Add initial c++ testing infrastructure

wpilibc/src/test/native/cpp/AlertsTest.cpp

@@ -4,27 +4,90 @@
 
 #include <frc/Alert.h>
 
+#include <algorithm>
 #include <chrono>
+#include <map>
 #include <string>
 #include <utility>
 
 #include <fmt/format.h>
 #include <gtest/gtest.h>
+#include <networktables/NetworkTableInstance.h>
+#include <networktables/StringArrayTopic.h>
 
-TEST(AlertsTest, Smoke) {
+using namespace frc;
+using enum Alert::AlertType;
+class AlertsTest : public ::testing::Test {
+ public:
+  ~AlertsTest() {
+    EXPECT_EQ(GetSubscriberForType(kError).Get().size(), 0);
+    EXPECT_EQ(GetSubscriberForType(kWarning).Get().size(), 0);
+    EXPECT_EQ(GetSubscriberForType(kInfo).Get().size(), 0);
+  }
+
+  template <typename... Args>
+  Alert MakeAlert(Args&&... args) {
+    return Alert(GetGroupName(), std::forward<Args>(args)...);
+  }
+
+  std::string GetGroupName() {
+    const ::testing::TestInfo* testInfo =
+        ::testing::UnitTest::GetInstance()->current_test_info();
+    return fmt::format("{}_{}", testInfo->test_suite_name(),
+                       testInfo->test_case_name());
+  }
+
+  bool IsAlertActive(std::string_view text, Alert::AlertType type) {
+    std::vector<std::string> activeAlerts = GetSubscriberForType(type).Get();
+    return std::find(activeAlerts.begin(), activeAlerts.end(), text) !=
+           activeAlerts.end();
+  }
+
+ private:
+  std::string GetSubtableName(Alert::AlertType type) {
+    switch (type) {
+      case kError:
+        return "errors";
+      case kWarning:
+        return "warnings";
+      case kInfo:
+        return "infos";
+      default:
+        return "unknown";
+    }
+  }
+
+  std::map<Alert::AlertType, nt::StringArraySubscriber> m_subs;
+  const nt::StringArraySubscriber& GetSubscriberForType(Alert::AlertType type) {
+    if (m_subs.contains(type)) {
+      return m_subs[type];
+    } else {
+      return m_subs
+          .emplace(std::make_pair(
+              type, nt::NetworkTableInstance::GetDefault()
+                        .GetStringArrayTopic(
+                            fmt::format("/SmartDashboard/{}/{}", GetGroupName(),
+                                        GetSubtableName(type)))
+                        .Subscribe({})))
+          .first->second;
+    }
+  }
+};
+
+TEST_F(AlertsTest, Constructors) {
   // Make and destroy
-  frc::Alert("One", frc::Alert::AlertType::kError);
-  frc::Alert a{"Two", frc::Alert::AlertType::kInfo};
+  Alert{GetGroupName(), "One", kError};
+  Alert a{GetGroupName(), "Two", kInfo};
   a.Set(true);
   a.Set(false);
   // Move assign
-  a = frc::Alert("Three", frc::Alert::AlertType::kWarning);
+  a = Alert(GetGroupName(), "Three", kWarning);
   // Move construct
-  frc::Alert b{std::move(a)};
+  Alert b{std::move(a)};
   {
     // Move assign with dynamic string
     std::string text = fmt::format(
         "{}", std::chrono::steady_clock::now().time_since_epoch().count());
-    b = frc::Alert(text, frc::Alert::AlertType::kError);
+    b = Alert(text, kError);
   }
 }