learn_mqtt_go/common/common_test.go

package common

import (
	"os"
	"testing"
)

var testEnvKey string = "TEST_MQTT_KEY"

func assertError(t testing.TB, got, want string) {
	t.Helper()
	if got != want {
		t.Errorf("Error: got '%s', want '%s'", got, want)
	}
}

func TestGetenvDefault(t *testing.T) {
	t.Run("key not set", func(t *testing.T) {
		originalEnv := os.Getenv(testEnvKey)
		os.Unsetenv(testEnvKey)
		defer os.Setenv(testEnvKey, originalEnv)

		got := GetenvDefault(testEnvKey, "found")
		want := "found"

		assertError(t, got, want)
	})

	t.Run("key set", func(t *testing.T) {
		originalEnv := os.Getenv(testEnvKey)
		os.Setenv(testEnvKey, "batman")
		defer os.Setenv(testEnvKey, originalEnv)

		got := GetenvDefault(testEnvKey, "found")
		want := "batman"
		assertError(t, got, want)

	})
}