chore: form binding trim space (#38978)

Use "binding:TrimSpace" instead of fragile IsEmptyString

And fix a bug in locale's `HasKey`: it should also try the default
language if current language doesn't have the translation key, a new
test is added.

routers/web/admin/auths.go

@@ -18,7 +18,6 @@ import (
 	"gitea.dev/modules/log"
 	"gitea.dev/modules/setting"
 	"gitea.dev/modules/templates"
-	"gitea.dev/modules/util"
 	"gitea.dev/modules/web"
 	auth_service "gitea.dev/services/auth"
 	"gitea.dev/services/auth/source/ldap"
@@ -210,7 +209,7 @@ func parseOAuth2Config(form forms.AuthenticationForm) *oauth2.Source {
 }
 
 func parseSSPIConfig(ctx *context.Context, form forms.AuthenticationForm) (*sspi.Source, error) {
-	if util.IsEmptyString(form.SSPISeparatorReplacement) {
+	if form.SSPISeparatorReplacement == "" {
 		ctx.Data["Err_SSPISeparatorReplacement"] = true
 		return nil, errors.New(ctx.Locale.TrString("form.require_error", ctx.Locale.TrString("form.SSPISeparatorReplacement")))
 	}

routers/web/repo/issue_new.go

@@ -351,11 +351,6 @@ func NewIssuePost(ctx *context.Context) {
 		return
 	}
 
-	if util.IsEmptyString(form.Title) {
-		ctx.JSONError(ctx.Tr("repo.issues.new.title_empty"))
-		return
-	}
-
 	content := form.Content
 	if filename := ctx.Req.Form.Get("template-file"); filename != "" {
 		if template, err := issue_template.UnmarshalFromRepo(ctx, ctx.Repo.GitRepo, ctx.Repo.Repository.DefaultBranch, filename); err == nil {

routers/web/repo/pull.go

@@ -1353,11 +1353,6 @@ func CompareAndPullRequestPost(ctx *context.Context) {
 		return
 	}
 
-	if util.IsEmptyString(form.Title) {
-		ctx.JSONError(ctx.Tr("repo.issues.new.title_empty"))
-		return
-	}
-
 	// Check if a pull request already exists with the same head and base branch.
 	pr, err := issues_model.GetUnmergedPullRequest(ctx, ci.HeadRepo.ID, repo.ID, ci.HeadRef.ShortName(), ci.BaseRef.ShortName(), issues_model.PullRequestFlowGithub)
 	if err != nil && !issues_model.IsErrPullRequestNotExist(err) {