From c4d97e4c44bf4c70fdbb35bd1ca06c38b0a1ded3 Mon Sep 17 00:00:00 2001
From: Nick Schonning <nschonni@gmail.com>
Date: Wed, 17 Jul 2019 04:33:48 -0400
Subject: [PATCH] fix: str-slice can't start at 0

See https://github.com/sass/sass-spec/pull/1441
Closes #2920
---
 src/fn_strings.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/fn_strings.cpp b/src/fn_strings.cpp
index b09fce9a6c..b30e7bf275 100644
--- a/src/fn_strings.cpp
+++ b/src/fn_strings.cpp
@@ -185,7 +185,7 @@ namespace Sass {
         if (end_at > size) { end_at = (double)size; }
         if (start_at < 0) {
           start_at += size + 1;
-          if (start_at < 0)  start_at = 0;
+          if (start_at <= 0) start_at = 1;
         }
         else if (start_at == 0) { ++ start_at; }