Remove legacy git code (ver < 2.0), fine tune markup tests (#19930)

* clean git support for ver < 2.0

* fine tune tests for markup (which requires git module)

* remove unnecessary comments

* try to fix tests

* try test again

* use const for GitVersionRequired instead of var

* try to fix integration test

* Refactor CheckAttributeReader to make a *git.Repository version

* update document for commit signing with Gitea's internal gitconfig

* update document for commit signing with Gitea's internal gitconfig

Co-authored-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

3 files changed, 34 insertions, 75 deletions

diff --git a/services/gitdiff/gitdiff.go b/services/gitdiff/gitdiff.go
index 97daadbc67..37dc0e114d 100644
--- a/services/gitdiff/gitdiff.go
+++ b/services/gitdiff/gitdiff.go
@@ -1417,37 +1417,8 @@ func GetDiff(gitRepo *git.Repository, opts *DiffOptions, files ...string) (*Diff
 	}
 	diff.Start = opts.SkipTo
 
-	var checker *git.CheckAttributeReader
-
-	if git.CheckGitVersionAtLeast("1.7.8") == nil {
-		indexFilename, worktree, deleteTemporaryFile, err := gitRepo.ReadTreeToTemporaryIndex(opts.AfterCommitID)
-		if err == nil {
-			defer deleteTemporaryFile()
-
-			checker = &git.CheckAttributeReader{
-				Attributes: []string{"linguist-vendored", "linguist-generated", "linguist-language", "gitlab-language"},
-				Repo:       gitRepo,
-				IndexFile:  indexFilename,
-				WorkTree:   worktree,
-			}
-			ctx, cancel := context.WithCancel(gitRepo.Ctx)
-			if err := checker.Init(ctx); err != nil {
-				log.Error("Unable to open checker for %s. Error: %v", opts.AfterCommitID, err)
-			} else {
-				go func() {
-					err := checker.Run()
-					if err != nil && err != ctx.Err() {
-						log.Error("Unable to open checker for %s. Error: %v", opts.AfterCommitID, err)
-					}
-					cancel()
-				}()
-			}
-			defer func() {
-				_ = checker.Close()
-				cancel()
-			}()
-		}
-	}
+	checker, deferable := gitRepo.CheckAttributeReader(opts.AfterCommitID)
+	defer deferable()
 
 	for _, diffFile := range diff.Files {
 
diff --git a/services/pull/merge.go b/services/pull/merge.go
index aff800a1b6..e8bb3a1cdd 100644
--- a/services/pull/merge.go
+++ b/services/pull/merge.go
@@ -276,15 +276,8 @@ func rawMerge(ctx context.Context, pr *issues_model.PullRequest, doer *user_mode
 		return "", fmt.Errorf("Unable to write .git/info/sparse-checkout file in tmpBasePath: %v", err)
 	}
 
-	var gitConfigCommand func() *git.Command
-	if git.CheckGitVersionAtLeast("1.8.0") == nil {
-		gitConfigCommand = func() *git.Command {
-			return git.NewCommand(ctx, "config", "--local")
-		}
-	} else {
-		gitConfigCommand = func() *git.Command {
-			return git.NewCommand(ctx, "config")
-		}
+	gitConfigCommand := func() *git.Command {
+		return git.NewCommand(ctx, "config", "--local")
 	}
 
 	// Switch off LFS process (set required, clean and smudge here also)
@@ -366,16 +359,14 @@ func rawMerge(ctx context.Context, pr *issues_model.PullRequest, doer *user_mode
 
