From e9cb08e74cc234b743dfb720d1e25b6777a8724d Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Wed, 12 Feb 2020 20:34:20 -0800
Subject: [PATCH] sample.lua - fix error message.

image_format not img_format.

Closes #6135.
---
 data/sample.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/data/sample.lua b/data/sample.lua
index c33be7e92..5752d2684 100644
--- a/data/sample.lua
+++ b/data/sample.lua
@@ -33,7 +33,7 @@ local image_mime_type = ({
     png = "image/png",
     svg = "image/svg+xml",
   })[image_format]
-  or error("unsupported image format `" .. img_format .. "`")
+  or error("unsupported image format `" .. image_format .. "`")
 
 -- Character escaping
 local function escape(s, in_attribute)