Add Rawf (#114)

Like `Raw`, but interpolates like `Textf`.

gomponents.go

@@ -4,7 +4,7 @@
 // to the given writer as a string.
 //
 // All DOM elements and attributes can be created by using the El and Attr functions.
-// The functions Text, Textf, and Raw can be used to create text nodes.
+// The functions Text, Textf, Raw, and Rawf can be used to create text nodes.
 // See also helper functions Group, Map, and If.
 //
 // For basic HTML elements and attributes, see the package html.
@@ -207,7 +207,7 @@ func Text(t string) Node {
 	})
 }
 
-// Textf creates a text DOM Node that Renders the interpolated and escaped string t.
+// Textf creates a text DOM Node that Renders the interpolated and escaped string format.
 func Textf(format string, a ...interface{}) Node {
 	return NodeFunc(func(w io.Writer) error {
 		_, err := w.Write([]byte(template.HTMLEscapeString(fmt.Sprintf(format, a...))))
@@ -223,6 +223,14 @@ func Raw(t string) Node {
 	})
 }
 
+// Rawf creates a text DOM Node that just Renders the interpolated and unescaped string format.
+func Rawf(format string, a ...interface{}) Node {
+	return NodeFunc(func(w io.Writer) error {
+		_, err := w.Write([]byte(fmt.Sprintf(format, a...)))
+		return err
+	})
+}
+
 type group struct {
 	children []Node
 }

gomponents_test.go

@@ -212,6 +212,21 @@ func ExampleRaw() {
 	// Output: <span><button onclick="javascript:alert('Party time!')">Party hats</button> &gt; normal hats.</span>
 }
 
+func TestRawf(t *testing.T) {
+	t.Run("renders interpolated and raw text", func(t *testing.T) {
+		e := g.Rawf("<%v>", "div")
+		assert.Equal(t, "<div>", e)
+	})
+}
+
+func ExampleRawf() {
+	e := g.El("span",
+		g.Rawf(`<button onclick="javascript:alert('%v')">Party hats</button> &gt; normal hats.`, "Party time!"),
+	)
+	_ = e.Render(os.Stdout)
+	// Output: <span><button onclick="javascript:alert('Party time!')">Party hats</button> &gt; normal hats.</span>
+}
+
 func TestGroup(t *testing.T) {
 	t.Run("groups multiple nodes into one", func(t *testing.T) {
 		children := []g.Node{g.El("br", g.Attr("id", "hat")), g.El("hr")}