Ensure that unknown md5 modules are not erroneously detected

Closes #805.

1 files changed, 3 insertions, 0 deletions

diff --git a/src/luarocks/fs/lua.lua b/src/luarocks/fs/lua.lua
index 69c75cec..ede7884a 100644
--- a/src/luarocks/fs/lua.lua
+++ b/src/luarocks/fs/lua.lua
@@ -743,6 +743,8 @@ if not md5.sumhexa and md5.digest then
    end
 end
 
+if md5.sumhexa then
+
 --- Get the MD5 checksum for a file.
 -- @param file string: The file to be computed.
 -- @return string: The MD5 checksum or nil + error
@@ -757,6 +759,7 @@ function fs_lua.get_md5(file)
 end
 
 end
+end
 
 ---------------------------------------------------------------------
 -- POSIX functions