Add require signed commit for protected branch (#9708)

* Add require signed commit for protected branch

* Fix fmt

* Make editor show if they will be signed

* bugfix

* Add basic merge check and better information for CRUD

* linting comment

* Add descriptors to merge signing

* Slight refactor

* Slight improvement to appearances

* Handle Merge API

* manage CRUD API

* Move error to error.go

* Remove fix to delete.go

* prep for merge

* need to tolerate \r\n in message

* check protected branch before trying to load it

* Apply suggestions from code review

Co-Authored-By: guillep2k <18600385+guillep2k@users.noreply.github.com>

* fix commit-reader

Co-authored-by: guillep2k <18600385+guillep2k@users.noreply.github.com>

modules/repofiles/delete.go

@@ -55,9 +55,26 @@ func DeleteRepoFile(repo *models.Repository, doer *models.User, opts *DeleteRepo
 				BranchName: opts.NewBranch,
 			}
 		}
-	} else if protected, _ := repo.IsProtectedBranchForPush(opts.OldBranch, doer); protected {
-		return nil, models.ErrUserCannotCommit{
-			UserName: doer.LowerName,
+	} else {
+		protectedBranch, err := repo.GetBranchProtection(opts.OldBranch)
+		if err != nil {
+			return nil, err
+		}
+		if protectedBranch != nil && !protectedBranch.CanUserPush(doer.ID) {
+			return nil, models.ErrUserCannotCommit{
+				UserName: doer.LowerName,
+			}
+		}
+		if protectedBranch != nil && protectedBranch.RequireSignedCommits {
+			_, _, err := repo.SignCRUDAction(doer, repo.RepoPath(), opts.OldBranch)
+			if err != nil {
+				if !models.IsErrWontSign(err) {
+					return nil, err
+				}
+				return nil, models.ErrUserCannotCommit{
+					UserName: doer.LowerName,
+				}
+			}
 		}
 	}