[expression_editor/poincare] Move Down in an ExpressionLayout.

Change-Id: I87f3394cce5eb4936ab926d5e92fdf44d4473cf7

poincare/include/poincare/expression_layout.h

@@ -32,6 +32,8 @@ public:
   virtual bool moveRight(ExpressionLayoutCursor * cursor) { return false; } //TODO should be virtual pure?
   virtual bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout = nullptr, ExpressionLayout * previousPreviousLayout = nullptr);
   bool moveUpInside(ExpressionLayoutCursor * cursor);
+  virtual bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout = nullptr, ExpressionLayout * previousPreviousLayout = nullptr);
+  bool moveDownInside(ExpressionLayoutCursor * cursor);
 protected:
   virtual void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) = 0;
   virtual KDSize computeSize() = 0;

poincare/src/expression_layout_cursor.cpp

@@ -17,7 +17,7 @@ bool ExpressionLayoutCursor::moveUp() {
 }
 
 bool ExpressionLayoutCursor::moveDown() {
-  return false; //TODO
+  return m_pointedExpressionLayout->moveDown(this);
 }
 
 bool ExpressionLayoutCursor::positionIsEquivalentTo(ExpressionLayout * expressionLayout, Position position, int positionIndex) {

poincare/src/layout/condensed_sum_layout.cpp

@@ -125,6 +125,23 @@ bool CondensedSumLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayou
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
 
+bool CondensedSumLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // If the cursor is inside the superscript layout, move it to the subscript.
+  if (m_superscriptLayout && previousLayout == m_superscriptLayout) {
+    assert(m_subscriptLayout != nullptr);
+    return m_subscriptLayout->moveUpInside(cursor);
+  }
+  // If the cursor is Left of the base layout, move it to the subscript.
+  if (m_baseLayout
+      && previousLayout == m_baseLayout
+      && cursor->positionIsEquivalentTo(m_baseLayout, ExpressionLayoutCursor::Position::Left))
+  {
+    assert(m_subscriptLayout != nullptr);
+    return m_subscriptLayout->moveUpInside(cursor);
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 void CondensedSumLayout::render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) {
   // Nothing to draw
 }

poincare/src/layout/condensed_sum_layout.h

@@ -17,6 +17,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) override;
   KDSize computeSize() override;

poincare/src/layout/editable_baseline_relative_layout.cpp

@@ -132,5 +132,53 @@ bool EditableBaselineRelativeLayout::moveUp(ExpressionLayoutCursor * cursor, Exp
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
 
+bool EditableBaselineRelativeLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // If the baseline is a subscript:
+  if (m_type == BaselineRelativeLayout::Type::Subscript) {
+    // If the cursor is Right of the base layout, move it to the indice.
+    if (m_baseLayout
+        && previousLayout == m_baseLayout
+        && cursor->positionIsEquivalentTo(m_baseLayout, ExpressionLayoutCursor::Position::Right))
+    {
+      assert(m_indiceLayout != nullptr);
+      cursor->setPointedExpressionLayout(m_indiceLayout);
+      cursor->setPosition(ExpressionLayoutCursor::Position::Left);
+      cursor->setPositionInside(0);
+      return true;
+    }
+    // If the cursor is Right, move it to the indice.
+    if (cursor->positionIsEquivalentTo(this, ExpressionLayoutCursor::Position::Right)) {
+      assert(m_indiceLayout != nullptr);
+      cursor->setPointedExpressionLayout(m_indiceLayout);
+      cursor->setPosition(ExpressionLayoutCursor::Position::Right);
+      cursor->setPositionInside(0);
+      return true;
+    }
+  }
+  // If the baseline is a superscript:
+  if (m_type == BaselineRelativeLayout::Type::Superscript
+    && m_indiceLayout
+    && previousLayout == m_indiceLayout)
+  {
+    // If the cursor is Left of the indice layout, move it to the base.
+    if (cursor->positionIsEquivalentTo(m_indiceLayout, ExpressionLayoutCursor::Position::Left)) {
+      assert(m_indiceLayout != nullptr);
+      cursor->setPointedExpressionLayout(m_baseLayout);
+      cursor->setPosition(ExpressionLayoutCursor::Position::Right);
+      cursor->setPositionInside(0);
+      return true;
+    }
+    // If the cursor is Right of the indice layout, move it Right.
+    if (cursor->positionIsEquivalentTo(m_indiceLayout, ExpressionLayoutCursor::Position::Right)) {
+      assert(m_indiceLayout != nullptr);
+      cursor->setPointedExpressionLayout(this);
+      cursor->setPosition(ExpressionLayoutCursor::Position::Right);
+      cursor->setPositionInside(0);
+      return true;
+    }
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 }
 

poincare/src/layout/editable_baseline_relative_layout.h

@@ -11,6 +11,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 };
 
