Tests: Add unit tests

internal/api/api_response_test.go

@@ -0,0 +1,16 @@
+package api
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewResponse(t *testing.T) {
+	t.Run("404", func(t *testing.T) {
+		r := NewResponse(404, errors.New("not found"), "details")
+		assert.Equal(t, 404, r.Code)
+		assert.Equal(t, "details", r.Details)
+	})
+}