1// Copyright 2015 The Gogs Authors. All rights reserved.
2// Copyright 2019 The Gitea Authors. All rights reserved.
3// Use of this source code is governed by a MIT-style
4// license that can be found in the LICENSE file.
5
6package models
7
8import (
9	"context"
10	"fmt"
11	"io"
12	"strings"
13
14	"code.gitea.io/gitea/models/db"
15	repo_model "code.gitea.io/gitea/models/repo"
16	"code.gitea.io/gitea/models/unit"
17	user_model "code.gitea.io/gitea/models/user"
18	"code.gitea.io/gitea/modules/git"
19	"code.gitea.io/gitea/modules/log"
20	"code.gitea.io/gitea/modules/setting"
21	"code.gitea.io/gitea/modules/timeutil"
22	"code.gitea.io/gitea/modules/util"
23)
24
25// PullRequestType defines pull request type
26type PullRequestType int
27
28// Enumerate all the pull request types
29const (
30	PullRequestGitea PullRequestType = iota
31	PullRequestGit
32)
33
34// PullRequestStatus defines pull request status
35type PullRequestStatus int
36
37// Enumerate all the pull request status
38const (
39	PullRequestStatusConflict PullRequestStatus = iota
40	PullRequestStatusChecking
41	PullRequestStatusMergeable
42	PullRequestStatusManuallyMerged
43	PullRequestStatusError
44	PullRequestStatusEmpty
45)
46
47// PullRequestFlow the flow of pull request
48type PullRequestFlow int
49
50const (
51	// PullRequestFlowGithub github flow from head branch to base branch
52	PullRequestFlowGithub PullRequestFlow = iota
53	// PullRequestFlowAGit Agit flow pull request, head branch is not exist
54	PullRequestFlowAGit
55)
56
57// PullRequest represents relation between pull request and repositories.
58type PullRequest struct {
59	ID              int64 `xorm:"pk autoincr"`
60	Type            PullRequestType
61	Status          PullRequestStatus
62	ConflictedFiles []string `xorm:"TEXT JSON"`
63	CommitsAhead    int
64	CommitsBehind   int
65
66	ChangedProtectedFiles []string `xorm:"TEXT JSON"`
67
68	IssueID int64  `xorm:"INDEX"`
69	Issue   *Issue `xorm:"-"`
70	Index   int64
71
72	HeadRepoID      int64                  `xorm:"INDEX"`
73	HeadRepo        *repo_model.Repository `xorm:"-"`
74	BaseRepoID      int64                  `xorm:"INDEX"`
75	BaseRepo        *repo_model.Repository `xorm:"-"`
76	HeadBranch      string
77	HeadCommitID    string `xorm:"-"`
78	BaseBranch      string
79	ProtectedBranch *ProtectedBranch `xorm:"-"`
80	MergeBase       string           `xorm:"VARCHAR(40)"`
81
82	HasMerged      bool               `xorm:"INDEX"`
83	MergedCommitID string             `xorm:"VARCHAR(40)"`
84	MergerID       int64              `xorm:"INDEX"`
85	Merger         *user_model.User   `xorm:"-"`
86	MergedUnix     timeutil.TimeStamp `xorm:"updated INDEX"`
87
88	isHeadRepoLoaded bool `xorm:"-"`
89
90	Flow PullRequestFlow `xorm:"NOT NULL DEFAULT 0"`
91}
92
93func init() {
94	db.RegisterModel(new(PullRequest))
95}
96
97// MustHeadUserName returns the HeadRepo's username if failed return blank
98func (pr *PullRequest) MustHeadUserName() string {
99	if err := pr.LoadHeadRepo(); err != nil {
100		if !repo_model.IsErrRepoNotExist(err) {
101			log.Error("LoadHeadRepo: %v", err)
102		} else {
103			log.Warn("LoadHeadRepo %d but repository does not exist: %v", pr.HeadRepoID, err)
104		}
105		return ""
106	}
107	if pr.HeadRepo == nil {
108		return ""
109	}
110	return pr.HeadRepo.OwnerName
111}
112
113// Note: don't try to get Issue because will end up recursive querying.
