Error checkout if repository is dirty

Under certain circumstances, go-git can fail to complete checkout, while not even returning an error. While the clean and hard reset processes should ensure this is corrected, the fact that it is necessary casts doubt on the reliability of go-git.

It's very important that the releases distributed by Library Manager match the repository, so it's better to reject any releases that can't be brought into a clean state.

Author: per1234

internal/libraries/gitutils/gitutils.go

@@ -24,6 +24,7 @@
 package gitutils
 
 import (
+	"fmt"
 	"sort"
 
 	"github.com/go-git/go-git/v5"
@@ -189,5 +190,13 @@ func CheckoutTag(repository *git.Repository, tag *plumbing.Reference) error {
 		return err
 	}
 
+	repoStatus, err := repoTree.Status()
+	if err != nil {
+		return err
+	}
+	if !repoStatus.IsClean() {
+		return fmt.Errorf("failed to get repository to clean state")
+	}
+
 	return nil
 }