autofix: fix check for empty string (#6804)

Co-authored-by: deepsource-autofix[bot] <62050782+deepsource-autofix[bot]@users.noreply.github.com>

39 files changed, 82 insertions, 86 deletions

diff --git a/internal/auth/ldap/config.go b/internal/auth/ldap/config.go
index 155d161a..db666cde 100644
--- a/internal/auth/ldap/config.go
+++ b/internal/auth/ldap/config.go
@@ -193,7 +193,7 @@ func bindUser(l *ldap.Conn, userDN, passwd string) error {
 // searchEntry searches an LDAP source if an entry (name, passwd) is valid and in the specific filter.
 func (c *Config) searchEntry(name, passwd string, directBind bool) (string, string, string, string, bool, bool) {
 	// See https://tools.ietf.org/search/rfc4513#section-5.1.2
-	if len(passwd) == 0 {
+	if passwd == "" {
 		log.Trace("authentication failed for '%s' with empty password", name)
 		return "", "", "", "", false, false
 	}
diff --git a/internal/auth/ldap/provider.go b/internal/auth/ldap/provider.go
index a42baa71..9cceed47 100644
--- a/internal/auth/ldap/provider.go
+++ b/internal/auth/ldap/provider.go
@@ -32,10 +32,10 @@ func (p *Provider) Authenticate(login, password string) (*auth.ExternalAccount,
 		return nil, auth.ErrBadCredentials{Args: map[string]interface{}{"login": login}}
 	}
 
-	if len(username) == 0 {
+	if username == "" {
 		username = login
 	}
-	if len(email) == 0 {
+	if email == "" {
 		email = fmt.Sprintf("%s@localhost", username)
 	}
 
diff --git a/internal/cmd/hook.go b/internal/cmd/hook.go
index 99a5e15b..b58db829 100644
--- a/internal/cmd/hook.go
+++ b/internal/cmd/hook.go
@@ -63,7 +63,7 @@ var (
 )
 
 func runHookPreReceive(c *cli.Context) error {
-	if len(os.Getenv("SSH_ORIGINAL_COMMAND")) == 0 {
+	if os.Getenv("SSH_ORIGINAL_COMMAND") == "" {
 		return nil
 	}
 	setup(c, "pre-receive.log", true)
@@ -156,7 +156,7 @@ func runHookPreReceive(c *cli.Context) error {
 }
 
 func runHookUpdate(c *cli.Context) error {
-	if len(os.Getenv("SSH_ORIGINAL_COMMAND")) == 0 {
+	if os.Getenv("SSH_ORIGINAL_COMMAND") == "" {
 		return nil
 	}
 	setup(c, "update.log", false)
@@ -164,7 +164,7 @@ func runHookUpdate(c *cli.Context) error {
 	args := c.Args()
 	if len(args) != 3 {
 		fail("Arguments received are not equal to three", "Arguments received are not equal to three")
-	} else if len(args[0]) == 0 {
+	} else if args[0] == "" {
 		fail("First argument 'refName' is empty", "First argument 'refName' is empty")
 	}
 
@@ -190,7 +190,7 @@ func runHookUpdate(c *cli.Context) error {
 }
 
 func runHookPostReceive(c *cli.Context) error {
-	if len(os.Getenv("SSH_ORIGINAL_COMMAND")) == 0 {
+	if os.Getenv("SSH_ORIGINAL_COMMAND") == "" {
 		return nil
 	}
 	setup(c, "post-receive.log", true)
diff --git a/internal/cmd/serv.go b/internal/cmd/serv.go
index 1f9ef044..8f54be82 100644
--- a/internal/cmd/serv.go
+++ b/internal/cmd/serv.go
@@ -125,13 +125,11 @@ func checkDeployKey(key *db.PublicKey, repo *db.Repository) {
 	}
 }
 
-var (
-	allowedCommands = map[string]db.AccessMode{
-		"git-upload-pack":    db.AccessModeRead,
-		"git-upload-archive": db.AccessModeRead,
-		"git-receive-pack":   db.AccessModeWrite,
-	}
-)
+var allowedCommands = map[string]db.AccessMode{
+	"git-upload-pack":    db.AccessModeRead,
+	"git-upload-archive": db.AccessModeRead,
+	"git-receive-pack":   db.AccessModeWrite,
+}
 
 func runServ(c *cli.Context) error {
 	setup(c, "serv.log", true)
@@ -146,7 +144,7 @@ func runServ(c *cli.Context) error {
 	}
 
