chore: move common packages to internal

internal/util/util_test.go

@@ -0,0 +1,31 @@
+package util
+
+import (
+	"testing"
+)
+
+func TestValidateEmail(t *testing.T) {
+	tests := []struct {
+		email string
+		want  bool
+	}{
+		{
+			email: "t@gmail.com",
+			want:  true,
+		},
+		{
+			email: "@qq.com",
+			want:  false,
+		},
+		{
+			email: "1@gmail",
+			want:  true,
+		},
+	}
+	for _, test := range tests {
+		result := ValidateEmail(test.email)
+		if result != test.want {
+			t.Errorf("Validate Email %s: got result %v, want %v.", test.email, result, test.want)
+		}
+	}
+}