Added hybrid line numbers (#1690)

* Added hybrid line numbers

* Changed rulerhybrid to relativeruler, modified documentation accordingly.

* Reverted go.mod and go.sum
I don't know how they got changed but they are good now.

Co-authored-by: Colin Hughes <semilin@pop-os.localdomain>

internal/config/settings.go

@@ -203,6 +203,7 @@ var defaultCommonSettings = map[string]interface{}{
 	"readonly":       false,
 	"rmtrailingws":   false,
 	"ruler":          true,
+	"relativeruler":  false,
 	"savecursor":     false,
 	"saveundo":       false,
 	"scrollbar":      false,

internal/display/bufwindow.go

@@ -335,7 +335,14 @@ func (w *BufWindow) drawDiffGutter(backgroundStyle tcell.Style, softwrapped bool
 }
 
 func (w *BufWindow) drawLineNum(lineNumStyle tcell.Style, softwrapped bool, maxLineNumLength int, vloc *buffer.Loc, bloc *buffer.Loc) {
-	lineNum := strconv.Itoa(bloc.Y + 1)
+	cursorLine := w.Buf.GetActiveCursor().Loc.Y
+	var lineInt int
+	if w.Buf.Settings["relativeruler"] == false || cursorLine == bloc.Y {
+		lineInt = bloc.Y + 1
+	} else {
+		lineInt = bloc.Y - cursorLine
+	}
+	lineNum := strconv.Itoa(util.Abs(lineInt))
 
 	// Write the spaces before the line number if necessary
 	for i := 0; i < maxLineNumLength-len(lineNum); i++ {

runtime/help/options.md

@@ -214,6 +214,12 @@ Here are the available options:
 
 	default value: `true`
 
+* `relativeruler`: make line numbers display relatively. If set to true, all lines except
+	for the line that the cursor is located will display the distance from the 
+	cursor's line. 
+
+	default value: `false` 
+
 * `savecursor`: remember where the cursor was last time the file was opened and
    put it there when you open the file again. Information is saved to
    `~/.config/micro/buffers/`