From 4de0a72786f6b04e4814b9236d3ce73109e4feb1 Mon Sep 17 00:00:00 2001
From: itsmattkc <itsmattkc@gmail.com>
Date: Mon, 24 May 2021 16:04:46 +1000
Subject: [PATCH] rational: don't flip if null

Fixes issue where flipped rationals would erroneously create a NaN.

Fixes #1641
Fixes #1642
---
 app/common/rational.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/app/common/rational.cpp b/app/common/rational.cpp
index 8d12a69a1..fd5641047 100644
--- a/app/common/rational.cpp
+++ b/app/common/rational.cpp
@@ -142,7 +142,9 @@ rational rational::flipped() const
 
 void rational::flip()
 {
-  std::swap(denom_, numer_);
+  if (!isNull()) {
+    std::swap(denom_, numer_);
+  }
 }
 
 bool rational::isNull() const