refactor: git repo and relative path handling (#38522)

1. simplify "StorageRepo" code
2. simplify git.OpenRepository code
3. by the way, clean up some unused files in git test fixtures.

models/migrations/v1_12/v136.go

@@ -83,7 +83,7 @@ func AddCommitDivergenceToPulls(x db.EngineMigration) error {
 				log.Error("Missing base repo with id %d for PR ID %d", pr.BaseRepoID, pr.ID)
 				continue
 			}
-			repoStore := repo_model.StorageRepo(repo_model.RelativePath(baseRepo.OwnerName, baseRepo.Name))
+			repoStore := repo_model.CodeRepoByName(baseRepo.OwnerName, baseRepo.Name)
 			gitRefName := fmt.Sprintf("refs/pull/%d/head", pr.Index)
 			divergence, err := gitrepo.GetDivergingCommits(graceful.GetManager().HammerContext(), repoStore, pr.BaseBranch, gitRefName)
 			if err != nil {

models/migrations/v1_14/v156.go

@@ -6,24 +6,14 @@ package v1_14
 import (
 	"context"
 	"fmt"
-	"path/filepath"
 	"strings"
 
 	"gitea.dev/models/db"
+	repo_model "gitea.dev/models/repo"
 	"gitea.dev/modules/git"
 	"gitea.dev/modules/log"
-	"gitea.dev/modules/setting"
 )
 
-// Copy paste from models/repo.go because we cannot import models package
-func repoPath(userName, repoName string) string {
-	return filepath.Join(userPath(userName), strings.ToLower(repoName)+".git")
-}
-
-func userPath(userName string) string {
-	return filepath.Join(setting.RepoRootPath, strings.ToLower(userName))
-}
-
 func FixPublisherIDforTagReleases(ctx context.Context, x db.EngineMigration) error {
 	type Release struct {
 		ID          int64
@@ -108,7 +98,7 @@ func FixPublisherIDforTagReleases(ctx context.Context, x db.EngineMigration) err
 						return err
 					}
 				}
-				gitRepo, err = git.OpenRepository(repoPath(repo.OwnerName, repo.Name))
+				gitRepo, err = git.OpenRepository(repo_model.CodeRepoByName(repo.OwnerName, repo.Name))
 				if err != nil {
 					log.Error("Error whilst opening git repo for [%d]%s/%s. Error: %v", repo.ID, repo.OwnerName, repo.Name, err)
 					return err

models/migrations/v1_21/v276.go

@@ -159,12 +159,12 @@ func migratePushMirrors(x db.EngineMigration) error {
 
 func getRemoteAddress(ownerName, repoName, remoteName string) (string, error) {
 	ctx := context.Background()
-	relativePath := repo_model.RelativePath(ownerName, repoName)
-	if exist, _ := gitrepo.IsRepositoryExist(ctx, repo_model.StorageRepo(relativePath)); !exist {
+	repo := repo_model.CodeRepoByName(ownerName, repoName)
+	if exist, _ := gitrepo.IsRepositoryExist(ctx, repo); !exist {
 		return "", nil
 	}
 
-	u, err := gitrepo.GitRemoteGetURL(ctx, repo_model.StorageRepo(relativePath), remoteName)
+	u, err := gitrepo.GitRemoteGetURL(ctx, repo, remoteName)
 	if err != nil {
 		return "", err
 	}

models/migrations/v1_9/v82.go

@@ -87,7 +87,7 @@ func FixReleaseSha1OnReleaseTable(ctx context.Context, x db.EngineMigration) err
 					userCache[repo.OwnerID] = user
 				}
 
-				gitRepo, err = gitrepo.OpenRepository(repo_model.StorageRepo(repo_model.RelativePath(user.Name, repo.Name)))
+				gitRepo, err = gitrepo.OpenRepository(repo_model.CodeRepoByName(user.Name, repo.Name))
 				if err != nil {
 					return err
 				}