Fix TestUserCreateBranch_successful writing into shared repository

TestUserCreateBranch_successful is setting up a shared repository in
the tests. It then proceeds to concurrently write to the shared
repository in the subtests. This leads to indeterministic results as
the branch may or may not be already created by one of the other
subtests. Fix this by running each of the tests agains their own
repository. As all tests are now running agains their own repositories,
we know longer need to delete the created branch at the end of the test.

1 files changed, 52 insertions, 37 deletions

diff --git a/internal/gitaly/service/operations/user_create_branch_test.go b/internal/gitaly/service/operations/user_create_branch_test.go
index 964ab5239..11c3f4926 100644
--- a/internal/gitaly/service/operations/user_create_branch_test.go
+++ b/internal/gitaly/service/operations/user_create_branch_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
+	"gitlab.com/gitlab-org/gitaly/v16/internal/git"
 	"gitlab.com/gitlab-org/gitaly/v16/internal/git/gittest"
 	"gitlab.com/gitlab-org/gitaly/v16/internal/git/localrepo"
 	"gitlab.com/gitlab-org/gitaly/v16/internal/gitaly/service"
@@ -28,29 +29,27 @@ func TestUserCreateBranch_successful(t *testing.T) {
 	ctx := testhelper.Context(t)
 	ctx, cfg, client := setupOperationsService(t, ctx)
 
-	repo, repoPath := gittest.CreateRepository(t, ctx, cfg)
-
-	startPoint := gittest.WriteCommit(t, cfg, repoPath, gittest.WithTreeEntries(
-		gittest.TreeEntry{Mode: "100644", Path: "foo", Content: "bar"},
-	))
-
-	localRepo := localrepo.NewTestRepo(t, cfg, repo)
-	startPointCommit, err := localRepo.ReadCommit(ctx, startPoint.Revision())
-	require.NoError(t, err)
-
-	testCases := []struct {
-		desc           string
+	type setupData struct {
 		branchName     string
 		startPoint     string
 		expectedBranch *gitalypb.Branch
+	}
+
+	testCases := []struct {
+		desc  string
+		setup func(git.ObjectID, *gitalypb.GitCommit) setupData
 	}{
 		{
-			desc:       "valid branch",
-			branchName: "new-branch",
-			startPoint: startPoint.String(),
-			expectedBranch: &gitalypb.Branch{
-				Name:         []byte("new-branch"),
-				TargetCommit: startPointCommit,
+			desc: "valid branch",
+			setup: func(startPoint git.ObjectID, startPointCommit *gitalypb.GitCommit) setupData {
+				return setupData{
+					branchName: "new-branch",
+					startPoint: startPoint.String(),
+					expectedBranch: &gitalypb.Branch{
+						Name:         []byte("new-branch"),
+						TargetCommit: startPointCommit,
+					},
+				}
 			},
 		},
 		// On input like heads/foo and refs/heads/foo we don't
@@ -59,21 +58,29 @@ func TestUserCreateBranch_successful(t *testing.T) {
 		// prepend refs/heads/*, so you get
 		// refs/heads/heads/foo and refs/heads/refs/heads/foo
 		{
-			desc:       "valid branch",
-			branchName: "heads/new-branch",
-			startPoint: startPoint.String(),
-			expectedBranch: &gitalypb.Branch{
-				Name:         []byte("heads/new-branch"),
-				TargetCommit: startPointCommit,
+			desc: "valid branch",
+			setup: func(startPoint git.ObjectID, startPointCommit *gitalypb.GitCommit) setupData {
+				return setupData{
+					branchName: "heads/new-branch",
+					startPoint: startPoint.String(),
+					expectedBranch: &gitalypb.Branch{
+						Name:         []byte("heads/new-branch"),
+						TargetCommit: startPointCommit,
+					},
+				}
 			},
 		},
 		{
-			desc:       "valid branch",
-			branchName: "refs/heads/new-branch",
-			startPoint: startPoint.String(),
-			expectedBranch: &gitalypb.Branch{
-				Name:         []byte("refs/heads/new-branch"),
-				TargetCommit: startPointCommit,
+			desc: "valid branch",
+			setup: func(startPoint git.ObjectID, startPointCommit *gitalypb.GitCommit) setupData {
+				return setupData{
+					branchName: "refs/heads/new-branch",
+					startPoint: startPoint.String(),
+					expectedBranch: &gitalypb.Branch{
+						Name:         []byte("refs/heads/new-branch"),
+						TargetCommit: startPointCommit,
+					},
+				}
 			},
 		},
 	}
@@ -84,21 +91,29 @@ func TestUserCreateBranch_successful(t *testing.T) {
 		t.Run(tc.desc, func(t *testing.T) {
 			t.Parallel()
 
-			branchName := tc.branchName
+			repo, repoPath := gittest.CreateRepository(t, ctx, cfg)
+
+			startPoint := gittest.WriteCommit(t, cfg, repoPath, gittest.WithTreeEntries(
+				gittest.TreeEntry{Mode: "100644", Path: "foo", Content: "bar"},
+			))
+
+			localRepo := localrepo.NewTestRepo(t, cfg, repo)
+			startPointCommit, err := localRepo.ReadCommit(ctx, startPoint.Revision())
+			require.NoError(t, err)
+
+			setup := tc.setup(startPoint, startPointCommit)
+
+			branchName := setup.branchName
 			request := &gitalypb.UserCreateBranchRequest{
 				Repository: repo,
 				BranchName: []byte(branchName),
-				StartPoint: []byte(tc.startPoint),
+				StartPoint: []byte(setup.startPoint),
 				User:       gittest.TestUser,
 			}
 
 			response, err := client.UserCreateBranch(ctx, request)
-			if tc.expectedBranch != nil {
-				defer gittest.Exec(t, cfg, "-C", repoPath, "branch", "-D", branchName)
-			}
-
 			require.NoError(t, err)
-			require.Equal(t, tc.expectedBranch, response.Branch)
+			require.Equal(t, setup.expectedBranch, response.Branch)
 
 			branches := gittest.Exec(t, cfg, "-C", repoPath, "for-each-ref", "--", "refs/heads/"+branchName)
 			require.Contains(t, string(branches), "refs/heads/"+branchName)