114func (pr *PullRequest) loadAttributes(e db.Engine) (err error) {
115	if pr.HasMerged && pr.Merger == nil {
116		pr.Merger, err = user_model.GetUserByIDEngine(e, pr.MergerID)
117		if user_model.IsErrUserNotExist(err) {
118			pr.MergerID = -1
119			pr.Merger = user_model.NewGhostUser()
120		} else if err != nil {
121			return fmt.Errorf("getUserByID [%d]: %v", pr.MergerID, err)
122		}
123	}
124
125	return nil
126}
127
128// LoadAttributes loads pull request attributes from database
129func (pr *PullRequest) LoadAttributes() error {
130	return pr.loadAttributes(db.GetEngine(db.DefaultContext))
131}
132
133func (pr *PullRequest) loadHeadRepo(ctx context.Context) (err error) {
134	if !pr.isHeadRepoLoaded && pr.HeadRepo == nil && pr.HeadRepoID > 0 {
135		if pr.HeadRepoID == pr.BaseRepoID {
136			if pr.BaseRepo != nil {
137				pr.HeadRepo = pr.BaseRepo
138				return nil
139			} else if pr.Issue != nil && pr.Issue.Repo != nil {
140				pr.HeadRepo = pr.Issue.Repo
141				return nil
142			}
143		}
144
145		pr.HeadRepo, err = repo_model.GetRepositoryByIDCtx(ctx, pr.HeadRepoID)
146		if err != nil && !repo_model.IsErrRepoNotExist(err) { // Head repo maybe deleted, but it should still work
147			return fmt.Errorf("getRepositoryByID(head): %v", err)
148		}
149		pr.isHeadRepoLoaded = true
150	}
151	return nil
152}
153
154// LoadHeadRepo loads the head repository
155func (pr *PullRequest) LoadHeadRepo() error {
156	return pr.loadHeadRepo(db.DefaultContext)
157}
158
159// LoadBaseRepo loads the target repository
160func (pr *PullRequest) LoadBaseRepo() error {
161	return pr.loadBaseRepo(db.DefaultContext)
162}
163
164func (pr *PullRequest) loadBaseRepo(ctx context.Context) (err error) {
165	if pr.BaseRepo != nil {
166		return nil
167	}
168
169	if pr.HeadRepoID == pr.BaseRepoID && pr.HeadRepo != nil {
170		pr.BaseRepo = pr.HeadRepo
171		return nil
172	}
173
174	if pr.Issue != nil && pr.Issue.Repo != nil {
175		pr.BaseRepo = pr.Issue.Repo
176		return nil
177	}
178
179	pr.BaseRepo, err = repo_model.GetRepositoryByIDCtx(ctx, pr.BaseRepoID)
180	if err != nil {
181		return fmt.Errorf("repo_model.GetRepositoryByID(base): %v", err)
182	}
183	return nil
184}
185
186// LoadIssue loads issue information from database
187func (pr *PullRequest) LoadIssue() (err error) {
188	return pr.loadIssue(db.GetEngine(db.DefaultContext))
189}
190
191func (pr *PullRequest) loadIssue(e db.Engine) (err error) {
192	if pr.Issue != nil {
193		return nil
194	}
195
196	pr.Issue, err = getIssueByID(e, pr.IssueID)
197	if err == nil {
198		pr.Issue.PullRequest = pr
199	}
200	return err
201}
202
203// LoadProtectedBranch loads the protected branch of the base branch
204func (pr *PullRequest) LoadProtectedBranch() (err error) {
205	return pr.loadProtectedBranch(db.DefaultContext)
206}
207
208func (pr *PullRequest) loadProtectedBranch(ctx context.Context) (err error) {
209	if pr.ProtectedBranch == nil {
210		if pr.BaseRepo == nil {
211			if pr.BaseRepoID == 0 {
212				return nil
213			}
214			pr.BaseRepo, err = repo_model.GetRepositoryByIDCtx(ctx, pr.BaseRepoID)
215			if err != nil {
216				return
217			}
218		}
219		pr.ProtectedBranch, err = getProtectedBranchBy(db.GetEngine(ctx), pr.BaseRepo.ID, pr.BaseBranch)
220	}
221	return
222}
223
224// GetDefaultMergeMessage returns default message used when merging pull request
225func (pr *PullRequest) GetDefaultMergeMessage() string {
226	if pr.HeadRepo == nil {
227		var err error
