add error pkg

internal/errors/caos_error_test.go

@@ -0,0 +1,19 @@
+package errors_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	caos_errs "github.com/caos/utils/errors"
+)
+
+func TestErrorMethod(t *testing.T) {
+	err := caos_errs.ThrowError(nil, "id", "msg")
+	expected := "ID=id Message=msg"
+	assert.Equal(t, expected, err.Error())
+
+	err = caos_errs.ThrowError(err, "subID", "subMsg")
+	subExptected := "ID=subID Message=subMsg Parent=(ID=id Message=msg)"
+	assert.Equal(t, subExptected, err.Error())
+}