Added io.ConfigDebugHighlightIdConflicts debug feature! (#7961, #7669)

Also #74, #96, #480, #501, #647, #654, #719, #843, #894, #1057, #1173, #1390, #1414, #1556, #1768, #2041, #2116, #2330, #2475, #2562, #2667, #2807, #2885, #3102, #3375, #3526, #3964, #4008, #4070, #4158, #4172, #4199, #4375, #4395, #4471, #4548, #4612, #4631, #4657, #4796, #5210, #5303, #5360, #5393, #5533, #5692, #5707, #5729, #5773, #5787, #5884, #6046, #6093, #6186, #6223, #6364, #6387, #6567, #6692, #6724, #6939, #6984, #7246, #7270, #7375, #7421, #7434, #7472, #7581, #7724, #7926, #7937 and probably more.. Tagging to increase visibility!

imgui.h

@@ -29,7 +29,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM >= 12345')
 #define IMGUI_VERSION       "1.91.2 WIP"
-#define IMGUI_VERSION_NUM   19112
+#define IMGUI_VERSION_NUM   19113
 #define IMGUI_HAS_TABLE
 
 /*
@@ -1135,6 +1135,7 @@ enum ImGuiItemFlags_
     ImGuiItemFlags_NoNavDefaultFocus        = 1 << 2,   // false    // Disable item being a candidate for default focus (e.g. used by title bar items).
     ImGuiItemFlags_ButtonRepeat             = 1 << 3,   // false    // Any button-like behavior will have repeat mode enabled (based on io.KeyRepeatDelay and io.KeyRepeatRate values). Note that you can also call IsItemActive() after any button to tell if it is being held.
     ImGuiItemFlags_AutoClosePopups          = 1 << 4,   // true     // MenuItem()/Selectable() automatically close their parent popup window.
+    ImGuiItemFlags_AllowDuplicateId         = 1 << 5,   // false    // Allow submitting an item with the same identifier as an item already submitted this frame without triggering a warning tooltip if io.ConfigDebugHighlightIdConflicts is set.
 };
 
 // Flags for ImGui::InputText()
@@ -2231,6 +2232,7 @@ struct ImGuiIO
     const char* LogFilename;                    // = "imgui_log.txt"// Path to .log file (default parameter to ImGui::LogToFile when no file is specified).
     void*       UserData;                       // = NULL           // Store your own data.
 
+    // Font system
     ImFontAtlas*Fonts;                          // <auto>           // Font atlas: load, rasterize and pack one or more fonts into a single texture.
     float       FontGlobalScale;                // = 1.0f           // Global scale all fonts
     bool        FontAllowUserScaling;           // = false          // Allow user scaling text of individual window with CTRL+Wheel.
@@ -2238,6 +2240,7 @@ struct ImGuiIO
     ImVec2      DisplayFramebufferScale;        // = (1, 1)         // For retina display or other situations where window coordinates are different from framebuffer coordinates. This generally ends up in ImDrawData::FramebufferScale.
 
     // Miscellaneous options
+    // (you can visualize and interact with all options in 'Demo->Configuration')
     bool        MouseDrawCursor;                // = false          // Request ImGui to draw a mouse cursor for you (if you are on a platform without a mouse cursor). Cannot be easily renamed to 'io.ConfigXXX' because this is frequently used by backend implementations.
     bool        ConfigMacOSXBehaviors;          // = defined(__APPLE__) // Swap Cmd<>Ctrl keys + OS X style text editing cursor movement using Alt instead of Ctrl, Shortcuts using Cmd/Super instead of Ctrl, Line/Text Start and End using Cmd+Arrows instead of Home/End, Double click selects by word instead of selecting whole text, Multi-selection in lists uses Cmd/Super instead of Ctrl.
     bool        ConfigNavSwapGamepadButtons;    // = false          // Swap Activate<>Cancel (A<>B) buttons, matching typical "Nintendo/Japanese style" gamepad layout.
@@ -2267,6 +2270,12 @@ struct ImGuiIO
     //   e.g. io.ConfigDebugIsDebuggerPresent = ::IsDebuggerPresent() on Win32, or refer to ImOsIsDebuggerPresent() imgui_test_engine/imgui_te_utils.cpp for a Unix compatible version).
     bool        ConfigDebugIsDebuggerPresent;   // = false          // Enable various tools calling IM_DEBUG_BREAK().
 
+    // Tools to detect code submitting items with conflicting/duplicate IDs
+    // - Code should use PushID()/PopID() in loops, or append "##xx" to same-label identifiers.
+    // - Empty label e.g. Button("") == same ID as parent widget/node. Use Button("##xx") instead!
+    // - See FAQ https://github.com/ocornut/imgui/blob/master/docs/FAQ.md#q-about-the-id-stack-system
+    bool        ConfigDebugHighlightIdConflicts;// = true           // Highlight and show an error message when multiple items have conflicting identifiers.
+
     // Tools to test correct Begin/End and BeginChild/EndChild behaviors.
     // - Presently Begin()/End() and BeginChild()/EndChild() needs to ALWAYS be called in tandem, regardless of return value of BeginXXX()
     // - This is inconsistent with other BeginXXX functions and create confusion for many users.