Refactor locale&string&template related code (#29165)

Clarify when "string" should be used (and be escaped), and when
"template.HTML" should be used (no need to escape)

And help PRs like  #29059 , to render the error messages correctly.

(cherry picked from commit f3eb835886031df7a562abc123c3f6011c81eca8)

Conflicts:
	modules/web/middleware/binding.go
	routers/web/feed/convert.go
	tests/integration/branches_test.go
	tests/integration/repo_branch_test.go
	trivial context conflicts

modules/context/api.go

@@ -247,7 +247,7 @@ func APIContexter() func(http.Handler) http.Handler {
 // NotFound handles 404s for APIContext
 // String will replace message, errors will be added to a slice
 func (ctx *APIContext) NotFound(objs ...any) {
-	message := ctx.Tr("error.not_found")
+	message := ctx.Locale.TrString("error.not_found")
 	var errors []string
 	for _, obj := range objs {
 		// Ignore nil

modules/context/base.go

@@ -6,6 +6,7 @@ package context
 import (
 	"context"
 	"fmt"
+	"html/template"
 	"io"
 	"net/http"
 	"net/url"
@@ -286,11 +287,11 @@ func (b *Base) cleanUp() {
 	}
 }
 
-func (b *Base) Tr(msg string, args ...any) string {
+func (b *Base) Tr(msg string, args ...any) template.HTML {
 	return b.Locale.Tr(msg, args...)
 }
 
-func (b *Base) TrN(cnt any, key1, keyN string, args ...any) string {
+func (b *Base) TrN(cnt any, key1, keyN string, args ...any) template.HTML {
 	return b.Locale.TrN(cnt, key1, keyN, args...)
 }
 

modules/context/context.go

@@ -6,7 +6,7 @@ package context
 
 import (
 	"context"
-	"html"
+	"fmt"
 	"html/template"
 	"io"
 	"net/http"
@@ -71,16 +71,6 @@ func init() {
 	})
 }
 
-// TrHTMLEscapeArgs runs ".Locale.Tr()" but pre-escapes all arguments with html.EscapeString.
-// This is useful if the locale message is intended to only produce HTML content.
-func (ctx *Context) TrHTMLEscapeArgs(msg string, args ...string) string {
-	trArgs := make([]any, len(args))
-	for i, arg := range args {
-		trArgs[i] = html.EscapeString(arg)
-	}
-	return ctx.Locale.Tr(msg, trArgs...)
-}
-
 type webContextKeyType struct{}
 
 var WebContextKey = webContextKeyType{}
@@ -253,6 +243,13 @@ func (ctx *Context) JSONOK() {
 	ctx.JSON(http.StatusOK, map[string]any{"ok": true}) // this is only a dummy response, frontend seldom uses it
 }
 
-func (ctx *Context) JSONError(msg string) {
-	ctx.JSON(http.StatusBadRequest, map[string]any{"errorMessage": msg})
+func (ctx *Context) JSONError(msg any) {
+	switch v := msg.(type) {
+	case string:
+		ctx.JSON(http.StatusBadRequest, map[string]any{"errorMessage": v, "renderFormat": "text"})
+	case template.HTML:
+		ctx.JSON(http.StatusBadRequest, map[string]any{"errorMessage": v, "renderFormat": "html"})
+	default:
+		panic(fmt.Sprintf("unsupported type: %T", msg))
+	}
 }

modules/context/context_response.go

@@ -98,12 +98,11 @@ func (ctx *Context) RenderToString(name base.TplName, data map[string]any) (stri
 }
 
 // RenderWithErr used for page has form validation but need to prompt error to users.
-func (ctx *Context) RenderWithErr(msg string, tpl base.TplName, form any) {
+func (ctx *Context) RenderWithErr(msg any, tpl base.TplName, form any) {
 	if form != nil {
 		middleware.AssignForm(form, ctx.Data)
 	}
-	ctx.Flash.ErrorMsg = msg
-	ctx.Data["Flash"] = ctx.Flash
+	ctx.Flash.Error(msg, true)
 	ctx.HTML(http.StatusOK, tpl)
 }
 

modules/context/repo.go

@@ -6,6 +6,7 @@ package context
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"html"
 	"net/http"
@@ -110,7 +111,7 @@ func (r *Repository) AllUnitsEnabled(ctx context.Context) bool {
 func RepoMustNotBeArchived() func(ctx *Context) {
 	return func(ctx *Context) {
 		if ctx.Repo.Repository.IsArchived {
-			ctx.NotFound("IsArchived", fmt.Errorf(ctx.Tr("repo.archive.title")))
+			ctx.NotFound("IsArchived", errors.New(ctx.Locale.TrString("repo.archive.title")))
 		}
 	}
 }