228		pr.HeadRepo, err = repo_model.GetRepositoryByID(pr.HeadRepoID)
229		if err != nil {
230			log.Error("GetRepositoryById[%d]: %v", pr.HeadRepoID, err)
231			return ""
232		}
233	}
234	if err := pr.LoadIssue(); err != nil {
235		log.Error("Cannot load issue %d for PR id %d: Error: %v", pr.IssueID, pr.ID, err)
236		return ""
237	}
238	if err := pr.LoadBaseRepo(); err != nil {
239		log.Error("LoadBaseRepo: %v", err)
240		return ""
241	}
242
243	issueReference := "#"
244	if pr.BaseRepo.UnitEnabled(unit.TypeExternalTracker) {
245		issueReference = "!"
246	}
247
248	if pr.BaseRepoID == pr.HeadRepoID {
249		return fmt.Sprintf("Merge pull request '%s' (%s%d) from %s into %s", pr.Issue.Title, issueReference, pr.Issue.Index, pr.HeadBranch, pr.BaseBranch)
250	}
251
252	return fmt.Sprintf("Merge pull request '%s' (%s%d) from %s:%s into %s", pr.Issue.Title, issueReference, pr.Issue.Index, pr.HeadRepo.FullName(), pr.HeadBranch, pr.BaseBranch)
253}
254
255// ReviewCount represents a count of Reviews
256type ReviewCount struct {
257	IssueID int64
258	Type    ReviewType
259	Count   int64
260}
261
262// GetApprovalCounts returns the approval counts by type
263// FIXME: Only returns official counts due to double counting of non-official counts
264func (pr *PullRequest) GetApprovalCounts() ([]*ReviewCount, error) {
265	return pr.getApprovalCounts(db.GetEngine(db.DefaultContext))
266}
267
268func (pr *PullRequest) getApprovalCounts(e db.Engine) ([]*ReviewCount, error) {
269	rCounts := make([]*ReviewCount, 0, 6)
270	sess := e.Where("issue_id = ?", pr.IssueID)
271	return rCounts, sess.Select("issue_id, type, count(id) as `count`").Where("official = ? AND dismissed = ?", true, false).GroupBy("issue_id, type").Table("review").Find(&rCounts)
272}
273
274// GetApprovers returns the approvers of the pull request
275func (pr *PullRequest) GetApprovers() string {
276	stringBuilder := strings.Builder{}
277	if err := pr.getReviewedByLines(&stringBuilder); err != nil {
278		log.Error("Unable to getReviewedByLines: Error: %v", err)
279		return ""
280	}
281
282	return stringBuilder.String()
283}
284
285func (pr *PullRequest) getReviewedByLines(writer io.Writer) error {
286	maxReviewers := setting.Repository.PullRequest.DefaultMergeMessageMaxApprovers
287
288	if maxReviewers == 0 {
289		return nil
290	}
291
292	ctx, committer, err := db.TxContext()
293	if err != nil {
294		return err
295	}
296	defer committer.Close()
297	sess := db.GetEngine(ctx)
298
299	// Note: This doesn't page as we only expect a very limited number of reviews
300	reviews, err := findReviews(sess, FindReviewOptions{
301		Type:         ReviewTypeApprove,
302		IssueID:      pr.IssueID,
303		OfficialOnly: setting.Repository.PullRequest.DefaultMergeMessageOfficialApproversOnly,
304	})
305	if err != nil {
306		log.Error("Unable to FindReviews for PR ID %d: %v", pr.ID, err)
307		return err
308	}
309
310	reviewersWritten := 0
311
312	for _, review := range reviews {
313		if maxReviewers > 0 && reviewersWritten > maxReviewers {
314			break
315		}
316
317		if err := review.loadReviewer(sess); err != nil && !user_model.IsErrUserNotExist(err) {
318			log.Error("Unable to LoadReviewer[%d] for PR ID %d : %v", review.ReviewerID, pr.ID, err)
319			return err
320		} else if review.Reviewer == nil {
321			continue
322		}
323		if _, err := writer.Write([]byte("Reviewed-by: ")); err != nil {
324			return err
325		}
326		if _, err := writer.Write([]byte(review.Reviewer.NewGitSig().String())); err != nil {
