more UI and change default local user permissions

app_test.go

@@ -1,6 +1,9 @@
 package main
 
-import "testing"
+import (
+	"os/user"
+	"testing"
+)
 
 func TestParseCIFSMountEntries(t *testing.T) {
 	contents := `# comment
@@ -86,3 +89,56 @@ func TestUpdateFstabContentsAddEditDelete(t *testing.T) {
 		t.Fatalf("unexpected delete result:\nwant: %q\ngot:  %q", wantDeleted, deleted)
 	}
 }
+
+func TestDefaultLocalMountOwnerGroupUsesCurrentUser(t *testing.T) {
+	getenv := func(string) string { return "" }
+	currentUser := func() (*user.User, error) {
+		return &user.User{Username: "alice", Gid: "1000"}, nil
+	}
+	lookupUser := func(string) (*user.User, error) {
+		t.Fatal("lookupUser should not be called without SUDO_USER")
+		return nil, nil
+	}
+	lookupGroupID := func(id string) (*user.Group, error) {
+		if id != "1000" {
+			t.Fatalf("unexpected group id lookup: %q", id)
+		}
+		return &user.Group{Name: "alice"}, nil
+	}
+
+	uid, gid := defaultLocalMountOwnerGroup(getenv, currentUser, lookupUser, lookupGroupID)
+	if uid != "alice" || gid != "alice" {
+		t.Fatalf("unexpected defaults: uid=%q gid=%q", uid, gid)
+	}
+}
+
+func TestDefaultLocalMountOwnerGroupUsesSudoUser(t *testing.T) {
+	getenv := func(key string) string {
+		switch key {
+		case "SUDO_USER":
+			return "carol"
+		case "SUDO_GID":
+			return "2000"
+		default:
+			return ""
+		}
+	}
+	currentUser := func() (*user.User, error) {
+		return &user.User{Username: "root", Gid: "0"}, nil
+	}
+	lookupUser := func(string) (*user.User, error) {
+		t.Fatal("lookupUser should not be called when SUDO_GID is set")
+		return nil, nil
+	}
+	lookupGroupID := func(id string) (*user.Group, error) {
+		if id != "2000" {
+			t.Fatalf("unexpected group id lookup: %q", id)
+		}
+		return &user.Group{Name: "developers"}, nil
+	}
+
+	uid, gid := defaultLocalMountOwnerGroup(getenv, currentUser, lookupUser, lookupGroupID)
+	if uid != "carol" || gid != "developers" {
+		t.Fatalf("unexpected defaults: uid=%q gid=%q", uid, gid)
+	}
+}