add: support for append, prepend elements

Readme.md

@@ -133,7 +133,7 @@ html := react.RenderWithStats(react.H1(nil, react.Text("Hello!")))
 // Print rendered nodes and time 
 // <h1>Hello!</h1>
 
-html := react.RenderBytes(react.H1(nil, react.Text("Hello!"))) // render []byte("<h1>Hello!</h1>")
+html := react.RenderToBytes(react.H1(nil, react.Text("Hello!"))) // render []byte("<h1>Hello!</h1>")
 ```
 
 Passing data to context

element.go

@@ -46,3 +46,18 @@ func (e *Element) isVoidElement() bool {
 
 	return false
 }
+
+func (e *Element) Prepend(el *Element) *Element {
+	e.Childs = append([]*Element{el}, e.Childs...)
+	return e
+}
+
+func (e *Element) Append(el *Element) *Element {
+	e.Childs = append(e.Childs, el)
+	return e
+}
+
+func (e *Element) SetProp(prop string, value interface{}) *Element {
+	e.Props[prop] = value
+	return e
+}

render.go

@@ -15,6 +15,13 @@ func RenderWithStats(component *Element, data ...map[string]interface{}) string
 	return str
 }
 
-func RenderBytes(component *Element, data ...map[string]interface{}) []byte {
+func RenderToBytes(component *Element, data ...map[string]interface{}) []byte {
 	return render(component, data...).Bytes()
 }
+
+func RenderToBytesWithStats(component *Element, data ...map[string]interface{}) []byte {
+	r := render(component, data...)
+	bytes := r.Bytes()
+	r.Stats()
+	return bytes
+}

render_test.go

@@ -33,7 +33,7 @@ func TestRender(t *testing.T) {
 	})
 
 	t.Run("it should render to bytes an empty div", func(t *testing.T) {
-		div := RenderBytes(CreateElement("div", nil))
+		div := RenderToBytes(CreateElement("div", nil))
 
 		assert.Equal(t, []byte("<div></div>"), div)
 	})
@@ -126,4 +126,30 @@ func TestRenderElement(t *testing.T) {
 
 		assert.Equal(t, `Sample text &lt;script type=&#34;text/javascript&#34;&gt;alert(&#34;Hi!&#34;);&lt;/script&gt;`, str)
 	})
+
+	t.Run("it should prepend an element correctly", func(t *testing.T) {
+		el := CreateElement("div", Props{
+			"className": "container",
+		})
+
+		el.Prepend(H1(nil, Text("item 1")))
+		el.Prepend(H1(nil, Text("item 2")))
+
+		div := Render(el)
+
+		assert.Equal(t, `<div class="container"><h1>item 2</h1><h1>item 1</h1></div>`, div)
+	})
+
+	t.Run("it should append an element correctly", func(t *testing.T) {
+		el := CreateElement("div", Props{
+			"className": "container",
+		})
+
+		el.Append(H1(nil, Text("item 1")))
+		el.Append(H1(nil, Text("item 2")))
+
+		div := Render(el)
+
+		assert.Equal(t, `<div class="container"><h1>item 1</h1><h1>item 2</h1></div>`, div)
+	})
 }