From 323e72a50ca5253bdbe1d772f7ecd479de4402b9 Mon Sep 17 00:00:00 2001
From: Gabriel Ozouf <gabriel.ozouf@numworks.com>
Date: Thu, 12 Nov 2020 12:21:06 +0100
Subject: [PATCH] [poincare/matrix_layout] Remove columns with backspace

Allow removing empty columns with backspace, the same way one can remove
empty rows. This allows deleting the internal columns that are not
automatically deleted.

Change-Id: I52def7939257942a8396721d01c4d1531ef90361
---
 poincare/src/matrix_layout.cpp | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/poincare/src/matrix_layout.cpp b/poincare/src/matrix_layout.cpp
index 9300ac148..c57af6126 100644
--- a/poincare/src/matrix_layout.cpp
+++ b/poincare/src/matrix_layout.cpp
@@ -92,20 +92,32 @@ void MatrixLayoutNode::willAddSiblingToEmptyChildAtIndex(int childIndex) {
 }
 
 void MatrixLayoutNode::deleteBeforeCursor(LayoutCursor * cursor) {
-  // Deleting the left empty layout of an empty row deletes the row
+  /* Deleting the left empty layout of an empty row deletes the row, and
+   * deleting the top empty layout of an empty column deletes the column. */
   assert(cursor != nullptr);
   LayoutNode * pointedChild = cursor->layoutNode();
   if (pointedChild->isEmpty()) {
     int indexOfPointedLayout = indexOfChild(pointedChild);
-    if (columnAtChildIndex(indexOfPointedLayout) == 0) {
-      int rowIndex = rowAtChildIndex(indexOfPointedLayout);
+    int columnIndex = columnAtChildIndex(indexOfPointedLayout);
+    int rowIndex = rowAtChildIndex(indexOfPointedLayout);
+    bool deleted = false;
+    if (columnIndex == 0) {
       if (rowIndex < m_numberOfRows - 1 && isRowEmpty(rowIndex) && m_numberOfRows > 2) {
         deleteRowAtIndex(rowIndex);
+        deleted = true;
+      }
+    }
+    if (rowIndex == 0) {
+      if (columnIndex < m_numberOfColumns - 1 && isColumnEmpty(columnIndex) && m_numberOfColumns > 2) {
+        deleteColumnAtIndex(columnIndex);
+        deleted = true;
+      }
+    }
+    if (deleted) {
         assert(indexOfPointedLayout >= 0 && indexOfPointedLayout < m_numberOfColumns*m_numberOfRows);
         cursor->setLayoutNode(childAtIndex(indexOfPointedLayout));
         cursor->setPosition(LayoutCursor::Position::Right);
         return;
-      }
     }
   }
   GridLayoutNode::deleteBeforeCursor(cursor);