docs(examples): add example tests for Render function

render_example_test.go

@@ -0,0 +1,211 @@
+package render_test
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/jimeh/go-render"
+)
+
+type User struct {
+	Name  string   `json:"name" yaml:"name" xml:"name"`
+	Age   int      `json:"age" yaml:"age" xml:"age"`
+	Roles []*Role  `json:"roles" yaml:"roles" xml:"roles"`
+	Tags  []string `json:"tags" yaml:"tags" xml:"tags"`
+
+	XMLName xml.Name `json:"-" yaml:"-" xml:"user"`
+}
+
+func (u *User) String() string {
+	return fmt.Sprintf(
+		"%s (%d): %s",
+		u.Name, u.Age, strings.Join(u.Tags, ", "),
+	)
+}
+
+type Role struct {
+	Name string `json:"name" yaml:"name" xml:"name"`
+	Icon string `json:"icon" yaml:"icon" xml:"icon"`
+}
+
+func (r *Role) WriteTo(w io.Writer) (int64, error) {
+	s := fmt.Sprintf("%s (%s)", r.Name, r.Icon)
+	n, err := w.Write([]byte(s))
+
+	return int64(n), err
+}
+
+func ExampleRender_json() {
+	data := &User{
+		Name: "John Doe",
+		Age:  30,
+		Roles: []*Role{
+			{Name: "admin", Icon: "shield"},
+			{Name: "developer", Icon: "keyboard"},
+		},
+		Tags: []string{"golang", "json", "yaml", "toml"},
+	}
+
+	// Render the object to JSON.
+	buf := &bytes.Buffer{}
+	err := render.Render(buf, "json", data)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(buf.String())
+
+	// Output:
+	// {
+	//   "name": "John Doe",
+	//   "age": 30,
+	//   "roles": [
+	//     {
+	//       "name": "admin",
+	//       "icon": "shield"
+	//     },
+	//     {
+	//       "name": "developer",
+	//       "icon": "keyboard"
+	//     }
+	//   ],
+	//   "tags": [
+	//     "golang",
+	//     "json",
+	//     "yaml",
+	//     "toml"
+	//   ]
+	// }
+}
+
+func ExampleRender_yaml() {
+	data := &User{
+		Name: "John Doe",
+		Age:  30,
+		Roles: []*Role{
+			{Name: "admin", Icon: "shield"},
+			{Name: "developer", Icon: "keyboard"},
+		},
+		Tags: []string{"golang", "json", "yaml", "toml"},
+	}
+
+	// Render the object to YAML.
+	buf := &bytes.Buffer{}
+	err := render.Render(buf, "yaml", data)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(buf.String())
+
+	// Output:
+	// name: John Doe
+	// age: 30
+	// roles:
+	//   - name: admin
+	//     icon: shield
+	//   - name: developer
+	//     icon: keyboard
+	// tags:
+	//   - golang
+	//   - json
+	//   - yaml
+	//   - toml
+}
+
+func ExampleRender_xml() {
+	data := &User{
+		Name: "John Doe",
+		Age:  30,
+		Roles: []*Role{
+			{Name: "admin", Icon: "shield"},
+			{Name: "developer", Icon: "keyboard"},
+		},
+		Tags: []string{"golang", "json", "yaml", "toml"},
+	}
+
+	// Render the object to XML.
+	buf := &bytes.Buffer{}
+	err := render.Render(buf, "xml", data)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(buf.String())
+
+	// Output:
+	// <user>
+	//   <name>John Doe</name>
+	//   <age>30</age>
+	//   <roles>
+	//     <name>admin</name>
+	//     <icon>shield</icon>
+	//   </roles>
+	//   <roles>
+	//     <name>developer</name>
+	//     <icon>keyboard</icon>
+	//   </roles>
+	//   <tags>golang</tags>
+	//   <tags>json</tags>
+	//   <tags>yaml</tags>
+	//   <tags>toml</tags>
+	// </user>
+}
+
+func ExampleRender_textViaStringer() {
+	// The User struct has a String method which returns a string representation
+	// of a user:
+	//
+	//  func (u *User) String() string {
+	//		return fmt.Sprintf(
+	//			"%s (%d): %s",
+	//			u.Name, u.Age, strings.Join(u.Tags, ", "),
+	//		)
+	//  }
+
+	data := &User{
+		Name: "John Doe",
+		Age:  30,
+		Roles: []*Role{
+			{Name: "admin", Icon: "shield"},
+			{Name: "developer", Icon: "keyboard"},
+		},
+		Tags: []string{"golang", "json", "yaml", "toml"},
+	}
+
+	// Render the object to XML.
+	buf := &bytes.Buffer{}
+	err := render.Render(buf, "text", data)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(buf.String())
+
+	// Output:
+	// John Doe (30): golang, json, yaml, toml
+}
+
+func ExampleRender_textViaWriterTo() {
+	// The Role struct has a WriteTo method which writes a string representation
+	// of a role to an io.Writer:
+	//
+	//	func (r *Role) WriteTo(w io.Writer) (int64, error) {
+	//		s := fmt.Sprintf("%s (%s)", r.Name, r.Icon)
+	//		n, err := w.Write([]byte(s))
+	//
+	//		return int64(n), err
+	//	}
+
+	data := &Role{Name: "admin", Icon: "shield"}
+
+	// Render the object to XML.
+	buf := &bytes.Buffer{}
+	err := render.Render(buf, "text", data)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Println(buf.String())
+
+	// Output:
+	// admin (shield)
+}