diff --git a/compiler/internal/build/build_test.go b/compiler/internal/build/build_test.go
new file mode 100644
index 00000000..6f3d336b
--- /dev/null
+++ b/compiler/internal/build/build_test.go
@@ -0,0 +1,42 @@
+package build
+
+import (
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/goplus/llgo/compiler/internal/mockable"
+)
+
+func mockRun(args []string, cfg *Config) {
+	mockable.EnableMock()
+	defer func() {
+		if r := recover(); r != nil {
+			if r != "exit" {
+				panic(r)
+			} else {
+				exitCode := mockable.ExitCode()
+				if (exitCode != 0) != false {
+					panic(fmt.Errorf("got exit code %d", exitCode))
+				}
+			}
+		}
+	}()
+	file, _ := os.CreateTemp("", "llgo-*")
+	cfg.OutFile = file.Name()
+	file.Close()
+	defer os.Remove(cfg.OutFile)
+	Do(args, cfg)
+}
+
+func TestRun(t *testing.T) {
+	mockRun([]string{"../../cl/_testgo/print"}, &Config{Mode: ModeRun})
+}
+
+func TestTest(t *testing.T) {
+	mockRun([]string{"../../../_demo/runtest"}, &Config{Mode: ModeTest})
+}
+
+func TestCmpTest(t *testing.T) {
+	mockRun([]string{"../../../_demo/runtest"}, &Config{Mode: ModeCmpTest})
+}