Fix bug #6367: Screen jumps around when using undo/redo

[lyx.git] / src / Layout.cpp

diff --git a/src/Layout.cpp b/src/Layout.cpp
index 6861b5b2b24a1f8c17ac9fad8f429f3a6928a1dc..a57a28e813a317f2aa0ca9a5d178124379ac7ab5 100644 (file)
--- a/src/Layout.cpp
+++ b/src/Layout.cpp
@@ -874,13 +874,14 @@ docstring const i18npreamble(Language const * lang, Encoding const & enc,
 #ifdef TEX2LYX
        // tex2lyx does not have getMessages()
        LASSERT(false, /**/);
+       (void)enc;
 #else
        string const langenc = lang->encoding()->iconvName();
        string const texenc = lang->encoding()->latexName();
        string const bufenc = enc.iconvName();
        // First and second character of plane 15 (Private Use Area)
-       char const s1[5] = {0xf3, 0xb0, 0x80, 0x80, 0x00}; // U+F0000
-       char const s2[5] = {0xf3, 0xb0, 0x80, 0x81, 0x00}; // U+F0001
+       string const s1 = "\xf3\xb0\x80\x80"; // U+F0000
+       string const s2 = "\xf3\xb0\x80\x81"; // U+F0001
        // FIXME UNICODE
        // lyx::regex is not unicode-safe.
        // Should use QRegExp or (boost::u32regex, but that requires ICU)
@@ -888,11 +889,19 @@ docstring const i18npreamble(Language const * lang, Encoding const & enc,
        smatch sub;
        while (regex_search(preamble, sub, reg)) {
                string const key = sub.str(1);
-               string translated = to_utf8(lang->translateLayout(key));
-               if (langenc != bufenc)
-                       translated = "\\inputencoding{" + texenc + "}"
-                               + string(s1) + langenc + string(s2) + translated
-                               + string(s1) + bufenc + string(s2);
+               docstring const name = lang->translateLayout(key);
+               // Check whether name can be encoded in the buffer encoding
+               bool encodable = true;
+               for (size_t i = 0; i < name.size(); ++i) {
+                       if (enc.latexChar(name[i], true)[0] != name[i]) {
+                               encodable = false;
+                               break;
+                       }
+               }
+               string const translated = encodable ? to_utf8(name)
+                       : "\\inputencoding{" + texenc + "}"
+                               + s1 + langenc + s2 + to_utf8(name)
+                               + s1 + bufenc + s2;
                preamble = subst(preamble, sub.str(), translated);
        }
 #endif