Remove SavePatch and generate patches on the fly (#9302)

* Save patches to temporary files

* Remove SavePatch and generate patches on the fly

* Use ioutil.TempDir

* fixup! Use ioutil.TempDir

* fixup! fixup! Use ioutil.TempDir

* RemoveAll LocalCopyPath() in initIntergrationTest

* Default to status checking on PR creation

* Remove unnecessary set to StatusChecking

* Protect against unable to load repo

* Handle conflicts

* Restore original conflict setting

* In TestPullRequests update status to StatusChecking before running TestPatch

1 files changed, 3 insertions, 184 deletions

diff --git a/models/pull.go b/models/pull.go
index 2bd79202f0..33adc3214f 100644
--- a/models/pull.go
+++ b/models/pull.go
@@ -6,22 +6,16 @@
 package models
 
 import (
-	"bufio"
 	"fmt"
 	"os"
 	"path"
-	"path/filepath"
-	"strconv"
 	"strings"
-	"time"
 
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	api "code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/timeutil"
-
-	"github.com/unknwon/com"
 )
 
 // PullRequestType defines pull request type
@@ -481,125 +475,12 @@ func (pr *PullRequest) SetMerged() (err error) {
 	return nil
 }
 
-// patchConflicts is a list of conflict description from Git.
-var patchConflicts = []string{
-	"patch does not apply",
-	"already exists in working directory",
-	"unrecognized input",
-	"error:",
-}
-
-// TestPatch checks if patch can be merged to base repository without conflict.
-func (pr *PullRequest) TestPatch() error {
-	return pr.testPatch(x)
-}
-
-// testPatch checks if patch can be merged to base repository without conflict.
-func (pr *PullRequest) testPatch(e Engine) (err error) {
-	if pr.BaseRepo == nil {
-		pr.BaseRepo, err = getRepositoryByID(e, pr.BaseRepoID)
-		if err != nil {
-			return fmt.Errorf("GetRepositoryByID: %v", err)
-		}
-	}
-
-	patchPath, err := pr.BaseRepo.patchPath(e, pr.Index)
-	if err != nil {
-		return fmt.Errorf("BaseRepo.PatchPath: %v", err)
-	}
-
-	// Fast fail if patch does not exist, this assumes data is corrupted.
-	if !com.IsFile(patchPath) {
-		log.Trace("PullRequest[%d].testPatch: ignored corrupted data", pr.ID)
-		return nil
-	}
-
-	RepoWorkingPool.CheckIn(com.ToStr(pr.BaseRepoID))
-	defer RepoWorkingPool.CheckOut(com.ToStr(pr.BaseRepoID))
-
-	log.Trace("PullRequest[%d].testPatch (patchPath): %s", pr.ID, patchPath)
-
-	pr.Status = PullRequestStatusChecking
-
-	indexTmpPath := filepath.Join(os.TempDir(), "gitea-"+pr.BaseRepo.Name+"-"+strconv.Itoa(time.Now().Nanosecond()))
-	defer os.Remove(indexTmpPath)
-
-	_, err = git.NewCommand("read-tree", pr.BaseBranch).RunInDirWithEnv("", []string{"GIT_DIR=" + pr.BaseRepo.RepoPath(), "GIT_INDEX_FILE=" + indexTmpPath})
-	if err != nil {
-		return fmt.Errorf("git read-tree --index-output=%s %s: %v", indexTmpPath, pr.BaseBranch, err)
-	}
-
-	prUnit, err := pr.BaseRepo.getUnit(e, UnitTypePullRequests)
-	if err != nil {
-		return err
-	}
-	prConfig := prUnit.PullRequestsConfig()
-
-	args := []string{"apply", "--check", "--cached"}
-	if prConfig.IgnoreWhitespaceConflicts {
-		args = append(args, "--ignore-whitespace")
-	}
-	args = append(args, patchPath)
-	pr.ConflictedFiles = []string{}
-
-	stderrBuilder := new(strings.Builder)
-	err = git.NewCommand(args...).RunInDirTimeoutEnvPipeline(
-		[]string{"GIT_INDEX_FILE=" + indexTmpPath, "GIT_DIR=" + pr.BaseRepo.RepoPath()},
-		-1,
-		"",
-		nil,
-		stderrBuilder)
-	stderr := stderrBuilder.String()
-
-	if err != nil {
-		for i := range patchConflicts {
-			if strings.Contains(stderr, patchConflicts[i]) {
-				log.Trace("PullRequest[%d].testPatch (apply): has conflict: %s", pr.ID, stderr)
-				const prefix = "error: patch failed:"
-				pr.Status = PullRequestStatusConflict
-				pr.ConflictedFiles = make([]string, 0, 5)
-				scanner := bufio.NewScanner(strings.NewReader(stderr))
-				for scanner.Scan() {
-					line := scanner.Text()
-
-					if strings.HasPrefix(line, prefix) {
-						var found bool
-						var filepath = strings.TrimSpace(strings.Split(line[len(prefix):], ":")[0])
-						for _, f := range pr.ConflictedFiles {
-							if f == filepath {
-								found = true
-								break
-							}
-						}
-						if !found {
-							pr.ConflictedFiles = append(pr.ConflictedFiles, filepath)
-						}
-					}
-					// only list 10 conflicted files
-					if len(pr.ConflictedFiles) >= 10 {
-						break
-					}
-				}
-
-				if len(pr.ConflictedFiles) > 0 {
-					log.Trace("Found %d files conflicted: %v", len(pr.ConflictedFiles), pr.ConflictedFiles)
-				}
-
-				return nil
-			}
-		}
-
-		return fmt.Errorf("git apply --check: %v - %s", err, stderr)
-	}
-	return nil
-}
-
 // NewPullRequest creates new pull request with labels for repository.
-func NewPullRequest(repo *Repository, pull *Issue, labelIDs []int64, uuids []string, pr *PullRequest, patch []byte) (err error) {
+func NewPullRequest(repo *Repository, pull *Issue, labelIDs []int64, uuids []string, pr *PullRequest) (err error) {
 	// Retry several times in case INSERT fails due to duplicate key for (repo_id, index); see #7887
 	i := 0
 	for {
-		if err = newPullRequestAttempt(repo, pull, labelIDs, uuids, pr, patch); err == nil {
+		if err = newPullRequestAttempt(repo, pull, labelIDs, uuids, pr); err == nil {
 			return nil
 		}
 		if !IsErrNewIssueInsert(err) {
@@ -613,7 +494,7 @@ func NewPullRequest(repo *Repository, pull *Issue, labelIDs []int64, uuids []str
 	return fmt.Errorf("NewPullRequest: too many errors attempting to insert the new issue. Last error was: %v", err)
 }
 
