diff --git a/apps/calculation/additional_outputs/illustrated_list_controller.cpp b/apps/calculation/additional_outputs/illustrated_list_controller.cpp
index 432bf49c1..e8b3fbb8d 100644
--- a/apps/calculation/additional_outputs/illustrated_list_controller.cpp
+++ b/apps/calculation/additional_outputs/illustrated_list_controller.cpp
@@ -78,7 +78,7 @@ KDCoordinate IllustratedListController::rowHeight(int j) {
     return 0;
   }
   Shared::ExpiringPointer<Calculation> calculation = m_calculationStore.calculationAtIndex(calculationIndex);
-  return calculation->height(App::app()->localContext(), Metric::CommonSmallMargin, true, true) + Metric::CellSeparatorThickness;
+  return calculation->height(App::app()->localContext(), Metric::CommonSmallMargin, true, true) + Metric::CellSeparatorThickness; //TODO LEA
 }
 
 int IllustratedListController::typeAtLocation(int i, int j) {
diff --git a/apps/calculation/calculation.cpp b/apps/calculation/calculation.cpp
index 22c84be74..0ec02edb3 100644
--- a/apps/calculation/calculation.cpp
+++ b/apps/calculation/calculation.cpp
@@ -124,7 +124,7 @@ Layout Calculation::createApproximateOutputLayout(Context * context, bool * coul
   }
 }
 
-KDCoordinate Calculation::height(Context * context, float verticalMargin, bool expanded, bool forceSingleLine) {
+KDCoordinate Calculation::height(Context * context, float verticalMargin, bool expanded, bool forceSingleLine, CanBeSingleLineFunction canBeSingleLine) {
   KDCoordinate result = expanded ? m_expandedHeight : m_height;
   if (result >= 0) {
     // Height already computed
@@ -157,7 +157,7 @@ KDCoordinate Calculation::height(Context * context, float verticalMargin, bool e
   if (displayOutput(context) == DisplayOutput::ExactOnly) {
     KDCoordinate exactOutputHeight = exactLayout.layoutSize().height();
     KDCoordinate exactOutputWidth = exactLayout.layoutSize().width();
-    bool singleLine = forceSingleLine || ((exactOutputWidth + inputWidth) < maxWidth - 2); //TODO LEA 2
+    bool singleLine = forceSingleLine || canBeSingleLine(inputWidth, exactOutputWidth);
     if (singleLine) {
       KDCoordinate exactOutputBaseline = exactLayout.baseline();
       result = std::max(inputBaseline, exactOutputBaseline) // Above the baseline
@@ -188,7 +188,7 @@ KDCoordinate Calculation::height(Context * context, float verticalMargin, bool e
     KDCoordinate approximateOutputHeight = approximateLayout.layoutSize().height();
     KDCoordinate approximateOutputWidth = approximateLayout.layoutSize().width();
     if (displayOutput(context) == DisplayOutput::ApproximateOnly || (!expanded && displayOutput(context) == DisplayOutput::ExactAndApproximateToggle)) {
-      bool singleLine = forceSingleLine || ((approximateOutputWidth + inputWidth) < maxWidth); // TODO LEA 2
+      bool singleLine = forceSingleLine || canBeSingleLine(inputWidth, approximateOutputWidth);
       if (singleLine) {
         KDCoordinate approximateOutputBaseline = approximateLayout.baseline();
         result = std::max(inputBaseline, approximateOutputBaseline) // Above the baseline
@@ -203,7 +203,7 @@ KDCoordinate Calculation::height(Context * context, float verticalMargin, bool e
       KDCoordinate exactOutputWidth = exactLayout.layoutSize().width();
       KDCoordinate approximateOutputWidth = approximateLayout.layoutSize().width();
       KDCoordinate approximateOutputBaseline = approximateLayout.baseline();
-      bool singleLine = forceSingleLine || ((inputWidth + exactOutputWidth + approximateOutputWidth) < (maxWidth - 30)); // the 30 represents the = sign (example: sin(30)) TODO LEA
+      bool singleLine = forceSingleLine || canBeSingleLine(inputWidth, exactOutputWidth + /*TODO LEA equal sign " = "*/ + approximateOutputWidth);
       if (singleLine) {
         result = std::max(inputBaseline, std::max(exactOutputBaseline, approximateOutputBaseline)) // Above the baseline
           + std::max(inputHeight - inputBaseline, // Beloxw the baseline
diff --git a/apps/calculation/calculation.h b/apps/calculation/calculation.h
index 767fc1e67..ec7dc3895 100644
--- a/apps/calculation/calculation.h
+++ b/apps/calculation/calculation.h
@@ -84,7 +84,8 @@ public:
   Poincare::Layout createApproximateOutputLayout(Poincare::Context * context, bool * couldNotCreateApproximateLayout);
 