 	sshCmd := os.Getenv("SSH_ORIGINAL_COMMAND")
-	if len(sshCmd) == 0 {
+	if sshCmd == "" {
 		println("Hi there, You've successfully authenticated, but Gogs does not provide shell access.")
 		println("If this is unexpected, please log in with password and setup Gogs under another user.")
 		return nil
diff --git a/internal/context/auth.go b/internal/context/auth.go
index 6e67d8ef..5f64161a 100644
--- a/internal/context/auth.go
+++ b/internal/context/auth.go
@@ -117,7 +117,7 @@ func authenticatedUserID(c *macaron.Context, sess session.Store) (_ int64, isTok
 		if len(tokenSHA) <= 0 {
 			tokenSHA = c.Query("access_token")
 		}
-		if len(tokenSHA) == 0 {
+		if tokenSHA == "" {
 			// Well, check with header again.
 			auHead := c.Req.Header.Get("Authorization")
 			if len(auHead) > 0 {
diff --git a/internal/context/repo.go b/internal/context/repo.go
index 01759212..f7eca673 100644
--- a/internal/context/repo.go
+++ b/internal/context/repo.go
@@ -284,7 +284,7 @@ func RepoAssignment(pages ...bool) macaron.Handler {
 
 		// If not branch selected, try default one.
 		// If default branch doesn't exists, fall back to some other branch.
-		if len(c.Repo.BranchName) == 0 {
+		if c.Repo.BranchName == "" {
 			if len(c.Repo.Repository.DefaultBranch) > 0 && gitRepo.HasBranch(c.Repo.Repository.DefaultBranch) {
 				c.Repo.BranchName = c.Repo.Repository.DefaultBranch
 			} else if len(branches) > 0 {
@@ -322,7 +322,7 @@ func RepoRef() macaron.Handler {
 		}
 
 		// Get default branch.
-		if len(c.Params("*")) == 0 {
+		if c.Params("*") == "" {
 			refName = c.Repo.Repository.DefaultBranch
 			if !c.Repo.GitRepo.HasBranch(refName) {
 				branches, err := c.Repo.GitRepo.Branches()
diff --git a/internal/db/action.go b/internal/db/action.go
index a9efeeb8..970ff203 100644
--- a/internal/db/action.go
+++ b/internal/db/action.go
@@ -325,7 +325,7 @@ func UpdateIssuesCommit(doer *User, repo *Repository, commits []*PushCommit) err
 			ref = strings.TrimSpace(ref)
 			ref = strings.TrimRightFunc(ref, issueIndexTrimRight)
 
-			if len(ref) == 0 {
+			if ref == "" {
 				continue
 			}
 
@@ -368,7 +368,7 @@ func UpdateIssuesCommit(doer *User, repo *Repository, commits []*PushCommit) err
 			ref = ref[strings.IndexByte(ref, byte(' '))+1:]
 			ref = strings.TrimRightFunc(ref, issueIndexTrimRight)
 
-			if len(ref) == 0 {
+			if ref == "" {
 				continue
 			}
 
@@ -407,7 +407,7 @@ func UpdateIssuesCommit(doer *User, repo *Repository, commits []*PushCommit) err
 			ref = ref[strings.IndexByte(ref, byte(' '))+1:]
 			ref = strings.TrimRightFunc(ref, issueIndexTrimRight)
 
-			if len(ref) == 0 {
+			if ref == "" {
 				continue
 			}
 
diff --git a/internal/db/comment.go b/internal/db/comment.go
index 50976357..b5b982bd 100644
--- a/internal/db/comment.go
+++ b/internal/db/comment.go
@@ -364,7 +364,7 @@ func CreateIssueComment(doer *User, repo *Repository, issue *Issue, content stri
 
 // CreateRefComment creates a commit reference comment to issue.
 func CreateRefComment(doer *User, repo *Repository, issue *Issue, content, commitSHA string) error {
-	if len(commitSHA) == 0 {
+	if commitSHA == "" {
 		return fmt.Errorf("cannot create reference with empty commit SHA")
 	}
 
diff --git a/internal/db/issue_label.go b/internal/db/issue_label.go
index 46e8a62c..f7fdf6a6 100644
--- a/internal/db/issue_label.go
+++ b/internal/db/issue_label.go
@@ -33,7 +33,7 @@ func GetLabelTemplateFile(name string) ([][2]string, error) {
 	list := make([][2]string, 0, len(lines))
 	for i := 0; i < len(lines); i++ {
 		line := strings.TrimSpace(lines[i])
-		if len(line) == 0 {
+		if line == "" {
 			continue
 		}
 
diff --git a/internal/db/org.go b/internal/db/org.go
index 88ad0236..cf984f14 100644
--- a/internal/db/org.go
+++ b/internal/db/org.go
@@ -16,9 +16,7 @@ import (
 	"gogs.io/gogs/internal/errutil"
 )
 
-var (
-	ErrOrgNotExist = errors.New("Organization does not exist")
-)
+var ErrOrgNotExist = errors.New("Organization does not exist")
 
