Branches not at ref commit ID should not be listed as Merged (#9614)

Once a branch has been merged if the commit ID no longer equals that of
the pulls ref commit id don't offer to delete the branch on the pull screen
and don't list it as merged on branches.

Fix #9201

When looking at the pull page we should also get the commits from the refs/pulls/x/head

Fix #9158

integrations/gitea-repositories-meta/user2/repo1.git/refs/pull/3/head

@@ -0,0 +1 @@
+4a357436d925b5c974181ff12a994538ddc5a269

models/pull.go

@@ -122,7 +122,7 @@ func (pr *PullRequest) LoadHeadRepo() error {
 		if has, err := x.ID(pr.HeadRepoID).Get(&repo); err != nil {
 			return err
 		} else if !has {
-			return ErrRepoNotExist{ID: pr.BaseRepoID}
+			return ErrRepoNotExist{ID: pr.HeadRepoID}
 		}
 		pr.HeadRepo = &repo
 	}

routers/repo/branch.go

@@ -16,6 +16,7 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/repofiles"
 	"code.gitea.io/gitea/modules/util"
+	"gopkg.in/src-d/go-git.v4/plumbing"
 )
 
 const (
@@ -33,6 +34,7 @@ type Branch struct {
 	CommitsAhead      int
 	CommitsBehind     int
 	LatestPullRequest *models.PullRequest
+	MergeMovedOn      bool
 }
 
 // Branches render repository branch page
@@ -185,6 +187,12 @@ func loadBranches(ctx *context.Context) []*Branch {
 		return nil
 	}
 
+	repoIDToRepo := map[int64]*models.Repository{}
+	repoIDToRepo[ctx.Repo.Repository.ID] = ctx.Repo.Repository
+
+	repoIDToGitRepo := map[int64]*git.Repository{}
+	repoIDToGitRepo[ctx.Repo.Repository.ID] = ctx.Repo.GitRepo
+
 	branches := make([]*Branch, len(rawBranches))
 	for i := range rawBranches {
 		commit, err := rawBranches[i].GetCommit()
@@ -213,11 +221,46 @@ func loadBranches(ctx *context.Context) []*Branch {
 			ctx.ServerError("GetLatestPullRequestByHeadInfo", err)
 			return nil
 		}
+		headCommit := commit.ID.String()
+
+		mergeMovedOn := false
 		if pr != nil {
+			pr.HeadRepo = ctx.Repo.Repository
 			if err := pr.LoadIssue(); err != nil {
 				ctx.ServerError("pr.LoadIssue", err)
 				return nil
 			}
+			if repo, ok := repoIDToRepo[pr.BaseRepoID]; ok {
+				pr.BaseRepo = repo
+			} else if err := pr.LoadBaseRepo(); err != nil {
+				ctx.ServerError("pr.LoadBaseRepo", err)
+				return nil
+			} else {
+				repoIDToRepo[pr.BaseRepoID] = pr.BaseRepo
+			}
+
+			if pr.HasMerged {
+				baseGitRepo, ok := repoIDToGitRepo[pr.BaseRepoID]
+				if !ok {
+					baseGitRepo, err = git.OpenRepository(pr.BaseRepo.RepoPath())
+					if err != nil {
+						ctx.ServerError("OpenRepository", err)
+						return nil
+					}
+					defer baseGitRepo.Close()
+					repoIDToGitRepo[pr.BaseRepoID] = baseGitRepo
+				}
+				pullCommit, err := baseGitRepo.GetRefCommitID(pr.GetGitRefName())
+				if err != nil && err != plumbing.ErrReferenceNotFound {
+					ctx.ServerError("GetBranchCommitID", err)
+					return nil
+				}
+				if err == nil && headCommit != pullCommit {
+					// the head has moved on from the merge - we shouldn't delete
+					mergeMovedOn = true
+				}
+			}
+
 		}
 
 		isIncluded := divergence.Ahead == 0 && ctx.Repo.Repository.DefaultBranch != branchName
@@ -230,6 +273,7 @@ func loadBranches(ctx *context.Context) []*Branch {
 			CommitsAhead:      divergence.Ahead,
 			CommitsBehind:     divergence.Behind,
 			LatestPullRequest: pr,
+			MergeMovedOn:      mergeMovedOn,
 		}
 	}
 

routers/repo/issue.go

@@ -966,7 +966,10 @@ func ViewIssue(ctx *context.Context) {
 			ctx.Data["IsBlockedByRejection"] = pull.ProtectedBranch.MergeBlockedByRejectedReview(pull)
 			ctx.Data["GrantedApprovals"] = cnt
 		}
-		ctx.Data["IsPullBranchDeletable"] = canDelete && pull.HeadRepo != nil && git.IsBranchExist(pull.HeadRepo.RepoPath(), pull.HeadBranch)
+		ctx.Data["IsPullBranchDeletable"] = canDelete &&
+			pull.HeadRepo != nil &&
+			git.IsBranchExist(pull.HeadRepo.RepoPath(), pull.HeadBranch) &&
+			(!pull.HasMerged || ctx.Data["HeadBranchCommitID"] == ctx.Data["PullHeadCommitID"])
 
 		ctx.Data["PullReviewers"], err = models.GetReviewersByIssueID(issue.ID)
 		if err != nil {

routers/repo/pull.go

@@ -330,25 +330,37 @@ func PrepareViewPullInfo(ctx *context.Context, issue *models.Issue) *git.Compare
 	repo := ctx.Repo.Repository
 	pull := issue.PullRequest
 