   // Memoization of height
-  KDCoordinate height(Poincare::Context * context, float verticalMargin, bool expanded, bool forceSingleLine);
+  typedef bool (*CanBeSingleLineFunction)(KDCoordinate inputWidth, KDCoordinate outputWidth);
+  KDCoordinate height(Poincare::Context * context, float verticalMargin, bool expanded, bool forceSingleLine, CanBeSingleLineFunction canbeSingleLine = [](KDCoordinate inputWidth, KDCoordinate outputWidth) { assert(false); return true; });
 
   // Displayed output
   DisplayOutput displayOutput(Poincare::Context * context);
@@ -95,7 +96,6 @@ public:
   // Additional Information
   AdditionalInformationType additionalInformationType(Poincare::Context * context);
 private:
-  static constexpr int maxWidth = Ion::Display::Width - (Metric::CommonSmallMargin * 2) - Metric::EllipsisCellWidth - 48; // 48 is the difference history_view_cell's width and calculation's
   static constexpr int k_numberOfExpressions = 4;
   static constexpr KDCoordinate k_heightComputationFailureHeight = 50;
   static constexpr const char * k_maximalIntegerWithAdditionalInformation = "10000000000000000";
diff --git a/apps/calculation/history_controller.cpp b/apps/calculation/history_controller.cpp
index 7d763ec22..18669503f 100644
--- a/apps/calculation/history_controller.cpp
+++ b/apps/calculation/history_controller.cpp
@@ -208,7 +208,7 @@ KDCoordinate HistoryController::rowHeight(int j) {
     return 0;
   }
   Shared::ExpiringPointer<Calculation> calculation = calculationAtIndex(j);
-  return calculation->height(App::app()->localContext(), HistoryViewCell::k_verticalMargin, j == selectedRow() && selectedSubviewType() == SubviewType::Output, false);
+  return calculation->height(App::app()->localContext(), HistoryViewCell::k_verticalMargin, j == selectedRow() && selectedSubviewType() == SubviewType::Output, false, &HistoryViewCell::CanBeSingleLine);
 }
 
 int HistoryController::typeAtLocation(int i, int j) {
diff --git a/apps/calculation/history_view_cell.cpp b/apps/calculation/history_view_cell.cpp
index 43251acc8..8ea49b677 100644
--- a/apps/calculation/history_view_cell.cpp
+++ b/apps/calculation/history_view_cell.cpp
@@ -169,6 +169,11 @@ View * HistoryViewCell::subviewAtIndex(int index) {
   return views[index];
 }
 
+bool HistoryViewCell::CanBeSingleLine(KDCoordinate inputWidth, KDCoordinate outputWidth) {
+  // k_margin is the separation between the input and output.
+  return (inputWidth + k_margin + outputWidth) < (Ion::Display::Width - Metric::EllipsisCellWidth - 2 * k_margin);
+}
+
 void HistoryViewCell::layoutSubviews(bool force) {
   KDCoordinate maxFrameWidth = bounds().width();
   if (displayedEllipsis()) {
@@ -179,7 +184,8 @@ void HistoryViewCell::layoutSubviews(bool force) {
   }
   KDSize inputSize = m_inputView.minimalSizeForOptimalDisplay();
   KDSize outputSize = m_scrollableOutputView.minimalSizeForOptimalDisplay();
-  bool singleLine = (inputSize.width() + k_margin + outputSize.width()) < bounds().width() - Metric::EllipsisCellWidth; // k_margin the separation between the input and output. inputSize and outputSize already handle their left and right margins TODO LEA factorize singleLine()
+
+  bool singleLine = CanBeSingleLine(inputSize.width(), outputSize.width());
 
   KDCoordinate inputY = k_margin;
   KDCoordinate outputY = k_margin;
diff --git a/apps/calculation/history_view_cell.h b/apps/calculation/history_view_cell.h
index 0df307b5e..a47b43a4d 100644
--- a/apps/calculation/history_view_cell.h
+++ b/apps/calculation/history_view_cell.h
@@ -33,6 +33,7 @@ class HistoryViewCell : public ::EvenOddCell, public Responder {
 public:
   constexpr static KDCoordinate k_verticalMargin = Metric::CommonLargeMargin; //TODO LEA same as k_horizontalMargin?
   HistoryViewCell(Responder * parentResponder = nullptr);
+  static bool CanBeSingleLine(KDCoordinate inputWidth, KDCoordinate outputWidth);
   void cellDidSelectSubview(HistoryViewCellDataSource::SubviewType type, HistoryViewCellDataSource::SubviewType previousType = HistoryViewCellDataSource::SubviewType::None);
   void setEven(bool even) override;
   void setHighlighted(bool highlight) override;