327			return err
328		}
329		if _, err := writer.Write([]byte{'\n'}); err != nil {
330			return err
331		}
332		reviewersWritten++
333	}
334	return committer.Commit()
335}
336
337// GetDefaultSquashMessage returns default message used when squash and merging pull request
338func (pr *PullRequest) GetDefaultSquashMessage() string {
339	if err := pr.LoadIssue(); err != nil {
340		log.Error("LoadIssue: %v", err)
341		return ""
342	}
343	if err := pr.LoadBaseRepo(); err != nil {
344		log.Error("LoadBaseRepo: %v", err)
345		return ""
346	}
347	if pr.BaseRepo.UnitEnabled(unit.TypeExternalTracker) {
348		return fmt.Sprintf("%s (!%d)", pr.Issue.Title, pr.Issue.Index)
349	}
350	return fmt.Sprintf("%s (#%d)", pr.Issue.Title, pr.Issue.Index)
351}
352
353// GetGitRefName returns git ref for hidden pull request branch
354func (pr *PullRequest) GetGitRefName() string {
355	return fmt.Sprintf("%s%d/head", git.PullPrefix, pr.Index)
356}
357
358// IsChecking returns true if this pull request is still checking conflict.
359func (pr *PullRequest) IsChecking() bool {
360	return pr.Status == PullRequestStatusChecking
361}
362
363// CanAutoMerge returns true if this pull request can be merged automatically.
364func (pr *PullRequest) CanAutoMerge() bool {
365	return pr.Status == PullRequestStatusMergeable
366}
367
368// IsEmpty returns true if this pull request is empty.
369func (pr *PullRequest) IsEmpty() bool {
370	return pr.Status == PullRequestStatusEmpty
371}
372
373// SetMerged sets a pull request to merged and closes the corresponding issue
374func (pr *PullRequest) SetMerged() (bool, error) {
375	if pr.HasMerged {
376		return false, fmt.Errorf("PullRequest[%d] already merged", pr.Index)
377	}
378	if pr.MergedCommitID == "" || pr.MergedUnix == 0 || pr.Merger == nil {
379		return false, fmt.Errorf("Unable to merge PullRequest[%d], some required fields are empty", pr.Index)
380	}
381
382	pr.HasMerged = true
383
384	ctx, committer, err := db.TxContext()
385	if err != nil {
386		return false, err
387	}
388	defer committer.Close()
389	sess := db.GetEngine(ctx)
390
391	if _, err := sess.Exec("UPDATE `issue` SET `repo_id` = `repo_id` WHERE `id` = ?", pr.IssueID); err != nil {
392		return false, err
393	}
394
395	if _, err := sess.Exec("UPDATE `pull_request` SET `issue_id` = `issue_id` WHERE `id` = ?", pr.ID); err != nil {
396		return false, err
397	}
398
399	pr.Issue = nil
400	if err := pr.loadIssue(sess); err != nil {
401		return false, err
402	}
403
404	if tmpPr, err := getPullRequestByID(sess, pr.ID); err != nil {
405		return false, err
406	} else if tmpPr.HasMerged {
407		if pr.Issue.IsClosed {
408			return false, nil
409		}
410		return false, fmt.Errorf("PullRequest[%d] already merged but it's associated issue [%d] is not closed", pr.Index, pr.IssueID)
411	} else if pr.Issue.IsClosed {
412		return false, fmt.Errorf("PullRequest[%d] already closed", pr.Index)
413	}
414
415	if err := pr.Issue.loadRepo(ctx); err != nil {
416		return false, err
417	}
418
419	if err := pr.Issue.Repo.GetOwner(ctx); err != nil {
420		return false, err
421	}
422
423	if _, err := pr.Issue.changeStatus(ctx, pr.Merger, true, true); err != nil {
424		return false, fmt.Errorf("Issue.changeStatus: %v", err)
425	}
426
427	// We need to save all of the data used to compute this merge as it may have already been changed by TestPatch. FIXME: need to set some state to prevent TestPatch from running whilst we are merging.
