Use this command to convert all of the spaces within a selection or file to tabs. This uses the settings in Settings » Editor » Word wrap/tab settings to determine how the tab character/tab stop should be interpreted.
The conversion is performed such that the formatting will remain the same. This will mean that where there are insufficient spaces to replace with a tab character and retain the same formatting the spaces will be left in place.
If a portion of the file is selected/highlighted only the selected portion is converted, otherwise the complete file is converted.