 }

poincare/src/layout/expression_layout.cpp

@@ -70,6 +70,17 @@ bool ExpressionLayout::moveUpInside(ExpressionLayoutCursor * cursor) {
   return moveInside(VerticalDirection::Up, cursor);
 }
 
+bool ExpressionLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  if (m_parent) {
+    return m_parent->moveDown(cursor, this, previousLayout);
+  }
+  return false;
+}
+
+bool ExpressionLayout::moveDownInside(ExpressionLayoutCursor * cursor) {
+  return moveInside(VerticalDirection::Down, cursor);
+}
+
 bool ExpressionLayout::moveInside(VerticalDirection direction, ExpressionLayoutCursor * cursor) {
   ExpressionLayout *  chilResult = nullptr;
   ExpressionLayout ** childResultPtr = &chilResult;

poincare/src/layout/fraction_layout.cpp

@@ -86,6 +86,20 @@ bool FractionLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout *
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
 
+bool FractionLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // If the cursor is inside numerator, move it to the denominator.
+  if (m_numerator_layout && previousLayout == m_numerator_layout) {
+    assert(m_denominator_layout != nullptr);
+    return m_denominator_layout->moveDownInside(cursor);
+  }
+  // If the cursor is Left or Right, move it to the denominator.
+  if (cursor->pointedExpressionLayout() == this){
+    assert(m_denominator_layout != nullptr);
+    return m_denominator_layout->moveDownInside(cursor);
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 void FractionLayout::render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) {
   KDCoordinate fractionLineY = p.y() + m_numerator_layout->size().height() + k_fractionLineMargin;
   ctx->fillRect(KDRect(p.x()+k_fractionBorderMargin, fractionLineY, size().width()-2*k_fractionBorderMargin, 1), expressionColor);

poincare/src/layout/fraction_layout.h

@@ -17,6 +17,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) override;
   KDSize computeSize() override;

poincare/src/layout/grid_layout.cpp

@@ -110,6 +110,16 @@ bool GridLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * prev
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
 
+bool GridLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // If the cursor is child that is not on the bottom row, move it inside the
+  // lower neighbourg.
+  int childIndex = indexOfChild(previousLayout);
+  if (childIndex >- 1 && !childIsBottomOfGrid(childIndex)) {
+    return m_entryLayouts[childIndex + m_numberOfColumns]->moveDownInside(cursor);
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 KDCoordinate GridLayout::rowBaseline(int i) {
   KDCoordinate rowBaseline = 0;
   for (int j = 0; j < m_numberOfColumns; j++) {
@@ -217,4 +227,9 @@ bool GridLayout::childIsTopOfGrid(int index) const {
   return index < m_numberOfColumns;
 }
 
+bool GridLayout::childIsBottomOfGrid(int index) const {
+  assert(index >= 0 && index < m_numberOfRows*m_numberOfColumns);
+  return index > (m_numberOfRows - 1) * m_numberOfColumns - 1;
+}
+
 }

poincare/src/layout/grid_layout.h

@@ -18,6 +18,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) override;
   KDSize computeSize() override;
@@ -34,6 +35,7 @@ private:
   bool childIsLeftOfGrid(int index) const;
   bool childIsRightOfGrid(int index) const;
   bool childIsTopOfGrid(int index) const;
+  bool childIsBottomOfGrid(int index) const;
   ExpressionLayout ** m_entryLayouts;
   int m_numberOfRows;
   int m_numberOfColumns;

poincare/src/layout/horizontal_layout.cpp

@@ -125,36 +125,11 @@ bool HorizontalLayout::moveRight(ExpressionLayoutCursor * cursor) {
 }
 