428	if _, err := sess.Where("id = ?", pr.ID).Cols("has_merged, status, merge_base, merged_commit_id, merger_id, merged_unix").Update(pr); err != nil {
429		return false, fmt.Errorf("Failed to update pr[%d]: %v", pr.ID, err)
430	}
431
432	if err := committer.Commit(); err != nil {
433		return false, fmt.Errorf("Commit: %v", err)
434	}
435	return true, nil
436}
437
438// NewPullRequest creates new pull request with labels for repository.
439func NewPullRequest(repo *repo_model.Repository, issue *Issue, labelIDs []int64, uuids []string, pr *PullRequest) (err error) {
440	idx, err := db.GetNextResourceIndex("issue_index", repo.ID)
441	if err != nil {
442		return fmt.Errorf("generate pull request index failed: %v", err)
443	}
444
445	issue.Index = idx
446
447	ctx, committer, err := db.TxContext()
448	if err != nil {
449		return err
450	}
451	defer committer.Close()
452
453	if err = newIssue(ctx, issue.Poster, NewIssueOptions{
454		Repo:        repo,
455		Issue:       issue,
456		LabelIDs:    labelIDs,
457		Attachments: uuids,
458		IsPull:      true,
459	}); err != nil {
460		if IsErrUserDoesNotHaveAccessToRepo(err) || IsErrNewIssueInsert(err) {
461			return err
462		}
463		return fmt.Errorf("newIssue: %v", err)
464	}
465
466	pr.Index = issue.Index
467	pr.BaseRepo = repo
468	pr.IssueID = issue.ID
469	if err = db.Insert(ctx, pr); err != nil {
470		return fmt.Errorf("insert pull repo: %v", err)
471	}
472
473	if err = committer.Commit(); err != nil {
474		return fmt.Errorf("Commit: %v", err)
475	}
476
477	return nil
478}
479
480// GetUnmergedPullRequest returns a pull request that is open and has not been merged
481// by given head/base and repo/branch.
482func GetUnmergedPullRequest(headRepoID, baseRepoID int64, headBranch, baseBranch string, flow PullRequestFlow) (*PullRequest, error) {
483	pr := new(PullRequest)
484	has, err := db.GetEngine(db.DefaultContext).
485		Where("head_repo_id=? AND head_branch=? AND base_repo_id=? AND base_branch=? AND has_merged=? AND flow = ? AND issue.is_closed=?",
486			headRepoID, headBranch, baseRepoID, baseBranch, false, flow, false).
487		Join("INNER", "issue", "issue.id=pull_request.issue_id").
488		Get(pr)
489	if err != nil {
490		return nil, err
491	} else if !has {
492		return nil, ErrPullRequestNotExist{0, 0, headRepoID, baseRepoID, headBranch, baseBranch}
493	}
494
495	return pr, nil
496}
497
498// GetLatestPullRequestByHeadInfo returns the latest pull request (regardless of its status)
499// by given head information (repo and branch).
500func GetLatestPullRequestByHeadInfo(repoID int64, branch string) (*PullRequest, error) {
501	pr := new(PullRequest)
502	has, err := db.GetEngine(db.DefaultContext).
