smarter checking

restore.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"path/filepath"
 
+	"go.wit.com/lib/gui/shell"
 	"go.wit.com/lib/protobuf/gitpb"
 	"go.wit.com/log"
 )
@@ -14,11 +15,26 @@ func restoreFromGoPkg(repo *gitpb.Repo) error {
 	if err != nil {
 		badExit(nil, err)
 	}
+	repo.RunVerboseOnError([]string{"rm", "-f", "go.mod", "go.sum"})
 	rver := repo.GetLastTag()
 	if rver == "" {
 		return errors.New("could not get master version")
 	}
+	goget := repo.GetGoPath() + "@" + rver
+	moddir := filepath.Join(homedir, "go/pkg/mod", repo.GetGoPath()+"@"+rver)
+	if shell.IsDir(moddir) {
+		// things are ok
+	} else {
+		return errors.New("must run go get " + goget)
+	}
+
 	modfile := filepath.Join(homedir, "go/pkg/mod", repo.GetGoPath()+"@"+rver, "go.mod")
+	if shell.Exists(modfile) {
+		// go.mod exists
+	} else {
+		// nothing to do. this repo does not have a go.mod file
+		return nil
+	}
 	log.Info("mod path should be", modfile)
 	data, err := os.ReadFile(modfile)
 	if err != nil {