 // IsOwnedBy returns true if given user is in the owner team.
 func (org *User) IsOwnedBy(userID int64) bool {
@@ -174,7 +172,7 @@ func CreateOrganization(org, owner *User) (err error) {
 
 // GetOrgByName returns organization by given name.
 func GetOrgByName(name string) (*User, error) {
-	if len(name) == 0 {
+	if name == "" {
 		return nil, ErrOrgNotExist
 	}
 	u := &User{
diff --git a/internal/db/org_team.go b/internal/db/org_team.go
index 216aa0e9..6bdf4253 100644
--- a/internal/db/org_team.go
+++ b/internal/db/org_team.go
@@ -255,7 +255,7 @@ func IsUsableTeamName(name string) error {
 // NewTeam creates a record of new team.
 // It's caller's responsibility to assign organization ID.
 func NewTeam(t *Team) error {
-	if len(t.Name) == 0 {
+	if t.Name == "" {
 		return errors.New("empty team name")
 	} else if t.OrgID == 0 {
 		return errors.New("OrgID is not assigned")
@@ -364,7 +364,7 @@ func GetTeamsByOrgID(orgID int64) ([]*Team, error) {
 
 // UpdateTeam updates information of team.
 func UpdateTeam(t *Team, authChanged bool) (err error) {
-	if len(t.Name) == 0 {
+	if t.Name == "" {
 		return errors.New("empty team name")
 	}
 
diff --git a/internal/db/release.go b/internal/db/release.go
index e38dc8b1..34f65a20 100644
--- a/internal/db/release.go
+++ b/internal/db/release.go
@@ -109,7 +109,7 @@ func (r *Release) APIFormat() *api.Release {
 
 // IsReleaseExist returns true if release with given tag name already exists.
 func IsReleaseExist(repoID int64, tagName string) (bool, error) {
-	if len(tagName) == 0 {
+	if tagName == "" {
 		return false, nil
 	}
 
diff --git a/internal/db/repo.go b/internal/db/repo.go
index c858f2eb..083989a9 100644
--- a/internal/db/repo.go
+++ b/internal/db/repo.go
@@ -217,7 +217,7 @@ func (repo *Repository) AfterSet(colName string, _ xorm.Cell) {
 	switch colName {
 	case "default_branch":
 		// FIXME: use db migration to solve all at once.
-		if len(repo.DefaultBranch) == 0 {
+		if repo.DefaultBranch == "" {
 			repo.DefaultBranch = "master"
 		}
 	case "num_closed_issues":
@@ -227,7 +227,7 @@ func (repo *Repository) AfterSet(colName string, _ xorm.Cell) {
 	case "num_closed_milestones":
 		repo.NumOpenMilestones = repo.NumMilestones - repo.NumClosedMilestones
 	case "external_tracker_style":
-		if len(repo.ExternalTrackerStyle) == 0 {
+		if repo.ExternalTrackerStyle == "" {
 			repo.ExternalTrackerStyle = markup.IssueNameStyleNumeric
 		}
 	case "created_unix":
diff --git a/internal/db/ssh_key.go b/internal/db/ssh_key.go
index 2f783a9f..f1fc04aa 100644
--- a/internal/db/ssh_key.go
+++ b/internal/db/ssh_key.go
@@ -147,7 +147,7 @@ func parseKeyString(content string) (string, error) {
 		if err != nil {
 			return "", fmt.Errorf("extractTypeFromBase64Key: %v", err)
 		}
-		if len(keyType) == 0 {
+		if keyType == "" {
 			keyType = t
 		} else if keyType != t {
 			return "", fmt.Errorf("key type and content does not match: %s - %s", keyType, t)
diff --git a/internal/db/user.go b/internal/db/user.go
index 3ebaabff..d5d2d60f 100644
--- a/internal/db/user.go
+++ b/internal/db/user.go
@@ -222,7 +222,7 @@ func (u *User) CustomAvatarPath() string {
 // GenerateRandomAvatar generates a random avatar for user.
 func (u *User) GenerateRandomAvatar() error {
 	seed := u.Email
-	if len(seed) == 0 {
+	if seed == "" {
 		seed = u.Name
 	}
 
@@ -479,7 +479,7 @@ func (u *User) IsMailable() bool {
 // If uid is presented, then check will rule out that one,
 // it is used when update a user name in settings page.
 func IsUserExist(uid int64, name string) (bool, error) {
-	if len(name) == 0 {
+	if name == "" {
 		return false, nil
 	}
 	return x.Where("id != ?", uid).Get(&User{LowerName: strings.ToLower(name)})
@@ -729,7 +729,7 @@ func updateUser(e Engine, u *User) error {
 			return ErrEmailAlreadyUsed{args: errutil.Args{"email": u.Email}}
 		}
 
