Method UpN

internal/buffer/cursor.go:247–269

UpN moves the cursor up N lines (if possible)

(amount int)

// UpN moves the cursor up N lines (if possible)
func (c *Cursor) UpN(amount int) {
	proposedY := c.Y - amount
	if proposedY < 0 {
		proposedY = 0
	} else if proposedY >= len(c.buf.lines) {
		proposedY = len(c.buf.lines) - 1
	}

	bytes := c.buf.LineBytes(proposedY)
	c.X = c.GetCharPosInLine(bytes, c.LastVisualX)

	if c.X > util.CharacterCount(bytes) || (amount < 0 && proposedY == c.Y) {
		c.X = util.CharacterCount(bytes)
		c.StoreVisualX()
	}

	if c.X < 0 || (amount > 0 && proposedY == c.Y) {
		c.X = 0
		c.StoreVisualX()
	}

	c.Y = proposedY
}

// DownN moves the cursor down N lines (if possible)
func (c *Cursor) DownN(amount int) {