From 70adaebb1d8d38c9851b4de1c846441d753c8152 Mon Sep 17 00:00:00 2001
From: Guillaume Nodet <gnodet@gmail.com>
Date: Tue, 1 Dec 2020 13:58:38 +0100
Subject: [PATCH] Check values when emitting ansi sequences for cursor
 movement, fixes #172

---
 src/main/java/org/fusesource/jansi/Ansi.java | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/main/java/org/fusesource/jansi/Ansi.java b/src/main/java/org/fusesource/jansi/Ansi.java
index 7aef8d1d..fa1ea97d 100644
--- a/src/main/java/org/fusesource/jansi/Ansi.java
+++ b/src/main/java/org/fusesource/jansi/Ansi.java
@@ -523,7 +523,7 @@ public Ansi cursor(final int row, final int column) {
     }
 
     public Ansi cursorToColumn(final int x) {
-        return appendEscapeSequence('G', x);
+        return x >= 0 ? appendEscapeSequence('G', x) : this;
     }
 
     public Ansi cursorUp(final int y) {
@@ -531,15 +531,15 @@ public Ansi cursorUp(final int y) {
     }
 
     public Ansi cursorDown(final int y) {
-        return appendEscapeSequence('B', y);
+        return y > 0 ? appendEscapeSequence('B', y) : this;
     }
 
     public Ansi cursorRight(final int x) {
-        return appendEscapeSequence('C', x);
+        return x > 0 ? appendEscapeSequence('C', x) : this;
     }
 
     public Ansi cursorLeft(final int x) {
-        return appendEscapeSequence('D', x);
+        return x > 0 ? appendEscapeSequence('D', x) : this;
     }
 
     public Ansi cursorDownLine() {
@@ -547,7 +547,7 @@ public Ansi cursorDownLine() {
     }
 
     public Ansi cursorDownLine(final int n) {
-        return appendEscapeSequence('E', n);
+        return n > 0 ? appendEscapeSequence('E', n) : this;
     }
 
     public Ansi cursorUpLine() {
@@ -555,7 +555,7 @@ public Ansi cursorUpLine() {
     }
 
     public Ansi cursorUpLine(final int n) {
-        return appendEscapeSequence('F', n);
+        return n > 0 ? appendEscapeSequence('F', n) : this;
     }
 
     public Ansi eraseScreen() {
@@ -575,11 +575,11 @@ public Ansi eraseLine(final Erase kind) {
     }
 
     public Ansi scrollUp(final int rows) {
-        return appendEscapeSequence('S', rows);
+        return rows > 0 ? appendEscapeSequence('S', rows) : this;
     }
 
     public Ansi scrollDown(final int rows) {
-        return appendEscapeSequence('T', rows);
+        return rows > 0 ? appendEscapeSequence('T', rows) : this;
     }
 
     public Ansi saveCursorPosition() {