-		if len(u.AvatarEmail) == 0 {
+		if u.AvatarEmail == "" {
 			u.AvatarEmail = u.Email
 		}
 		u.Avatar = tool.HashEmail(u.AvatarEmail)
@@ -955,7 +955,7 @@ func GetAssigneeByID(repo *Repository, userID int64) (*User, error) {
 // GetUserByName returns a user by given name.
 // Deprecated: Use Users.GetByUsername instead.
 func GetUserByName(name string) (*User, error) {
-	if len(name) == 0 {
+	if name == "" {
 		return nil, ErrUserNotExist{args: map[string]interface{}{"name": name}}
 	}
 	u := &User{LowerName: strings.ToLower(name)}
@@ -1035,7 +1035,7 @@ func ValidateCommitsWithEmails(oldCommits []*git.Commit) []*UserCommit {
 // GetUserByEmail returns the user object by given e-mail if exists.
 // Deprecated: Use Users.GetByEmail instead.
 func GetUserByEmail(email string) (*User, error) {
-	if len(email) == 0 {
+	if email == "" {
 		return nil, ErrUserNotExist{args: map[string]interface{}{"email": email}}
 	}
 
@@ -1074,7 +1074,7 @@ type SearchUserOptions struct {
 // SearchUserByName takes keyword and part of user name to search,
 // it returns results in given range and number of total results.
 func SearchUserByName(opts *SearchUserOptions) (users []*User, _ int64, _ error) {
-	if len(opts.Keyword) == 0 {
+	if opts.Keyword == "" {
 		return users, 0, nil
 	}
 	opts.Keyword = strings.ToLower(opts.Keyword)
diff --git a/internal/db/user_mail.go b/internal/db/user_mail.go
index 990b4aa1..fc6e1618 100644
--- a/internal/db/user_mail.go
+++ b/internal/db/user_mail.go
@@ -57,7 +57,7 @@ func GetEmailAddresses(uid int64) ([]*EmailAddress, error) {
 }
 
 func isEmailUsed(e Engine, email string) (bool, error) {
-	if len(email) == 0 {
+	if email == "" {
 		return true, nil
 	}
 
diff --git a/internal/db/users.go b/internal/db/users.go
index ebf2af87..096a2702 100644
--- a/internal/db/users.go
+++ b/internal/db/users.go
@@ -278,7 +278,7 @@ func (ErrUserNotExist) NotFound() bool {
 func (db *users) GetByEmail(email string) (*User, error) {
 	email = strings.ToLower(email)
 
-	if len(email) == 0 {
+	if email == "" {
 		return nil, ErrUserNotExist{args: errutil.Args{"email": email}}
 	}
 
diff --git a/internal/db/webhook.go b/internal/db/webhook.go
index 457fa6cb..bca1fb91 100644
--- a/internal/db/webhook.go
+++ b/internal/db/webhook.go
@@ -470,7 +470,7 @@ func (t *HookTask) AfterSet(colName string, _ xorm.Cell) {
 		t.DeliveredString = time.Unix(0, t.Delivered).Format("2006-01-02 15:04:05 MST")
 
 	case "request_content":
-		if len(t.RequestContent) == 0 {
+		if t.RequestContent == "" {
 			return
 		}
 
@@ -480,7 +480,7 @@ func (t *HookTask) AfterSet(colName string, _ xorm.Cell) {
 		}
 
 	case "response_content":
-		if len(t.ResponseContent) == 0 {
+		if t.ResponseContent == "" {
 			return
 		}
 
diff --git a/internal/db/wiki.go b/internal/db/wiki.go
index 5fbb9fb6..f2276b61 100644
--- a/internal/db/wiki.go
+++ b/internal/db/wiki.go
@@ -122,7 +122,7 @@ func (repo *Repository) updateWikiPage(doer *User, oldTitle, title, content, mes
 		return fmt.Errorf("WriteFile: %v", err)
 	}
 
-	if len(message) == 0 {
+	if message == "" {
 		message = "Update page '" + title + "'"
 	}
 	if err = git.RepoAdd(localPath, git.AddOptions{All: true}); err != nil {
diff --git a/internal/email/message.go b/internal/email/message.go
index 587db161..118e9855 100644
--- a/internal/email/message.go
+++ b/internal/email/message.go
@@ -138,7 +138,7 @@ func (s *Sender) Send(from string, to []string, msg io.WriterTo) error {
 
 	if !opts.DisableHELO {
 		hostname := opts.HELOHostname
-		if len(hostname) == 0 {
+		if hostname == "" {
 			hostname, err = os.Hostname()
 			if err != nil {
 				return err
diff --git a/internal/form/form.go b/internal/form/form.go
index e2fe1a1f..db6e040b 100644
--- a/internal/form/form.go
+++ b/internal/form/form.go
@@ -57,7 +57,7 @@ func Assign(form interface{}, data map[string]interface{}) {
 		// Allow ignored fields in the struct
 		if fieldName == "-" {
 			continue
-		} else if len(fieldName) == 0 {
+		} else if fieldName == "" {
 			fieldName = com.ToSnakeCase(field.Name)
 		}
 
