revert attempt at sequence compression + cursorUpBy

screen.go

@@ -27,10 +27,6 @@ func cursorDown(w io.Writer) {
 	fmt.Fprintf(w, te.CSI+te.CursorDownSeq, 1)
 }
 
-func cursorUpBy(w io.Writer, count int) {
-	fmt.Fprintf(w, te.CSI+te.CursorUpSeq, count)
-}
-
 func insertLine(w io.Writer, numLines int) {
 	fmt.Fprintf(w, te.CSI+"%dL", numLines)
 }

screen_test.go

@@ -46,13 +46,7 @@ func TestScreen(t *testing.T) {
 			exercise(t, cursorUp, []byte("\x1b[1A"))
 		})
 
-		t.Run("upBy", func(t *testing.T) {
-			exercise(t, func(w io.Writer) {
-				cursorUpBy(w, 3)
-			}, []byte("\x1b[3A"))
-		})
-
-		t.Run("downBy", func(t *testing.T) {
+		t.Run("down", func(t *testing.T) {
 			exercise(t, cursorDown, []byte("\x1b[1B"))
 		})
 

standard_renderer.go

@@ -138,23 +138,17 @@ func (r *standardRenderer) flush() {
 
 	// Clear any lines we painted in the last render.
 	if r.linesRendered > 0 {
-		jumpedLines := 0
 		for i := r.linesRendered - 1; i > 0; i-- {
 			// If the number of lines we want to render hasn't increased and
 			// new line is the same as the old line we can skip rendering for
 			// this line as a performance optimization.
 			if (len(newLines) <= len(oldLines)) && (len(newLines) > i && len(oldLines) > i) && (newLines[i] == oldLines[i]) {
 				skipLines[i] = struct{}{}
-				jumpedLines++
-			} else {
-				cursorUpBy(out, jumpedLines)
+			} else if _, exists := r.ignoreLines[i]; !exists {
 				clearLine(out)
-
-				jumpedLines = 0
 			}
-		}
-		if jumpedLines >= 1 {
-			cursorUpBy(out, jumpedLines+1)
+
+			cursorUp(out)
 		}
 
 		if _, exists := r.ignoreLines[0]; !exists {