 bool HorizontalLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
-  // Prevent looping fom child to parent
-  if (previousPreviousLayout == this) {
-    return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
-  }
-  // If the cursor Left or Right of a child, try moving it up from its brother.
-  int previousLayoutIndex = indexOfChild(previousLayout);
-  if (previousLayoutIndex > -1) {
-    ExpressionLayout * brother = nullptr;
-    ExpressionLayoutCursor::Position newPosition = ExpressionLayoutCursor::Position::Right;
-    if (cursor->position() == ExpressionLayoutCursor::Position::Left && previousLayoutIndex > 0) {
-      brother = m_children_layouts[previousLayoutIndex - 1];
-      newPosition = ExpressionLayoutCursor::Position::Right;
-    }
-    if (cursor->position() == ExpressionLayoutCursor::Position::Right && previousLayoutIndex < m_number_of_children - 1) {
-      brother = m_children_layouts[previousLayoutIndex + 1];
-      newPosition = ExpressionLayoutCursor::Position::Left;
-    }
-    if (brother && cursor->positionIsEquivalentTo(brother, newPosition)) {
-      ExpressionLayout * previousPointedLayout = cursor->pointedExpressionLayout();
-      ExpressionLayoutCursor::Position previousPosition = cursor->position();
-      cursor->setPointedExpressionLayout(brother);
-      cursor->setPosition(newPosition);
-      if (brother->moveUp(cursor, this, previousLayout)) {
-        return true;
-      }
-      cursor->setPointedExpressionLayout(previousPointedLayout);
-      cursor->setPosition(previousPosition);
-    }
-  }
-  return ExpressionLayout::moveUp(cursor, previousLayout);
+  return moveVertically(ExpressionLayout::VerticalDirection::Up, cursor, previousLayout, previousPreviousLayout);
+}
+
+bool HorizontalLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  return moveVertically(ExpressionLayout::VerticalDirection::Down, cursor, previousLayout, previousPreviousLayout);
 }
 
 void HorizontalLayout::render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) {
@@ -200,6 +175,50 @@ KDPoint HorizontalLayout::positionOfChild(ExpressionLayout * child) {
   return KDPoint(x, y);
 }
 
+bool HorizontalLayout::moveVertically(ExpressionLayout::VerticalDirection direction, ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // Prevent looping fom child to parent
+  if (previousPreviousLayout == this) {
+    if (direction == ExpressionLayout::VerticalDirection::Up) {
+      return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
+    }
+    assert(direction == ExpressionLayout::VerticalDirection::Down);
+    return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+  }
+  // If the cursor Left or Right of a child, try moving it up from its brother.
+  int previousLayoutIndex = indexOfChild(previousLayout);
+  if (previousLayoutIndex > -1) {
+    ExpressionLayout * brother = nullptr;
+    ExpressionLayoutCursor::Position newPosition = ExpressionLayoutCursor::Position::Right;
+    if (cursor->position() == ExpressionLayoutCursor::Position::Left && previousLayoutIndex > 0) {
+      brother = m_children_layouts[previousLayoutIndex - 1];
+      newPosition = ExpressionLayoutCursor::Position::Right;
+    }
+    if (cursor->position() == ExpressionLayoutCursor::Position::Right && previousLayoutIndex < m_number_of_children - 1) {
+      brother = m_children_layouts[previousLayoutIndex + 1];
+      newPosition = ExpressionLayoutCursor::Position::Left;
+    }
+    if (brother && cursor->positionIsEquivalentTo(brother, newPosition)) {
+      ExpressionLayout * previousPointedLayout = cursor->pointedExpressionLayout();
+      ExpressionLayoutCursor::Position previousPosition = cursor->position();
+      cursor->setPointedExpressionLayout(brother);
+      cursor->setPosition(newPosition);
+      if (direction == ExpressionLayout::VerticalDirection::Up && brother->moveUp(cursor, this, previousLayout)) {
+        return true;
+      }
+      if (direction == ExpressionLayout::VerticalDirection::Down && brother->moveDown(cursor, this, previousLayout)) {
+        return true;
+      }
+      cursor->setPointedExpressionLayout(previousPointedLayout);
+      cursor->setPosition(previousPosition);
+    }
+  }
+  if (direction == ExpressionLayout::VerticalDirection::Up) {
+    return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
+  }
+  assert(direction == ExpressionLayout::VerticalDirection::Down);
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 int HorizontalLayout::indexOfChild(ExpressionLayout * eL) const {
   if (eL == nullptr) {
     return -1;

poincare/src/layout/horizontal_layout.h

@@ -17,12 +17,14 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) override;
   KDSize computeSize() override;
   ExpressionLayout * child(uint16_t index) override;
   KDPoint positionOfChild(ExpressionLayout * child) override;
 private:
+  bool moveVertically(ExpressionLayout::VerticalDirection direction, ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout);
   int indexOfChild(ExpressionLayout * eL) const;
   int m_number_of_children;
   ExpressionLayout ** m_children_layouts;

poincare/src/layout/integral_layout.cpp

@@ -134,6 +134,23 @@ bool IntegralLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout *
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
 