@@ -119,7 +119,7 @@ func validate(errs binding.Errors, data map[string]interface{}, f Form, l macaro
 			data["Err_"+field.Name] = true
 
 			trName := field.Tag.Get("locale")
-			if len(trName) == 0 {
+			if trName == "" {
 				trName = l.Tr("form." + field.Name)
 			} else {
 				trName = l.Tr(trName)
diff --git a/internal/httplib/httplib.go b/internal/httplib/httplib.go
index 142eb7c5..f1b35eb3 100644
--- a/internal/httplib/httplib.go
+++ b/internal/httplib/httplib.go
@@ -169,7 +169,7 @@ func (r *Request) Headers() http.Header {
 // Set the protocol version for incoming requests.
 // Client requests always use HTTP/1.1.
 func (r *Request) SetProtocolVersion(vers string) *Request {
-	if len(vers) == 0 {
+	if vers == "" {
 		vers = "HTTP/1.1"
 	}
 
@@ -339,7 +339,7 @@ func (r *Request) getResponse() (*http.Response, error) {
 		Jar:       jar,
 	}
 
-	if len(r.setting.UserAgent) > 0 && len(r.req.Header.Get("User-Agent")) == 0 {
+	if len(r.setting.UserAgent) > 0 && r.req.Header.Get("User-Agent") == "" {
 		r.req.Header.Set("User-Agent", r.setting.UserAgent)
 	}
 
diff --git a/internal/markup/markup.go b/internal/markup/markup.go
index b542f63d..fbcab4f3 100644
--- a/internal/markup/markup.go
+++ b/internal/markup/markup.go
@@ -70,7 +70,7 @@ func FindAllMentions(content string) []string {
 // cutoutVerbosePrefix cutouts URL prefix including sub-path to
 // return a clean unified string of request URL path.
 func cutoutVerbosePrefix(prefix string) string {
-	if len(prefix) == 0 || prefix[0] != '/' {
+	if prefix == "" || prefix[0] != '/' {
 		return prefix
 	}
 	count := 0
@@ -186,7 +186,7 @@ func wrapImgWithLink(urlPrefix string, buf *bytes.Buffer, token html.Token) {
 	}
 
 	// Skip in case the "src" is empty
-	if len(src) == 0 {
+	if src == "" {
 		buf.WriteString(token.String())
 		return
 	}
diff --git a/internal/route/admin/repos.go b/internal/route/admin/repos.go
index 12560b02..c2d2509c 100644
--- a/internal/route/admin/repos.go
+++ b/internal/route/admin/repos.go
@@ -34,7 +34,7 @@ func Repos(c *context.Context) {
 	)
 
 	keyword := c.Query("q")
-	if len(keyword) == 0 {
+	if keyword == "" {
 		repos, err = db.Repositories(page, conf.UI.Admin.RepoPagingNum)
 		if err != nil {
 			c.Error(err, "list repositories")
diff --git a/internal/route/api/v1/misc/markdown.go b/internal/route/api/v1/misc/markdown.go
index be92a164..0cbfa759 100644
--- a/internal/route/api/v1/misc/markdown.go
+++ b/internal/route/api/v1/misc/markdown.go
@@ -12,7 +12,7 @@ import (
 )
 
 func Markdown(c *context.APIContext, form api.MarkdownOption) {
-	if len(form.Text) == 0 {
+	if form.Text == "" {
 		_, _ = c.Write([]byte(""))
 		return
 	}
diff --git a/internal/route/api/v1/repo/issue.go b/internal/route/api/v1/repo/issue.go
index 8a9f4b77..8d54fd35 100644
--- a/internal/route/api/v1/repo/issue.go
+++ b/internal/route/api/v1/repo/issue.go
@@ -142,7 +142,7 @@ func EditIssue(c *context.APIContext, form api.EditIssueOption) {
 
 	if c.Repo.IsWriter() && form.Assignee != nil &&
 		(issue.Assignee == nil || issue.Assignee.LowerName != strings.ToLower(*form.Assignee)) {
-		if len(*form.Assignee) == 0 {
+		if *form.Assignee == "" {
 			issue.AssigneeID = 0
 		} else {
 			assignee, err := db.GetUserByName(*form.Assignee)
diff --git a/internal/route/home.go b/internal/route/home.go
index d040b957..b1e2cc7a 100644
--- a/internal/route/home.go
+++ b/internal/route/home.go
@@ -38,7 +38,7 @@ func Home(c *context.Context) {
 
