Add rebase with merge commit merge style (#3844) (#4052)

Signed-off-by: Julian Tölle <julian.toelle97@gmail.com>

models/fixtures/repo_unit.yml

@@ -30,7 +30,7 @@
   id: 5
   repo_id: 1
   type: 3
-  config: "{\"IgnoreWhitespaceConflicts\":false,\"AllowMerge\":true,\"AllowRebase\":true,\"AllowSquash\":true}"
+  config: "{\"IgnoreWhitespaceConflicts\":false,\"AllowMerge\":true,\"AllowRebase\":true,\"AllowRebaseMerge\":true,\"AllowSquash\":true}"
   created_unix: 946684810
 
 -
@@ -51,7 +51,7 @@
   id: 8
   repo_id: 3
   type: 3
-  config: "{\"IgnoreWhitespaceConflicts\":true,\"AllowMerge\":true,\"AllowRebase\":false,\"AllowSquash\":false}"
+  config: "{\"IgnoreWhitespaceConflicts\":true,\"AllowMerge\":true,\"AllowRebase\":false,\"AllowRebaseMerge\":true,\"AllowSquash\":false}"
   created_unix: 946684810
 
 -

models/migrations/migrations.go

@@ -204,6 +204,8 @@ var migrations = []Migration{
 	NewMigration("add approval whitelists to protected branches", addApprovalWhitelistsToProtectedBranches),
 	// v75 -> v76
 	NewMigration("clear nonused data which not deleted when user was deleted", clearNonusedData),
+	// v76 -> v77
+	NewMigration("add pull request rebase with merge commit", addPullRequestRebaseWithMerge),
 }
 
 // Migrate database to current version

models/migrations/v76.go

@@ -0,0 +1,63 @@
+// Copyright 2018 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"fmt"
+
+	"code.gitea.io/gitea/modules/util"
+
+	"github.com/go-xorm/xorm"
+)
+
+func addPullRequestRebaseWithMerge(x *xorm.Engine) error {
+	// RepoUnit describes all units of a repository
+	type RepoUnit struct {
+		ID          int64
+		RepoID      int64                  `xorm:"INDEX(s)"`
+		Type        int                    `xorm:"INDEX(s)"`
+		Config      map[string]interface{} `xorm:"JSON"`
+		CreatedUnix util.TimeStamp         `xorm:"INDEX CREATED"`
+	}
+
+	sess := x.NewSession()
+	defer sess.Close()
+	if err := sess.Begin(); err != nil {
+		return err
+	}
+
+	//Updating existing issue units
+	units := make([]*RepoUnit, 0, 100)
+	if err := sess.Where("`type` = ?", V16UnitTypePRs).Find(&units); err != nil {
+		return fmt.Errorf("Query repo units: %v", err)
+	}
+	for _, unit := range units {
+		if unit.Config == nil {
+			unit.Config = make(map[string]interface{})
+		}
+		// Allow the new merge style if all other merge styles are allowed
+		allowMergeRebase := true
+
+		if allowMerge, ok := unit.Config["AllowMerge"]; ok {
+			allowMergeRebase = allowMergeRebase && allowMerge.(bool)
+		}
+
+		if allowRebase, ok := unit.Config["AllowRebase"]; ok {
+			allowMergeRebase = allowMergeRebase && allowRebase.(bool)
+		}
+
+		if allowSquash, ok := unit.Config["AllowSquash"]; ok {
+			allowMergeRebase = allowMergeRebase && allowSquash.(bool)
+		}
+
+		if _, ok := unit.Config["AllowRebaseMerge"]; !ok {
+			unit.Config["AllowRebaseMerge"] = allowMergeRebase
+		}
+		if _, err := sess.ID(unit.ID).Cols("config").Update(unit); err != nil {
+			return err
+		}
+	}
+	return sess.Commit()
+}

