🔥 Add Global ViewLayout (#1384)

* Add Global Layout for view render

* Add test case for Views Layout

* Update ctx_test.go

.github/testdata/main.tmpl

@@ -0,0 +1 @@
+<h1>I'm main</h1>

app.go

@@ -174,6 +174,11 @@ type Config struct {
 	// Default: nil
 	Views Views `json:"-"`
 
+	// Views Layout is the global layout for all template render until override on Render function.
+	//
+	// Default: ""
+	ViewsLayout string `json:"views_layout"`
+
 	// The amount of time allowed to read the full request including body.
 	// It is reset after the request handler has returned.
 	// The connection's read deadline is reset when the connection opens.

ctx.go

@@ -888,6 +888,12 @@ func (c *Ctx) Render(name string, bind interface{}, layouts ...string) error {
 	defer bytebufferpool.Put(buf)
 
 	if c.app.config.Views != nil {
+		// Render template based on global layout if exists
+		if len(layouts) == 0 && c.app.config.ViewsLayout != "" {
+			layouts = []string{
+				c.app.config.ViewsLayout,
+			}
+		}
 		// Render template from Views
 		if err := c.app.config.Views.Render(buf, name, bind, layouts...); err != nil {
 			return err

ctx_test.go

@@ -1639,7 +1639,11 @@ type testTemplateEngine struct {
 }
 
 func (t *testTemplateEngine) Render(w io.Writer, name string, bind interface{}, layout ...string) error {
-	return t.templates.ExecuteTemplate(w, name, bind)
+	if len(layout) == 0 {
+		return t.templates.ExecuteTemplate(w, name, bind)
+	}
+	_ = t.templates.ExecuteTemplate(w, name, bind)
+	return t.templates.ExecuteTemplate(w, layout[0], bind)
 }
 
 func (t *testTemplateEngine) Load() error {
@@ -1662,6 +1666,21 @@ func Test_Ctx_Render_Engine(t *testing.T) {
 	utils.AssertEqual(t, "<h1>Hello, World!</h1>", string(c.Response().Body()))
 }
 
+// go test -run Test_Ctx_Render_Engine_With_View_Layout
+func Test_Ctx_Render_Engine_With_View_Layout(t *testing.T) {
+	engine := &testTemplateEngine{}
+	engine.Load()
+	app := New(Config{ViewsLayout: "main.tmpl"})
+	app.config.Views = engine
+	c := app.AcquireCtx(&fasthttp.RequestCtx{})
+	defer app.ReleaseCtx(c)
+	err := c.Render("index.tmpl", Map{
+		"Title": "Hello, World!",
+	})
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, "<h1>Hello, World!</h1><h1>I'm main</h1>", string(c.Response().Body()))
+}
+
 // go test -v -run=^$ -bench=Benchmark_Ctx_Render_Engine -benchmem -count=4
 func Benchmark_Ctx_Render_Engine(b *testing.B) {
 	engine := &testTemplateEngine{}