 	// Check auto-login.
 	uname := c.GetCookie(conf.Security.CookieUsername)
-	if len(uname) != 0 {
+	if uname != "" {
 		c.Redirect(conf.Server.Subpath + "/user/login")
 		return
 	}
@@ -104,7 +104,7 @@ func RenderUserSearch(c *context.Context, opts *UserSearchOptions) {
 	)
 
 	keyword := c.Query("q")
-	if len(keyword) == 0 {
+	if keyword == "" {
 		users, err = opts.Ranger(page, opts.PageSize)
 		if err != nil {
 			c.Error(err, "ranger")
diff --git a/internal/route/install.go b/internal/route/install.go
index 6e73976a..94c7dd2c 100644
--- a/internal/route/install.go
+++ b/internal/route/install.go
@@ -221,7 +221,7 @@ func InstallPost(c *context.Context, f form.Install) {
 	conf.Database.SSLMode = f.SSLMode
 	conf.Database.Path = f.DbPath
 
-	if conf.Database.Type == "sqlite3" && len(conf.Database.Path) == 0 {
+	if conf.Database.Type == "sqlite3" && conf.Database.Path == "" {
 		c.FormErr("DbPath")
 		c.RenderWithErr(c.Tr("install.err_empty_db_path"), INSTALL, &f)
 		return
@@ -280,14 +280,14 @@ func InstallPost(c *context.Context, f form.Install) {
 	}
 
 	// Check logic loophole between disable self-registration and no admin account.
-	if f.DisableRegistration && len(f.AdminName) == 0 {
+	if f.DisableRegistration && f.AdminName == "" {
 		c.FormErr("Services", "Admin")
 		c.RenderWithErr(c.Tr("install.no_admin_and_disable_registration"), INSTALL, f)
 		return
 	}
 
 	// Check admin password.
-	if len(f.AdminName) > 0 && len(f.AdminPasswd) == 0 {
+	if len(f.AdminName) > 0 && f.AdminPasswd == "" {
 		c.FormErr("Admin", "AdminPasswd")
 		c.RenderWithErr(c.Tr("install.err_empty_admin_password"), INSTALL, f)
 		return
diff --git a/internal/route/repo/commit.go b/internal/route/repo/commit.go
index ae424d06..3e09bd06 100644
--- a/internal/route/repo/commit.go
+++ b/internal/route/repo/commit.go
@@ -25,7 +25,7 @@ const (
 func RefCommits(c *context.Context) {
 	c.Data["PageIsViewFiles"] = true
 	switch {
-	case len(c.Repo.TreePath) == 0:
+	case c.Repo.TreePath == "":
 		Commits(c)
 	case c.Repo.TreePath == "search":
 		SearchCommits(c)
@@ -85,7 +85,7 @@ func SearchCommits(c *context.Context) {
 	c.Data["PageIsCommits"] = true
 
 	keyword := c.Query("q")
-	if len(keyword) == 0 {
+	if keyword == "" {
 		c.Redirect(c.Repo.RepoLink + "/commits/" + c.Repo.BranchName)
 		return
 	}
diff --git a/internal/route/repo/editor.go b/internal/route/repo/editor.go
index 6556187e..8f612a98 100644
--- a/internal/route/repo/editor.go
+++ b/internal/route/repo/editor.go
@@ -33,7 +33,7 @@ const (
 // getParentTreeFields returns list of parent tree names and corresponding tree paths
 // based on given tree path.
 func getParentTreeFields(treePath string) (treeNames, treePaths []string) {
-	if len(treePath) == 0 {
+	if treePath == "" {
 		return treeNames, treePaths
 	}
 
@@ -158,7 +158,7 @@ func editFilePost(c *context.Context, f form.EditRepoFile, isNewFile bool) {
 		return
 	}
 
-	if len(f.TreePath) == 0 {
+	if f.TreePath == "" {
 		c.FormErr("TreePath")
 		c.RenderWithErr(c.Tr("repo.editor.filename_cannot_be_empty"), tmplEditorEdit, &f)
 		return
@@ -248,7 +248,7 @@ func editFilePost(c *context.Context, f form.EditRepoFile, isNewFile bool) {
 	}
 
 	message := strings.TrimSpace(f.CommitSummary)
-	if len(message) == 0 {
+	if message == "" {
 		if isNewFile {
 			message = c.Tr("repo.editor.add", f.TreePath)
 		} else {
@@ -362,7 +362,7 @@ func DeleteFilePost(c *context.Context, f form.DeleteRepoFile) {
 	}
 
 	message := strings.TrimSpace(f.CommitSummary)
-	if len(message) == 0 {
+	if message == "" {
 		message = c.Tr("repo.editor.delete", c.Repo.TreePath)
 	}
 