-func newPullRequestAttempt(repo *Repository, pull *Issue, labelIDs []int64, uuids []string, pr *PullRequest, patch []byte) (err error) {
+func newPullRequestAttempt(repo *Repository, pull *Issue, labelIDs []int64, uuids []string, pr *PullRequest) (err error) {
 	sess := x.NewSession()
 	defer sess.Close()
 	if err = sess.Begin(); err != nil {
@@ -635,20 +516,6 @@ func newPullRequestAttempt(repo *Repository, pull *Issue, labelIDs []int64, uuid
 
 	pr.Index = pull.Index
 	pr.BaseRepo = repo
-	pr.Status = PullRequestStatusChecking
-	if len(patch) > 0 {
-		if err = repo.savePatch(sess, pr.Index, patch); err != nil {
-			return fmt.Errorf("SavePatch: %v", err)
-		}
-
-		if err = pr.testPatch(sess); err != nil {
-			return fmt.Errorf("testPatch: %v", err)
-		}
-	}
-	// No conflict appears after test means mergeable.
-	if pr.Status == PullRequestStatusChecking {
-		pr.Status = PullRequestStatusMergeable
-	}
 
 	pr.IssueID = pull.ID
 	if _, err = sess.Insert(pr); err != nil {
@@ -764,54 +631,6 @@ func (pr *PullRequest) UpdateCols(cols ...string) error {
 	return err
 }
 
-// UpdatePatch generates and saves a new patch.
-func (pr *PullRequest) UpdatePatch() (err error) {
-	if err = pr.GetHeadRepo(); err != nil {
-		return fmt.Errorf("GetHeadRepo: %v", err)
-	} else if pr.HeadRepo == nil {
-		log.Trace("PullRequest[%d].UpdatePatch: ignored corrupted data", pr.ID)
-		return nil
-	}
-
-	if err = pr.GetBaseRepo(); err != nil {
-		return fmt.Errorf("GetBaseRepo: %v", err)
-	}
-
-	headGitRepo, err := git.OpenRepository(pr.HeadRepo.RepoPath())
-	if err != nil {
-		return fmt.Errorf("OpenRepository: %v", err)
-	}
-	defer headGitRepo.Close()
-
-	// Add a temporary remote.
-	tmpRemote := com.ToStr(time.Now().UnixNano())
-	if err = headGitRepo.AddRemote(tmpRemote, RepoPath(pr.BaseRepo.MustOwner().Name, pr.BaseRepo.Name), true); err != nil {
-		return fmt.Errorf("AddRemote: %v", err)
-	}
-	defer func() {
-		if err := headGitRepo.RemoveRemote(tmpRemote); err != nil {
-			log.Error("UpdatePatch: RemoveRemote: %s", err)
-		}
-	}()
-	pr.MergeBase, _, err = headGitRepo.GetMergeBase(tmpRemote, pr.BaseBranch, pr.HeadBranch)
-	if err != nil {
-		return fmt.Errorf("GetMergeBase: %v", err)
-	} else if err = pr.Update(); err != nil {
-		return fmt.Errorf("Update: %v", err)
-	}
-
-	patch, err := headGitRepo.GetPatch(pr.MergeBase, pr.HeadBranch)
-	if err != nil {
-		return fmt.Errorf("GetPatch: %v", err)
-	}
-
-	if err = pr.BaseRepo.SavePatch(pr.Index, patch); err != nil {
-		return fmt.Errorf("BaseRepo.SavePatch: %v", err)
-	}
-
-	return nil
-}
-
 // PushToBaseRepo pushes commits from branches of head repository to
 // corresponding branches of base repository.
 // FIXME: Only push branches that are actually updates?