Restructure project directories

Follow the standard of all go projects

internal/echo/echo.go

@@ -0,0 +1,72 @@
+package echo
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+const (
+	ColorReset  = "\033[0m"
+	ColorRed    = "\033[31m"
+	ColorGreen  = "\033[32m"
+	ColorYellow = "\033[33m"
+	ColorBlue   = "\033[34m"
+)
+
+var (
+	useColor bool      = false
+	output   io.Writer = os.Stdout
+)
+
+func Color(enabled bool) {
+	useColor = enabled
+}
+
+func Output(writer io.Writer) {
+	output = writer
+}
+
+func ErrorfMsg(format string, a ...interface{}) error {
+	msg := fmt.Sprintf(format, a...)
+	if useColor {
+		msg = fmt.Sprintf("%vError:%v %v", ColorRed, ColorReset, msg)
+	} else {
+		msg = fmt.Sprintf("Error: %v", msg)
+	}
+	return write(msg)
+}
+
+func InfoFMsg(format string, a ...interface{}) error {
+	msg := fmt.Sprintf(format, a...)
+	if useColor {
+		msg = fmt.Sprintf("%vInfo:%v %v", ColorBlue, ColorReset, msg)
+	} else {
+		msg = fmt.Sprintf("Info: %v", msg)
+	}
+	return write(msg)
+}
+
+func GreenMessageF(format string, a ...interface{}) error {
+	return writeWithColor(fmt.Sprintf(format, a...), ColorGreen)
+}
+
+func YellowMessageF(format string, a ...interface{}) error {
+	return writeWithColor(fmt.Sprintf(format, a...), ColorYellow)
+}
+func RedMessageF(format string, a ...interface{}) error {
+	return writeWithColor(fmt.Sprintf(format, a...), ColorRed)
+}
+
+func writeWithColor(msg string, color string) error {
+	if useColor {
+		return write(fmt.Sprintf("%v%v%v", color, msg, ColorReset))
+	}
+	return write(msg)
+
+}
+
+func write(msg string) error {
+	_, err := fmt.Fprintln(output, msg)
+	return err
+}

internal/echo/echo_test.go

@@ -0,0 +1,151 @@
+package echo
+
+import (
+	"fmt"
+	"os"
+	"testing"
+)
+
+type ExpectedMessageTester struct {
+	expectedMessage string
+}
+
+func (emt ExpectedMessageTester) Write(p []byte) (n int, err error) {
+	msg := string(p)
+	if msg != emt.expectedMessage {
+		return 0, fmt.Errorf("expected to get \"%v\", instead of this got \"%v\"", msg, emt.expectedMessage)
+	}
+
+	return 0, nil
+}
+
+func TestOverwriteColor(t *testing.T) {
+	Color(false)
+	if useColor {
+		t.Error("Expected that \"useColor\" will be false")
+	}
+	Color(true)
+	if !useColor {
+		t.Error("Expected that \"useColor\" will be true")
+	}
+}
+
+func TestOverwriteWriter(t *testing.T) {
+	Output(os.Stderr)
+	if output != os.Stderr {
+		t.Error("Expected to receive addresses on os.Stderr")
+	}
+	Output(os.Stdout)
+	if output != os.Stdout {
+		t.Error("Expected to receive addresses on os.Stdout")
+	}
+}
+
+func TestErrorfMsgWithoutColor(t *testing.T) {
+	useColor = false
+	output = ExpectedMessageTester{
+		expectedMessage: "Error: test message\n",
+	}
+	err := ErrorfMsg("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestErrorfMsgWithColor(t *testing.T) {
+	useColor = true
+	output = ExpectedMessageTester{
+		expectedMessage: "\033[31mError:\033[0m test message\n",
+	}
+	err := ErrorfMsg("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestInfoMsgFWithoutColor(t *testing.T) {
+	useColor = false
+	output = ExpectedMessageTester{
+		expectedMessage: "Info: test message\n",
+	}
+	err := InfoFMsg("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestInfoMsgFWithColor(t *testing.T) {
+	useColor = true
+	output = ExpectedMessageTester{
+		expectedMessage: "\033[34mInfo:\033[0m test message\n",
+	}
+	err := InfoFMsg("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestGreenMessageWithoutColor(t *testing.T) {
+	useColor = false
+	output = ExpectedMessageTester{
+		expectedMessage: "test message\n",
+	}
+	err := GreenMessageF("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestGreenMessageWithColor(t *testing.T) {
+	useColor = true
+	output = ExpectedMessageTester{
+		expectedMessage: "\033[32mtest message\033[0m\n",
+	}
+	err := GreenMessageF("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestYellowMessageWithout(t *testing.T) {
+	useColor = false
+	output = ExpectedMessageTester{
+		expectedMessage: "test message\n",
+	}
+	err := YellowMessageF("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestYellowMessageWithColor(t *testing.T) {
+	useColor = true
+	output = ExpectedMessageTester{
+		expectedMessage: "\033[33mtest message\033[0m\n",
+	}
+	err := YellowMessageF("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+
+func TestRedMessageWithout(t *testing.T) {
+	useColor = false
+	output = ExpectedMessageTester{
+		expectedMessage: "test message\n",
+	}
+	err := RedMessageF("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}
+func TestRedMessageWithColor(t *testing.T) {
+	useColor = true
+	output = ExpectedMessageTester{
+		expectedMessage: "\033[31mtest message\033[0m\n",
+	}
+	err := RedMessageF("test message")
+	if err != nil {
+		t.Error(err)
+	}
+}