This is needed for ease of column shifting.

Very simillar to the one with IRow.

…r class

These update formulas according to the new positions of the columns. Simillar to UpdateRowFormulas and  ShiftFormula for IRow.

Add SheetUtil.CopyColumn method
Simillar to SheetUtil.CopyRow.

Implement column related methods in XSSFSheet

…ncluded in the column

And delete it from there too.

…tself.

… fields into individual "CT_Col"s

This drastically hinders performance if used with ColumnHelper in its current state, so it needs to be deprecated and it;s functionality replaced with XSSFColumn.

XSSFColumn is changing it's cell storage to a dynamically generated from rows, so there is no more need for a double check.

…edSpecifiedField to false.

Doesnt make any sense for them to be true by default. OOXLM XSD specifies collapsed attribute as false by default too.

It used to hold all cells in its own list. Now it just looks them up from rows.

These methods now use XSSFColumn to perform their tasks.

…he values after save and reload

…and collapsed properites into their fields, to not trigger setters.

…larity before writing CT_Cols node.

This will make sure the CT_Cols follow the excel's rules of storing these objects, where adjscent columns with equal attributes will be combines into CT_Col spans.

Tests are specifically designed to check that the merged regions are treated correctly during shift

… merged regions

Bug was that lastCol was almost always 0, thus the check for the removal of the merged region will return false and regions will stay in place

…index

…Shifter.ShiftMergedRegions

… area when dealing with merged regions.

Overwritten area is the one where the row/column will be, once moved

add first row/column of numbers to see what row/column moved where and where from

it was unneseccarily creating all columns, not just the ones that need clearing

these test would have fail in cultures with different decimal delimiters etc

it was moving cells to the columns that were then also shifted, shifting these cells extra times

…ber of columns. Only init columns that have data

…kUpCtCol` method

…implementations

…nWidth method