Window: Relaxed the internal stack size checker to allow Push/Begin/Pop/.../End patterns to be used with PushStyleColor, PushStyleVar, PushFont without causing a false positive assert. (#1767)

CHANGELOG.txt

@@ -42,7 +42,7 @@ VERSION 1.61 WIP
 Breaking Changes:
 (IN PROGRESS, WILL ADD TO THIS LIST AS WE WORK ON 1.61)
 
- - Misc: IM_DELETE() helper function added in 1.60 doesn't clear the input _pointer_ reference, more consistent with expectation and allows passing r-value.
+ - Misc: IM_DELETE() helper function added in 1.60 doesn't set the input pointer to NULL, more consistent with standard expectation and allows passing r-value.
 
 Other Changes:
 (IN PROGRESS, WILL ADD TO THIS LIST AS WE WORK ON 1.61)
@@ -51,6 +51,7 @@ Other Changes:
 - Window: Fixed default proportional item width lagging by one frame on resize.
 - Window: Fixed popups/tooltips/menus not honoring style.DisplaySafeAreaPadding as well as it should have (part of menus displayed outside the safe area, etc.).
 - Window: Fixed windows using the ImGuiWindowFlags_NoSavedSettings flag from not using the same default position as other windows. (#1760)
+- Window: Relaxed the internal stack size checker to allow Push/Begin/Pop/.../End patterns to be used with PushStyleColor, PushStyleVar, PushFont without causing a false positive assert. (#1767)
 - Columns: Fixed a bug introduced in 1.51 where columns would affect the contents size of their container, often creating feedback loops when ImGuiWindowFlags_AlwaysAutoResize was used. (#1760)
 - MenuBar: Made BeginMainMenuBar() honor style.DisplaySafeAreaPadding so the text can be made visible on TV settings that don't display all pixels. (#1439) [@dougbinks]
 - InputText: On Mac OS X, filter out characters when the Cmd modifier is held. (#1747) [@sivu]

imgui.cpp

@@ -5222,9 +5222,10 @@ static void CheckStacksSize(ImGuiWindow* window, bool write)
     { int current = window->IDStack.Size;       if (write) *p_backup = current; else IM_ASSERT(*p_backup == current && "PushID/PopID or TreeNode/TreePop Mismatch!");   p_backup++; }    // Too few or too many PopID()/TreePop()
     { int current = window->DC.GroupStack.Size; if (write) *p_backup = current; else IM_ASSERT(*p_backup == current && "BeginGroup/EndGroup Mismatch!");                p_backup++; }    // Too few or too many EndGroup()
     { int current = g.CurrentPopupStack.Size;   if (write) *p_backup = current; else IM_ASSERT(*p_backup == current && "BeginMenu/EndMenu or BeginPopup/EndPopup Mismatch"); p_backup++;}// Too few or too many EndMenu()/EndPopup()
-    { int current = g.ColorModifiers.Size;      if (write) *p_backup = current; else IM_ASSERT(*p_backup == current && "PushStyleColor/PopStyleColor Mismatch!");       p_backup++; }    // Too few or too many PopStyleColor()
+    // For color, style and font stacks there is an incentive to use Push/Begin/Pop/.../End patterns, so we relax our checks a little to allow them.
-    { int current = g.StyleModifiers.Size;      if (write) *p_backup = current; else IM_ASSERT(*p_backup == current && "PushStyleVar/PopStyleVar Mismatch!");           p_backup++; }    // Too few or too many PopStyleVar()
+    { int current = g.ColorModifiers.Size;      if (write) *p_backup = current; else IM_ASSERT(*p_backup >= current && "PushStyleColor/PopStyleColor Mismatch!");       p_backup++; }    // Too few or too many PopStyleColor()
-    { int current = g.FontStack.Size;           if (write) *p_backup = current; else IM_ASSERT(*p_backup == current && "PushFont/PopFont Mismatch!");                   p_backup++; }    // Too few or too many PopFont()
+    { int current = g.StyleModifiers.Size;      if (write) *p_backup = current; else IM_ASSERT(*p_backup >= current && "PushStyleVar/PopStyleVar Mismatch!");           p_backup++; }    // Too few or too many PopStyleVar()
+    { int current = g.FontStack.Size;           if (write) *p_backup = current; else IM_ASSERT(*p_backup >= current && "PushFont/PopFont Mismatch!");                   p_backup++; }    // Too few or too many PopFont()
     IM_ASSERT(p_backup == window->DC.StackSizesBackup + IM_ARRAYSIZE(window->DC.StackSizesBackup));
 }