@@ -481,7 +481,7 @@ func UploadFilePost(c *context.Context, f form.UploadRepoFile) {
 	}
 
 	message := strings.TrimSpace(f.CommitSummary)
-	if len(message) == 0 {
+	if message == "" {
 		message = c.Tr("repo.editor.upload_files_to_dir", f.TreePath)
 	}
 
@@ -555,7 +555,7 @@ func UploadFileToServer(c *context.Context) {
 }
 
 func RemoveUploadFileFromServer(c *context.Context, f form.RemoveUploadFile) {
-	if len(f.File) == 0 {
+	if f.File == "" {
 		c.Status(http.StatusNoContent)
 		return
 	}
diff --git a/internal/route/repo/http.go b/internal/route/repo/http.go
index e14569f1..67d8edf8 100644
--- a/internal/route/repo/http.go
+++ b/internal/route/repo/http.go
@@ -106,7 +106,7 @@ func HTTPContexter() macaron.Handler {
 
 		// Handle HTTP Basic Authentication
 		authHead := c.Req.Header.Get("Authorization")
-		if len(authHead) == 0 {
+		if authHead == "" {
 			askCredentials(c, http.StatusUnauthorized, "")
 			return
 		}
diff --git a/internal/route/repo/issue.go b/internal/route/repo/issue.go
index 1b64cfe2..5caa16cb 100644
--- a/internal/route/repo/issue.go
+++ b/internal/route/repo/issue.go
@@ -700,7 +700,7 @@ func UpdateIssueTitle(c *context.Context) {
 	}
 
 	title := c.QueryTrim("title")
-	if len(title) == 0 {
+	if title == "" {
 		c.Status(http.StatusNoContent)
 		return
 	}
@@ -903,7 +903,7 @@ func NewComment(c *context.Context, f form.CreateComment) {
 	}()
 
 	// Fix #321: Allow empty comments, as long as we have attachments.
-	if len(f.Content) == 0 && len(attachments) == 0 {
+	if f.Content == "" && len(attachments) == 0 {
 		return
 	}
 
@@ -933,7 +933,7 @@ func UpdateCommentContent(c *context.Context) {
 
 	oldContent := comment.Content
 	comment.Content = c.Query("content")
-	if len(comment.Content) == 0 {
+	if comment.Content == "" {
 		c.JSONSuccess(map[string]interface{}{
 			"content": "",
 		})
@@ -1127,7 +1127,7 @@ func NewMilestonePost(c *context.Context, f form.CreateMilestone) {
 		return
 	}
 
-	if len(f.Deadline) == 0 {
+	if f.Deadline == "" {
 		f.Deadline = "9999-12-31"
 	}
 	deadline, err := time.ParseInLocation("2006-01-02", f.Deadline, time.Local)
@@ -1183,7 +1183,7 @@ func EditMilestonePost(c *context.Context, f form.CreateMilestone) {
 		return
 	}
 
-	if len(f.Deadline) == 0 {
+	if f.Deadline == "" {
 		f.Deadline = "9999-12-31"
 	}
 	deadline, err := time.ParseInLocation("2006-01-02", f.Deadline, time.Local)
diff --git a/internal/route/repo/release.go b/internal/route/repo/release.go
index 1b3de8a5..f8a90f42 100644
--- a/internal/route/repo/release.go
+++ b/internal/route/repo/release.go
@@ -293,7 +293,7 @@ func EditReleasePost(c *context.Context, f form.EditRelease) {
 		attachments = f.Files
 	}
 
-	isPublish := rel.IsDraft && len(f.Draft) == 0
+	isPublish := rel.IsDraft && f.Draft == ""
 	rel.Title = f.Title
 	rel.Note = f.Content
 	rel.IsDraft = len(f.Draft) > 0
diff --git a/internal/route/repo/setting.go b/internal/route/repo/setting.go
index dcbf520c..3df230ea 100644
--- a/internal/route/repo/setting.go
+++ b/internal/route/repo/setting.go
@@ -378,7 +378,7 @@ func SettingsCollaboration(c *context.Context) {
 
