefix := (key.String() + padding)[:fs.prefixLen]
+	noslash := key.String()[1:]
+	prefix := (noslash + padding)[:fs.prefixLen]
 	dir = path.Join(fs.path, prefix)
-	file = path.Join(dir, key.String()+extension)
+	file = path.Join(dir, noslash+extension)
 	return dir, file
 }
 

flatfs/flatfs_test.go

@@ -152,7 +152,7 @@ func TestStorage(t *testing.T) {
 	defer cleanup()
 
 	const prefixLen = 2
-	const prefix = "q"
+	const prefix = "qu"
 	const target = prefix + string(os.PathSeparator) + "quux.data"
 	fs, err := flatfs.New(temp, prefixLen, false)
 	if err != nil {