503		Where("head_repo_id = ? AND head_branch = ? AND flow = ?", repoID, branch, PullRequestFlowGithub).
504		OrderBy("id DESC").
505		Get(pr)
506	if !has {
507		return nil, err
508	}
509	return pr, err
510}
511
512// GetPullRequestByIndex returns a pull request by the given index
513func GetPullRequestByIndex(repoID, index int64) (*PullRequest, error) {
514	if index < 1 {
515		return nil, ErrPullRequestNotExist{}
516	}
517	pr := &PullRequest{
518		BaseRepoID: repoID,
519		Index:      index,
520	}
521
522	has, err := db.GetEngine(db.DefaultContext).Get(pr)
523	if err != nil {
524		return nil, err
525	} else if !has {
526		return nil, ErrPullRequestNotExist{0, 0, 0, repoID, "", ""}
527	}
528
529	if err = pr.LoadAttributes(); err != nil {
530		return nil, err
531	}
532	if err = pr.LoadIssue(); err != nil {
533		return nil, err
534	}
535
536	return pr, nil
537}
538
539func getPullRequestByID(e db.Engine, id int64) (*PullRequest, error) {
540	pr := new(PullRequest)
541	has, err := e.ID(id).Get(pr)
542	if err != nil {
543		return nil, err
544	} else if !has {
545		return nil, ErrPullRequestNotExist{id, 0, 0, 0, "", ""}
546	}
547	return pr, pr.loadAttributes(e)
548}
549
550// GetPullRequestByID returns a pull request by given ID.
551func GetPullRequestByID(id int64) (*PullRequest, error) {
552	return getPullRequestByID(db.GetEngine(db.DefaultContext), id)
553}
554
555// GetPullRequestByIssueIDWithNoAttributes returns pull request with no attributes loaded by given issue ID.
556func GetPullRequestByIssueIDWithNoAttributes(issueID int64) (*PullRequest, error) {
557	var pr PullRequest
558	has, err := db.GetEngine(db.DefaultContext).Where("issue_id = ?", issueID).Get(&pr)
559	if err != nil {
560		return nil, err
561	}
562	if !has {
563		return nil, ErrPullRequestNotExist{0, issueID, 0, 0, "", ""}
564	}
565	return &pr, nil
566}
567
568func getPullRequestByIssueID(e db.Engine, issueID int64) (*PullRequest, error) {
569	pr := &PullRequest{
570		IssueID: issueID,
571	}
572	has, err := e.Get(pr)
573	if err != nil {
574		return nil, err
575	} else if !has {
576		return nil, ErrPullRequestNotExist{0, issueID, 0, 0, "", ""}
577	}
578	return pr, pr.loadAttributes(e)
579}
580
581// GetAllUnmergedAgitPullRequestByPoster get all unmerged agit flow pull request
582// By poster id.
583func GetAllUnmergedAgitPullRequestByPoster(uid int64) ([]*PullRequest, error) {
584	pulls := make([]*PullRequest, 0, 10)
585
586	err := db.GetEngine(db.DefaultContext).
587		Where("has_merged=? AND flow = ? AND issue.is_closed=? AND issue.poster_id=?",
588			false, PullRequestFlowAGit, false, uid).
589		Join("INNER", "issue", "issue.id=pull_request.issue_id").
590		Find(&pulls)
591
592	return pulls, err
593}
594
595// GetPullRequestByIssueID returns pull request by given issue ID.
596func GetPullRequestByIssueID(issueID int64) (*PullRequest, error) {
597	return getPullRequestByIssueID(db.GetEngine(db.DefaultContext), issueID)
598}
599
600// Update updates all fields of pull request.
601func (pr *PullRequest) Update() error {
602	_, err := db.GetEngine(db.DefaultContext).ID(pr.ID).AllCols().Update(pr)
603	return err
604}
605
606// UpdateCols updates specific fields of pull request.