models/pull.go

@@ -297,6 +297,8 @@ const (
 	MergeStyleMerge MergeStyle = "merge"
 	// MergeStyleRebase rebase before merging
 	MergeStyleRebase MergeStyle = "rebase"
+	// MergeStyleRebaseMerge rebase before merging with merge commit (--no-ff)
+	MergeStyleRebaseMerge MergeStyle = "rebase-merge"
 	// MergeStyleSquash squash commits into single commit before merging
 	MergeStyleSquash MergeStyle = "squash"
 )
@@ -434,6 +436,41 @@ func (pr *PullRequest) Merge(doer *User, baseGitRepo *git.Repository, mergeStyle
 			"git", "merge", "--ff-only", "-q", "head_repo_"+pr.HeadBranch); err != nil {
 			return fmt.Errorf("git merge --ff-only [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
 		}
+	case MergeStyleRebaseMerge:
+		// Checkout head branch
+		if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+			fmt.Sprintf("PullRequest.Merge (git checkout): %s", tmpBasePath),
+			"git", "checkout", "-b", "head_repo_"+pr.HeadBranch, "head_repo/"+pr.HeadBranch); err != nil {
+			return fmt.Errorf("git checkout: %s", stderr)
+		}
+		// Rebase before merging
+		if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+			fmt.Sprintf("PullRequest.Merge (git rebase): %s", tmpBasePath),
+			"git", "rebase", "-q", pr.BaseBranch); err != nil {
+			return fmt.Errorf("git rebase [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
+		}
+		// Checkout base branch again
+		if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+			fmt.Sprintf("PullRequest.Merge (git checkout): %s", tmpBasePath),
+			"git", "checkout", pr.BaseBranch); err != nil {
+			return fmt.Errorf("git checkout: %s", stderr)
+		}
+		// Prepare merge with commit
+		if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+			fmt.Sprintf("PullRequest.Merge (git merge): %s", tmpBasePath),
+			"git", "merge", "--no-ff", "--no-commit", "-q", "head_repo_"+pr.HeadBranch); err != nil {
+			return fmt.Errorf("git merge --no-ff [%s -> %s]: %s", headRepoPath, tmpBasePath, stderr)
+		}
+
+		// Set custom message and author and create merge commit
+		sig := doer.NewGitSig()
+		if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,
+			fmt.Sprintf("PullRequest.Merge (git commit): %s", tmpBasePath),
+			"git", "commit", fmt.Sprintf("--author='%s <%s>'", sig.Name, sig.Email),
+			"-m", message); err != nil {
+			return fmt.Errorf("git commit [%s]: %v - %s", tmpBasePath, err, stderr)
+		}
+
 	case MergeStyleSquash:
 		// Merge with squash
 		if _, stderr, err = process.GetManager().ExecDir(-1, tmpBasePath,

models/repo.go

@@ -1298,7 +1298,7 @@ func createRepository(e *xorm.Session, doer, u *User, repo *Repository) (err err
 			units = append(units, RepoUnit{
 				RepoID: repo.ID,
 				Type:   tp,
-				Config: &PullRequestsConfig{AllowMerge: true, AllowRebase: true, AllowSquash: true},
+				Config: &PullRequestsConfig{AllowMerge: true, AllowRebase: true, AllowRebaseMerge: true, AllowSquash: true},
 			})
 		} else {
 			units = append(units, RepoUnit{

models/repo_unit.go

@@ -91,6 +91,7 @@ type PullRequestsConfig struct {
 	IgnoreWhitespaceConflicts bool
 	AllowMerge                bool
 	AllowRebase               bool
+	AllowRebaseMerge          bool
 	AllowSquash               bool
 }
 
@@ -108,6 +109,7 @@ func (cfg *PullRequestsConfig) ToDB() ([]byte, error) {
 func (cfg *PullRequestsConfig) IsMergeStyleAllowed(mergeStyle MergeStyle) bool {
 	return mergeStyle == MergeStyleMerge && cfg.AllowMerge ||
 		mergeStyle == MergeStyleRebase && cfg.AllowRebase ||
+		mergeStyle == MergeStyleRebaseMerge && cfg.AllowRebaseMerge ||
 		mergeStyle == MergeStyleSquash && cfg.AllowSquash
 }