bots/pr/src/main/java/org/openjdk/skara/bots/pr/PullRequestInstance.java

@@ -45,11 +45,12 @@
      PullRequestInstance(Path localRepoPath, PullRequest pr) throws IOException  {
          this.pr = pr;
          var repository = pr.repository();
  
          // Materialize the PR's target ref
-         localRepo = Repository.materialize(localRepoPath, repository.url(), pr.targetRef());
+         localRepo = Repository.materialize(localRepoPath, repository.url(),
+                                            "+" + pr.targetRef() + ":pr_prinstance_" + repository.name());
          targetHash = localRepo.fetch(repository.url(), pr.targetRef());
          headHash = localRepo.fetch(repository.url(), pr.headHash().hex());
          baseHash = localRepo.mergeBase(targetHash, headHash);
      }