-	var err error
+	if err := pull.GetHeadRepo(); err != nil {
-	if err = pull.GetHeadRepo(); err != nil {
 		ctx.ServerError("GetHeadRepo", err)
 		return nil
 	}
 
+	if err := pull.GetBaseRepo(); err != nil {
+		ctx.ServerError("GetBaseRepo", err)
+		return nil
+	}
+
 	setMergeTarget(ctx, pull)
 
-	if err = pull.LoadProtectedBranch(); err != nil {
+	if err := pull.LoadProtectedBranch(); err != nil {
 		ctx.ServerError("GetLatestCommitStatus", err)
 		return nil
 	}
 	ctx.Data["EnableStatusCheck"] = pull.ProtectedBranch != nil && pull.ProtectedBranch.EnableStatusCheck
 
-	var headGitRepo *git.Repository
+	baseGitRepo, err := git.OpenRepository(pull.BaseRepo.RepoPath())
+	if err != nil {
+		ctx.ServerError("OpenRepository", err)
+		return nil
+	}
+	defer baseGitRepo.Close()
 	var headBranchExist bool
+	var headBranchSha string
 	// HeadRepo may be missing
 	if pull.HeadRepo != nil {
-		headGitRepo, err = git.OpenRepository(pull.HeadRepo.RepoPath())
+		var err error
+
+		headGitRepo, err := git.OpenRepository(pull.HeadRepo.RepoPath())
 		if err != nil {
 			ctx.ServerError("OpenRepository", err)
 			return nil
@@ -358,11 +370,19 @@ func PrepareViewPullInfo(ctx *context.Context, issue *models.Issue) *git.Compare
 		headBranchExist = headGitRepo.IsBranchExist(pull.HeadBranch)
 
 		if headBranchExist {
-			sha, err := headGitRepo.GetBranchCommitID(pull.HeadBranch)
+			headBranchSha, err = headGitRepo.GetBranchCommitID(pull.HeadBranch)
 			if err != nil {
 				ctx.ServerError("GetBranchCommitID", err)
 				return nil
 			}
+		}
+	}
+
+	sha, err := baseGitRepo.GetRefCommitID(pull.GetGitRefName())
+	if err != nil {
+		ctx.ServerError(fmt.Sprintf("GetRefCommitID(%s)", pull.GetGitRefName()), err)
+		return nil
+	}
 
 	commitStatuses, err := models.GetLatestCommitStatus(repo, sha, 0)
 	if err != nil {
@@ -385,19 +405,18 @@ func PrepareViewPullInfo(ctx *context.Context, issue *models.Issue) *git.Compare
 		}
 		ctx.Data["IsRequiredStatusCheckSuccess"] = pull_service.IsCommitStatusContextSuccess(commitStatuses, pull.ProtectedBranch.StatusCheckContexts)
 	}
-		}
-	}
 
-	if pull.HeadRepo == nil || !headBranchExist {
+	ctx.Data["HeadBranchMovedOn"] = headBranchSha != sha
+	ctx.Data["HeadBranchCommitID"] = headBranchSha
+	ctx.Data["PullHeadCommitID"] = sha
+
+	if pull.HeadRepo == nil || !headBranchExist || headBranchSha != sha {
 		ctx.Data["IsPullRequestBroken"] = true
 		ctx.Data["HeadTarget"] = "deleted"
-		ctx.Data["NumCommits"] = 0
-		ctx.Data["NumFiles"] = 0
-		return nil
 	}
 
-	compareInfo, err := headGitRepo.GetCompareInfo(models.RepoPath(repo.Owner.Name, repo.Name),
+	compareInfo, err := baseGitRepo.GetCompareInfo(pull.BaseRepo.RepoPath(),
-		pull.BaseBranch, pull.HeadBranch)
+		pull.BaseBranch, pull.GetGitRefName())
 	if err != nil {
 		if strings.Contains(err.Error(), "fatal: Not a valid object name") {
 			ctx.Data["IsPullRequestBroken"] = true

templates/repo/branch/list.tmpl

@@ -84,6 +84,12 @@
 												<button id="new-pull-request" class="ui compact basic button">{{$.i18n.Tr "repo.pulls.compare_changes"}}</button>
 											</a>
 											{{end}}
+										{{else if and .LatestPullRequest.HasMerged .MergeMovedOn}}
+											{{if and (not .IsDeleted) $.AllowsPulls (gt .CommitsAhead 0)}}
+											<a href="{{$.RepoLink}}/compare/{{$.DefaultBranch | EscapePound}}...{{if ne $.Repository.Owner.Name $.Owner.Name}}{{$.Owner.Name}}:{{end}}{{.Name | EscapePound}}">
+												<button id="new-pull-request" class="ui compact basic button">{{$.i18n.Tr "repo.pulls.compare_changes"}}</button>
+											</a>
+											{{end}}
 										{{else}}
 											<a href="{{$.RepoLink}}/pulls/{{.LatestPullRequest.Issue.Index}}">#{{.LatestPullRequest.Issue.Index}}</a>
 											{{if .LatestPullRequest.HasMerged}}

templates/repo/issue/view_content/pull.tmpl

@@ -72,7 +72,7 @@
 						{{$.i18n.Tr "repo.pulls.reopen_to_merge"}}
 					{{end}}
 				</div>
-				{{if .IsPullBranchDeletable}}
+				{{if and .IsPullBranchDeletable ( not .IsPullRequestBroken )}}
 					<div class="ui divider"></div>
 					<div>
 						<a class="delete-button ui red button" href="" data-url="{{.DeleteBranchLink}}">{{$.i18n.Tr "repo.branch.delete" .HeadTarget}}</a>