 func SettingsCollaborationPost(c *context.Context) {
 	name := strings.ToLower(c.Query("collaborator"))
-	if len(name) == 0 || c.Repo.Owner.LowerName == name {
+	if name == "" || c.Repo.Owner.LowerName == name {
 		c.Redirect(conf.Server.Subpath + c.Req.URL.Path)
 		return
 	}
diff --git a/internal/route/repo/view.go b/internal/route/repo/view.go
index f105ad65..e9f340cb 100644
--- a/internal/route/repo/view.go
+++ b/internal/route/repo/view.go
@@ -177,7 +177,7 @@ func renderFile(c *context.Context, entry *git.TreeEntry, treeLink, rawLink stri
 			var output bytes.Buffer
 			lines := strings.Split(fileContent, "\n")
 			// Remove blank line at the end of file
-			if len(lines) > 0 && len(lines[len(lines)-1]) == 0 {
+			if len(lines) > 0 && lines[len(lines)-1] == "" {
 				lines = lines[:len(lines)-1]
 			}
 			for index, line := range lines {
diff --git a/internal/route/repo/wiki.go b/internal/route/repo/wiki.go
index b9f754ee..70c82626 100644
--- a/internal/route/repo/wiki.go
+++ b/internal/route/repo/wiki.go
@@ -75,7 +75,7 @@ func renderWikiPage(c *context.Context, isViewPage bool) (*git.Repository, strin
 	}
 
 	pageURL := c.Params(":page")
-	if len(pageURL) == 0 {
+	if pageURL == "" {
 		pageURL = "Home"
 	}
 	c.Data["PageURL"] = pageURL
@@ -253,7 +253,7 @@ func EditWikiPost(c *context.Context, f form.NewWiki) {
 
 func DeleteWikiPagePost(c *context.Context) {
 	pageURL := c.Params(":page")
-	if len(pageURL) == 0 {
+	if pageURL == "" {
 		pageURL = "Home"
 	}
 
diff --git a/internal/route/user/auth.go b/internal/route/user/auth.go
index 26eb7d4b..87e23b4b 100644
--- a/internal/route/user/auth.go
+++ b/internal/route/user/auth.go
@@ -38,7 +38,7 @@ func AutoLogin(c *context.Context) (bool, error) {
 	}
 
 	uname := c.GetCookie(conf.Security.CookieUsername)
-	if len(uname) == 0 {
+	if uname == "" {
 		return false, nil
 	}
 
@@ -384,7 +384,7 @@ func SignUpPost(c *context.Context, cpt *captcha.Captcha, f form.Register) {
 
 func Activate(c *context.Context) {
 	code := c.Query("code")
-	if len(code) == 0 {
+	if code == "" {
 		c.Data["IsActivatePage"] = true
 		if c.User.IsActive {
 			c.NotFound()
@@ -515,7 +515,7 @@ func ResetPasswd(c *context.Context) {
 	c.Title("auth.reset_password")
 
 	code := c.Query("code")
-	if len(code) == 0 {
+	if code == "" {
 		c.NotFound()
 		return
 	}
@@ -528,7 +528,7 @@ func ResetPasswdPost(c *context.Context) {
 	c.Title("auth.reset_password")
 
 	code := c.Query("code")
-	if len(code) == 0 {
+	if code == "" {
 		c.NotFound()
 		return
 	}
diff --git a/internal/template/template.go b/internal/template/template.go
index e904e6e9..dcb56639 100644
--- a/internal/template/template.go
+++ b/internal/template/template.go
@@ -93,7 +93,7 @@ func FuncMap() []template.FuncMap {
 				return t.Format("Jan 02, 2006")
 			},
 			"SubStr": func(str string, start, length int) string {
-				if len(str) == 0 {
+				if str == "" {
 					return ""
 				}
 				end := start + length
@@ -186,7 +186,7 @@ func RenderCommitMessage(full bool, msg, urlPrefix string, metas map[string]stri
 		return ""
 	} else if !full {
 		return msgLines[0]
-	} else if numLines == 1 || (numLines >= 2 && len(msgLines[1]) == 0) {
+	} else if numLines == 1 || (numLines >= 2 && msgLines[1] == "") {
 		// First line is a header, standalone or followed by empty line
 		header := fmt.Sprintf("<h3>%s</h3>", msgLines[0])
 		if numLines >= 2 {
diff --git a/internal/tool/tool.go b/internal/tool/tool.go
index d2110919..9dc7e104 100644
--- a/internal/tool/tool.go
+++ b/internal/tool/tool.go
@@ -143,10 +143,10 @@ func AvatarLink(email string) (url string) {
 			log.Warn("AvatarLink.LibravatarService.FromEmail [%s]: %v", email, err)
 		}
 	}
-	if len(url) == 0 && !conf.Picture.DisableGravatar {
+	if url == "" && !conf.Picture.DisableGravatar {
 		url = conf.Picture.GravatarSource + HashEmail(email) + "?d=identicon"
 	}
-	if len(url) == 0 {
+	if url == "" {
 		url = conf.Server.Subpath + "/img/avatar_default.png"
 	}
 	return url