Tests: Changed prototype of ImGuiTestEngineHook_ItemAdd to match functions called in same spot. Made ButtonBehavior submit fallback item info if ItemAdd() was not called (for resize grips, resize borders, scrollbar, columns, etc.)

imgui.cpp

@@ -2630,7 +2630,7 @@ bool ImGui::ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb_arg)
     window->DC.LastItemStatusFlags = ImGuiItemStatusFlags_None;
 
 #ifdef IMGUI_ENABLE_TEST_ENGINE
-    ImGuiTestEngineHook_ItemAdd(id, bb);
+    ImGuiTestEngineHook_ItemAdd(bb, id);
 #endif
 
     // Clipping test

imgui_internal.h

@@ -1427,7 +1427,7 @@ IMGUI_API void              ImFontAtlasBuildMultiplyRectAlpha8(const unsigned ch
 #ifdef IMGUI_ENABLE_TEST_ENGINE
 extern void                 ImGuiTestEngineHook_PreNewFrame();
 extern void                 ImGuiTestEngineHook_PostNewFrame();
-extern void                 ImGuiTestEngineHook_ItemAdd(ImGuiID id, const ImRect& bb);
+extern void                 ImGuiTestEngineHook_ItemAdd(const ImRect& bb, ImGuiID id);
 extern void                 ImGuiTestEngineHook_ItemInfo(ImGuiID id, const char* label, int flags);
 #define IMGUI_TEST_ENGINE_ITEM_INFO(_ID, _LABEL, _FLAGS)  ImGuiTestEngineHook_ItemInfo(_ID, _LABEL, _FLAGS)   // Register status flags
 #else

imgui_widgets.cpp

@@ -396,6 +396,11 @@ bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool
     if ((flags & ImGuiButtonFlags_FlattenChildren) && g.HoveredRootWindow == window)
         g.HoveredWindow = window;
 
+#ifdef IMGUI_ENABLE_TEST_ENGINE
+    if (window->DC.LastItemId != id)
+        ImGuiTestEngineHook_ItemAdd(bb, id);
+#endif
+
     bool pressed = false;
     bool hovered = ItemHoverable(bb, id);