[GITEA] Use existing error functionality

- There's no need to use `github.com/pkg/errors` when the standard
library already has the functionality to wrap and create errors.

(cherry picked from commit 40f603a538036ce7e150adf404374d794eb46993)
(cherry picked from commit aa68a2753f204dfe44a037ccc91dacc2a0a53803)
(cherry picked from commit 48e252d73961ae17b56544bae79bc812dac10c44)
(cherry picked from commit cc6f40ccd208a6fd1527ba08e3123e9b01b218ab)
(cherry picked from commit 03c4b9735824bfaed19df14550ef458d52667b40)
(cherry picked from commit f25eeb76958b78fbe00fc6556aec8a37aba0ecdf)
(cherry picked from commit 989d8fa1cb81e0ff017ac575fdd1cf12507eb42b)

go.mod

@@ -83,7 +83,6 @@ require (
 	github.com/olivere/elastic/v7 v7.0.32
 	github.com/opencontainers/go-digest v1.0.0
 	github.com/opencontainers/image-spec v1.1.0-rc5
-	github.com/pkg/errors v0.9.1
 	github.com/pquerna/otp v1.4.0
 	github.com/prometheus/client_golang v1.17.0
 	github.com/quasoft/websspi v1.1.2
@@ -245,6 +244,7 @@ require (
 	github.com/pelletier/go-toml/v2 v2.1.1 // indirect
 	github.com/pierrec/lz4/v4 v4.1.19 // indirect
 	github.com/pjbgf/sha1cd v0.3.0 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/prometheus/client_model v0.5.0 // indirect
 	github.com/prometheus/common v0.45.0 // indirect

services/pull/commit_status.go

@@ -6,6 +6,8 @@ package pull
 
 import (
 	"context"
+	"errors"
+	"fmt"
 
 	"code.gitea.io/gitea/models/db"
 	git_model "code.gitea.io/gitea/models/git"
@@ -15,7 +17,6 @@ import (
 	"code.gitea.io/gitea/modules/structs"
 
 	"github.com/gobwas/glob"
-	"github.com/pkg/errors"
 )
 
 // MergeRequiredContextsCommitStatus returns a commit status state for given required contexts
@@ -95,7 +96,7 @@ func IsCommitStatusContextSuccess(commitStatuses []*git_model.CommitStatus, requ
 func IsPullCommitStatusPass(ctx context.Context, pr *issues_model.PullRequest) (bool, error) {
 	pb, err := git_model.GetFirstMatchProtectedBranchRule(ctx, pr.BaseRepoID, pr.BaseBranch)
 	if err != nil {
-		return false, errors.Wrap(err, "GetLatestCommitStatus")
+		return false, fmt.Errorf("GetFirstMatchProtectedBranchRule: %w", err)
 	}
 	if pb == nil || !pb.EnableStatusCheck {
 		return true, nil
@@ -112,21 +113,21 @@ func IsPullCommitStatusPass(ctx context.Context, pr *issues_model.PullRequest) (
 func GetPullRequestCommitStatusState(ctx context.Context, pr *issues_model.PullRequest) (structs.CommitStatusState, error) {
 	// Ensure HeadRepo is loaded
 	if err := pr.LoadHeadRepo(ctx); err != nil {
-		return "", errors.Wrap(err, "LoadHeadRepo")
+		return "", fmt.Errorf("LoadHeadRepo: %w", err)
 	}
 
 	// check if all required status checks are successful
 	headGitRepo, closer, err := git.RepositoryFromContextOrOpen(ctx, pr.HeadRepo.RepoPath())
 	if err != nil {
-		return "", errors.Wrap(err, "OpenRepository")
+		return "", fmt.Errorf("RepositoryFromContextOrOpen: %w", err)
 	}
 	defer closer.Close()
 
 	if pr.Flow == issues_model.PullRequestFlowGithub && !headGitRepo.IsBranchExist(pr.HeadBranch) {
-		return "", errors.New("Head branch does not exist, can not merge")
+		return "", errors.New("head branch does not exist, can not merge")
 	}
 	if pr.Flow == issues_model.PullRequestFlowAGit && !git.IsReferenceExist(ctx, headGitRepo.Path, pr.GetGitRefName()) {
-		return "", errors.New("Head branch does not exist, can not merge")
+		return "", errors.New("head branch does not exist, can not merge")
 	}
 
 	var sha string
@@ -140,17 +141,17 @@ func GetPullRequestCommitStatusState(ctx context.Context, pr *issues_model.PullR
 	}
 
 	if err := pr.LoadBaseRepo(ctx); err != nil {
-		return "", errors.Wrap(err, "LoadBaseRepo")
+		return "", fmt.Errorf("LoadBaseRepo: %w", err)
 	}
 
 	commitStatuses, _, err := git_model.GetLatestCommitStatus(ctx, pr.BaseRepo.ID, sha, db.ListOptions{ListAll: true})
 	if err != nil {
-		return "", errors.Wrap(err, "GetLatestCommitStatus")
+		return "", fmt.Errorf("GetLatestCommitStatus: %w", err)
 	}
 
 	pb, err := git_model.GetFirstMatchProtectedBranchRule(ctx, pr.BaseRepoID, pr.BaseBranch)
 	if err != nil {
-		return "", errors.Wrap(err, "LoadProtectedBranch")
+		return "", fmt.Errorf("GetFirstMatchProtectedBranchRule: %w", err)
 	}
 	var requiredContexts []string
 	if pb != nil {