+bool IntegralLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // If the cursor is inside the upper bound, move it to the lower bound.
+  if (m_upperBoundLayout && previousLayout == m_upperBoundLayout) {
+    assert(m_lowerBoundLayout != nullptr);
+    return m_lowerBoundLayout->moveDownInside(cursor);
+  }
+  // If the cursor is Left of the integrand, move it to the lower bound.
+  if (m_integrandLayout
+      && previousLayout == m_integrandLayout
+      && cursor->positionIsEquivalentTo(m_integrandLayout, ExpressionLayoutCursor::Position::Left))
+  {
+    assert(m_lowerBoundLayout != nullptr);
+    return m_lowerBoundLayout->moveDownInside(cursor);
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 void IntegralLayout::render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) {
   KDSize integrandSize = m_integrandLayout->size();
   KDSize upperBoundSize = m_upperBoundLayout->size();

poincare/src/layout/integral_layout.h

@@ -19,6 +19,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) override;
   KDSize computeSize() override;

poincare/src/layout/nth_root_layout.cpp

@@ -146,6 +146,27 @@ bool NthRootLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * p
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
 
+bool NthRootLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  if (m_indexLayout && previousLayout == m_indexLayout) {
+    // If the cursor is Right of the index, move it to the radicand.
+    if (cursor->positionIsEquivalentTo(m_indexLayout, ExpressionLayoutCursor::Position::Right)) {
+      assert(m_radicandLayout != nullptr);
+      cursor->setPointedExpressionLayout(m_radicandLayout);
+      cursor->setPosition(ExpressionLayoutCursor::Position::Left);
+      cursor->setPositionInside(0);
+      return true;
+    }
+    // If the cursor is Left of the index, move it Left .
+    if (cursor->positionIsEquivalentTo(m_indexLayout, ExpressionLayoutCursor::Position::Left)) {
+      cursor->setPointedExpressionLayout(this);
+      cursor->setPosition(ExpressionLayoutCursor::Position::Left);
+      cursor->setPositionInside(0);
+      return true;
+    }
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
+
 void NthRootLayout::render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) {
   KDSize radicandSize = m_radicandLayout->size();
   KDSize indexSize = m_indexLayout != nullptr ? m_indexLayout->size() : KDSize(k_leftRadixWidth,0);

poincare/src/layout/nth_root_layout.h

@@ -19,6 +19,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   void render(KDContext * ctx, KDPoint p, KDColor expressionColor, KDColor backgroundColor) override;
   KDSize computeSize() override;

poincare/src/layout/sequence_layout.cpp

@@ -123,6 +123,22 @@ bool SequenceLayout::moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout *
   }
   return ExpressionLayout::moveUp(cursor, previousLayout, previousPreviousLayout);
 }
+bool SequenceLayout::moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) {
+  // If the cursor is inside the upper bound, move it to the lower bound.
+  if (m_upperBoundLayout && previousLayout == m_upperBoundLayout) {
+    assert(m_lowerBoundLayout != nullptr);
+    return m_lowerBoundLayout->moveDownInside(cursor);
+  }
+  // If the cursor is Left of the argument, move it to the lower bound.
+  if (m_argumentLayout
+      && previousLayout == m_argumentLayout
+      && cursor->positionIsEquivalentTo(m_argumentLayout, ExpressionLayoutCursor::Position::Left))
+  {
+    assert(m_lowerBoundLayout != nullptr);
+    return m_lowerBoundLayout->moveDownInside(cursor);
+  }
+  return ExpressionLayout::moveDown(cursor, previousLayout, previousPreviousLayout);
+}
 
 KDSize SequenceLayout::computeSize() {
   KDSize argumentSize = m_argumentLayout->size();

poincare/src/layout/sequence_layout.h

@@ -19,6 +19,7 @@ public:
   bool moveLeft(ExpressionLayoutCursor * cursor) override;
   bool moveRight(ExpressionLayoutCursor * cursor) override;
   bool moveUp(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
+  bool moveDown(ExpressionLayoutCursor * cursor, ExpressionLayout * previousLayout, ExpressionLayout * previousPreviousLayout) override;
 protected:
   constexpr static KDCoordinate k_boundHeightMargin = 2;
   ExpressionLayout * m_lowerBoundLayout;