Code maintenance: OS user abstraction interface

internal/os/user/user.go

@@ -0,0 +1,24 @@
+package user
+
+import osuser "os/user"
+
+//go:generate mockgen -destination=mock_$GOPACKAGE/$GOFILE . OSUser
+
+type OSUser interface {
+	LookupID(uid string) (*osuser.User, error)
+	Lookup(username string) (*osuser.User, error)
+}
+
+func New() OSUser {
+	return &osUser{}
+}
+
+type osUser struct{}
+
+func (u *osUser) LookupID(uid string) (*osuser.User, error) {
+	return osuser.LookupId(uid)
+}
+
+func (u *osUser) Lookup(username string) (*osuser.User, error) {
+	return osuser.Lookup(username)
+}