readme: move uuid example to tests

Make example executable by adding reference output to the comments.

Author: ligurio

README.md

@@ -23,7 +23,6 @@ faster than other packages according to public benchmarks.
 * [API reference](#api-reference)
 * [Walking\-through example](#walking-through-example)
 * [Help](#help)
-* [Usage](#usage)
 * [Schema](#schema)
 * [Custom (un)packing and typed selects and function calls](#custom-unpacking-and-typed-selects-and-function-calls)
 * [Options](#options)
@@ -172,52 +171,6 @@ To contact `go-tarantool` developers on any problems, create an issue at
 The developers of the [Tarantool server](http://github.com/tarantool/tarantool)
 will also be happy to provide advice or receive feedback.
 
-## Usage
-
-To enable support of UUID in msgpack with [google/uuid](https://github.com/google/uuid),
-import tarantool/uuid submodule.
-```go
-package main
-
-import (
-	"log"
-	"time"
-
-	"github.com/tarantool/go-tarantool"
-	_ "github.com/tarantool/go-tarantool/uuid"
-	"github.com/google/uuid"
-)
-
-func main() {
-	server := "127.0.0.1:3013"
-	opts := tarantool.Opts{
-		Timeout:       500 * time.Millisecond,
-		Reconnect:     1 * time.Second,
-		MaxReconnects: 3,
-		User:          "test",
-		Pass:          "test",
-	}
-	client, err := tarantool.Connect(server, opts)
-	if err != nil {
-		log.Fatalf("Failed to connect: %s", err.Error())
-	}
-
-	spaceNo := uint32(524)
-
-	id, uuidErr := uuid.Parse("c8f0fa1f-da29-438c-a040-393f1126ad39")
-	if uuidErr != nil {
-		log.Fatalf("Failed to prepare uuid: %s", uuidErr)
-	}
-
-	resp, err := client.Replace(spaceNo, []interface{}{ id })
-
-	log.Println("UUID tuple replace")
-	log.Println("Error", err)
-	log.Println("Code", resp.Code)
-	log.Println("Data", resp.Data)
-}
-```
-
 ## Schema
 
 ```go

uuid/example_test.go

@@ -0,0 +1,55 @@
+// To enable support of UUID in msgpack with
+// [google/uuid](https://github.com/google/uuid), import tarantool/uuid
+// submodule.
+//
+// Run Tarantool instance before example execution:
+// $ cd uuid
+// $ TT_LISTEN=3013 TT_WORK_DIR=$(mktemp -d -t 'tarantool.XXX') tarantool config.lua
+// $ go test -v example_test.go
+//
+package uuid_test
+
+import (
+	"fmt"
+	"log"
+	"time"
+
+	"github.com/google/uuid"
+	"github.com/tarantool/go-tarantool"
+	_ "github.com/tarantool/go-tarantool/uuid"
+)
+
+func Example() {
+	server := "127.0.0.1:3013"
+	opts := tarantool.Opts{
+		Timeout:       500 * time.Millisecond,
+		Reconnect:     1 * time.Second,
+		MaxReconnects: 3,
+		User:          "test",
+		Pass:          "test",
+	}
+	client, err := tarantool.Connect(server, opts)
+	if err != nil {
+		log.Fatalf("Failed to connect: %s", err.Error())
+	}
+
+	spaceNo := uint32(524)
+
+	id, uuidErr := uuid.Parse("c8f0fa1f-da29-438c-a040-393f1126ad39")
+	if uuidErr != nil {
+		log.Fatalf("Failed to prepare uuid: %s", uuidErr)
+	}
+
+	resp, err := client.Replace(spaceNo, []interface{}{id})
+
+	fmt.Println("UUID tuple replace")
+	fmt.Println("Error", err)
+	fmt.Println("Code", resp.Code)
+	fmt.Println("Data", resp.Data)
+
+	// Output:
+	// UUID tuple replace
+	// Error <nil>
+	// Code 0
+	// Data [[c8f0fa1f-da29-438c-a040-393f1126ad39]]
+}