Unit test for SurfaceDensity appearance in ParticleLayoutItem

Tests/UnitTests/GUI/TestGUI.cpp

@@ -45,6 +45,7 @@
 #include "TestSessionItemData.h"
 #include "TestSessionItemTags.h"
 #include "TestMessageService.h"
+#include "TestParticleLayoutItem.h"
 
 int main(int argc, char** argv) {
     QCoreApplication app(argc, argv);

Tests/UnitTests/GUI/TestParticleLayoutItem.h

+#include "InterferenceFunctionItems.h"
+#include "ParticleLayoutItem.h"
+#include "SampleModel.h"
+#include "SessionItemUtils.h"
+#include "google_test.h"
+
+class TestParticleLayoutItem : public ::testing::Test
+{
+public:
+    ~TestParticleLayoutItem();
+};
+
+TestParticleLayoutItem::~TestParticleLayoutItem() = default;
+
+using namespace SessionItemUtils;
+
+//! Checks enabled/disabled status of TotalDensity when adding interference function items.
+
+TEST_F(TestParticleLayoutItem, densityAppearance)
+{
+    SampleModel model;
+    auto layout
+        = dynamic_cast<ParticleLayoutItem*>(model.insertNewItem(Constants::ParticleLayoutType));
+
+    // empty layout should have TotalDensity enabled
+    EXPECT_TRUE(layout->getItem(ParticleLayoutItem::P_TOTAL_DENSITY)->isEnabled());
+
+    // adding radial paracrystal shouldn't change it
+    auto interference
+        = model.insertNewItem(Constants::InterferenceFunctionRadialParaCrystalType,
+                              model.indexOfItem(layout), -1, ParticleLayoutItem::T_INTERFERENCE);
+    EXPECT_TRUE(layout->getItem(ParticleLayoutItem::P_TOTAL_DENSITY)->isEnabled());
+
+    // removing paracrystal, TotalDensity still enabled
+    layout->takeRow(ParentRow(*interference));
+    EXPECT_TRUE(layout->getItem(ParticleLayoutItem::P_TOTAL_DENSITY)->isEnabled());
+    delete interference;
+
+    // adding 2d interference, TotalDensity should be disabled
+    interference
+        = model.insertNewItem(Constants::InterferenceFunction2DLatticeType,
+                              model.indexOfItem(layout), -1, ParticleLayoutItem::T_INTERFERENCE);
+    EXPECT_FALSE(layout->getItem(ParticleLayoutItem::P_TOTAL_DENSITY)->isEnabled());
+
+    // removing 2D interference, TotalIntensity should be reenabled
+    layout->takeRow(ParentRow(*interference));
+    EXPECT_TRUE(layout->getItem(ParticleLayoutItem::P_TOTAL_DENSITY)->isEnabled());
+    delete interference;
+}