 	// Determine if we should sign
 	signArg := ""
-	if git.CheckGitVersionAtLeast("1.7.9") == nil {
-		sign, keyID, signer, _ := asymkey_service.SignMerge(ctx, pr, doer, tmpBasePath, "HEAD", trackingBranch)
-		if sign {
-			signArg = "-S" + keyID
-			if pr.BaseRepo.GetTrustModel() == repo_model.CommitterTrustModel || pr.BaseRepo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
-				committer = signer
-			}
-		} else if git.CheckGitVersionAtLeast("2.0.0") == nil {
-			signArg = "--no-gpg-sign"
+	sign, keyID, signer, _ := asymkey_service.SignMerge(ctx, pr, doer, tmpBasePath, "HEAD", trackingBranch)
+	if sign {
+		signArg = "-S" + keyID
+		if pr.BaseRepo.GetTrustModel() == repo_model.CommitterTrustModel || pr.BaseRepo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
+			committer = signer
 		}
+	} else {
+		signArg = "--no-gpg-sign"
 	}
 
 	commitTimeStr := time.Now().Format(time.RFC3339)
diff --git a/services/repository/files/temp_repo.go b/services/repository/files/temp_repo.go
index 97a80a96bd..1e60d55613 100644
--- a/services/repository/files/temp_repo.go
+++ b/services/repository/files/temp_repo.go
@@ -248,34 +248,31 @@ func (t *TemporaryUploadRepository) CommitTreeWithDate(parent string, author, co
 		args = []string{"commit-tree", treeHash}
 	}
 
-	// Determine if we should sign
-	if git.CheckGitVersionAtLeast("1.7.9") == nil {
-		var sign bool
-		var keyID string
-		var signer *git.Signature
-		if parent != "" {
-			sign, keyID, signer, _ = asymkey_service.SignCRUDAction(t.ctx, t.repo.RepoPath(), author, t.basePath, parent)
-		} else {
-			sign, keyID, signer, _ = asymkey_service.SignInitialCommit(t.ctx, t.repo.RepoPath(), author)
-		}
-		if sign {
-			args = append(args, "-S"+keyID)
-			if t.repo.GetTrustModel() == repo_model.CommitterTrustModel || t.repo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
-				if committerSig.Name != authorSig.Name || committerSig.Email != authorSig.Email {
-					// Add trailers
-					_, _ = messageBytes.WriteString("\n")
-					_, _ = messageBytes.WriteString("Co-authored-by: ")
-					_, _ = messageBytes.WriteString(committerSig.String())
-					_, _ = messageBytes.WriteString("\n")
-					_, _ = messageBytes.WriteString("Co-committed-by: ")
-					_, _ = messageBytes.WriteString(committerSig.String())
-					_, _ = messageBytes.WriteString("\n")
-				}
-				committerSig = signer
+	var sign bool
+	var keyID string
+	var signer *git.Signature
+	if parent != "" {
+		sign, keyID, signer, _ = asymkey_service.SignCRUDAction(t.ctx, t.repo.RepoPath(), author, t.basePath, parent)
+	} else {
+		sign, keyID, signer, _ = asymkey_service.SignInitialCommit(t.ctx, t.repo.RepoPath(), author)
+	}
+	if sign {
+		args = append(args, "-S"+keyID)
+		if t.repo.GetTrustModel() == repo_model.CommitterTrustModel || t.repo.GetTrustModel() == repo_model.CollaboratorCommitterTrustModel {
+			if committerSig.Name != authorSig.Name || committerSig.Email != authorSig.Email {
+				// Add trailers
+				_, _ = messageBytes.WriteString("\n")
+				_, _ = messageBytes.WriteString("Co-authored-by: ")
+				_, _ = messageBytes.WriteString(committerSig.String())
+				_, _ = messageBytes.WriteString("\n")
+				_, _ = messageBytes.WriteString("Co-committed-by: ")
+				_, _ = messageBytes.WriteString(committerSig.String())
+				_, _ = messageBytes.WriteString("\n")
 			}
-		} else if git.CheckGitVersionAtLeast("2.0.0") == nil {
-			args = append(args, "--no-gpg-sign")
+			committerSig = signer
 		}
+	} else {
+		args = append(args, "--no-gpg-sign")
 	}
 
 	if signoff {