607func (pr *PullRequest) UpdateCols(cols ...string) error {
608	_, err := db.GetEngine(db.DefaultContext).ID(pr.ID).Cols(cols...).Update(pr)
609	return err
610}
611
612// UpdateColsIfNotMerged updates specific fields of a pull request if it has not been merged
613func (pr *PullRequest) UpdateColsIfNotMerged(cols ...string) error {
614	_, err := db.GetEngine(db.DefaultContext).Where("id = ? AND has_merged = ?", pr.ID, false).Cols(cols...).Update(pr)
615	return err
616}
617
618// IsWorkInProgress determine if the Pull Request is a Work In Progress by its title
619func (pr *PullRequest) IsWorkInProgress() bool {
620	if err := pr.LoadIssue(); err != nil {
621		log.Error("LoadIssue: %v", err)
622		return false
623	}
624	return HasWorkInProgressPrefix(pr.Issue.Title)
625}
626
627// HasWorkInProgressPrefix determines if the given PR title has a Work In Progress prefix
628func HasWorkInProgressPrefix(title string) bool {
629	for _, prefix := range setting.Repository.PullRequest.WorkInProgressPrefixes {
630		if strings.HasPrefix(strings.ToUpper(title), prefix) {
631			return true
632		}
633	}
634	return false
635}
636
637// IsFilesConflicted determines if the  Pull Request has changes conflicting with the target branch.
638func (pr *PullRequest) IsFilesConflicted() bool {
639	return len(pr.ConflictedFiles) > 0
640}
641
642// GetWorkInProgressPrefix returns the prefix used to mark the pull request as a work in progress.
643// It returns an empty string when none were found
644func (pr *PullRequest) GetWorkInProgressPrefix() string {
645	if err := pr.LoadIssue(); err != nil {
646		log.Error("LoadIssue: %v", err)
647		return ""
648	}
649
650	for _, prefix := range setting.Repository.PullRequest.WorkInProgressPrefixes {
651		if strings.HasPrefix(strings.ToUpper(pr.Issue.Title), prefix) {
652			return pr.Issue.Title[0:len(prefix)]
653		}
654	}
655	return ""
656}
657
658// UpdateCommitDivergence update Divergence of a pull request
659func (pr *PullRequest) UpdateCommitDivergence(ahead, behind int) error {
660	return pr.updateCommitDivergence(db.GetEngine(db.DefaultContext), ahead, behind)
661}
662
663func (pr *PullRequest) updateCommitDivergence(e db.Engine, ahead, behind int) error {
664	if pr.ID == 0 {
665		return fmt.Errorf("pull ID is 0")
666	}
667	pr.CommitsAhead = ahead
668	pr.CommitsBehind = behind
669	_, err := e.ID(pr.ID).Cols("commits_ahead", "commits_behind").Update(pr)
670	return err
671}
672
673// IsSameRepo returns true if base repo and head repo is the same
674func (pr *PullRequest) IsSameRepo() bool {
675	return pr.BaseRepoID == pr.HeadRepoID
676}
677
678// GetBaseBranchHTMLURL returns the HTML URL of the base branch
679func (pr *PullRequest) GetBaseBranchHTMLURL() string {
680	if err := pr.LoadBaseRepo(); err != nil {
681		log.Error("LoadBaseRepo: %v", err)
682		return ""
683	}
684	if pr.BaseRepo == nil {
685		return ""
686	}
687	return pr.BaseRepo.HTMLURL() + "/src/branch/" + util.PathEscapeSegments(pr.BaseBranch)
688}
689
690// GetHeadBranchHTMLURL returns the HTML URL of the head branch
691func (pr *PullRequest) GetHeadBranchHTMLURL() string {
692	if pr.Flow == PullRequestFlowAGit {
693		return ""
694	}
695
696	if err := pr.LoadHeadRepo(); err != nil {
697		log.Error("LoadHeadRepo: %v", err)
698		return ""
699	}
700	if pr.HeadRepo == nil {
701		return ""
702	}
703	return pr.HeadRepo.HTMLURL() + "/src/branch/" + util.PathEscapeSegments(pr.HeadBranch)
704}
705