[patch] potential fix for #4299

[Andre Poenitz]

Ok?



Index: preamble.cpp
===================================================================
--- preamble.cpp        (revision 26861)
+++ preamble.cpp        (working copy)
@@ -512,7 +512,18 @@
                        static regex const usercommands("User specified LaTeX 
commands");
                        
                        string const comment = t.asInput();
-                       cerr << "Seen comment: " << comment << std::endl;
+                       //cerr << "Seen comment: " << comment << std::endl;
+                       
+                       // magically switch encoding default if it looks like 
XeLaTeX
+                       static string const magicXeLaTeX =
+                               "% This document must be compiled with XeLaTeX 
";
+                       if (comment.size() > magicXeLaTeX.size() 
+                                 && comment.substr(0, magicXeLaTeX.size()) == 
magicXeLaTeX
+                                 && h_inputencoding == "auto") {
+                               cerr << "XeLaTeX comment found, switching to 
UTF8\n";
+                               h_inputencoding = "utf8";
+                       }
+
                        smatch sub;
                        if (regex_search(comment, sub, islyxfile))
                                is_lyx_file = true;