tex2lyx: fix bug #7845

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@39954 a592a061-630c-0410-9148-cb99ea01b6c8

diff --git a/src/tex2lyx/preamble.cpp b/src/tex2lyx/preamble.cpp
index dbd51de88273bcca1a06a1abbd334fcfa13bc93f..23d95e8b5a9528af3d5c312a8894a7aa8fe485af 100644 (file)
--- a/src/tex2lyx/preamble.cpp
+++ b/src/tex2lyx/preamble.cpp
@@ -49,7 +49,11 @@ const char * const modules_placeholder = "\001modules\001";
 // needed to handle encodings with babel
 bool one_language = true;
 string h_inputencoding = "auto";
-string h_paragraph_separation    = "indent";
+string h_paragraph_separation = "indent";
+
+// necessary to avoid that our preamble stuff is added at each tex2lyx run
+// which would pollute the preamble when doing roundtrips
+bool ifundefined_color_set = false;
 
 namespace {
 
@@ -525,18 +529,22 @@ void handle_package(Parser &p, string const & name, string const & opts,
        else if (name == "undertilde")
                h_use_undertilde = "2";
 
-       else if (name == "babel" && !opts.empty()) {
-               // check if more than one option was used - used later for inputenc
-               // in case inputenc is parsed before babel, set the encoding to auto
-               if (options.begin() != options.end() - 1) {
-                       one_language = false;
-                       h_inputencoding = "auto";
+       else if (name == "babel") {
+               // we have to do nothing if babel is loaded without any options, otherwise
+               // we would pollute the preamble with this call in every roundtrip
+               if  (!opts.empty()) {
+                       // check if more than one option was used - used later for inputenc
+                       // in case inputenc is parsed before babel, set the encoding to auto
+                       if (options.begin() != options.end() - 1) {
+                               one_language = false;
+                               h_inputencoding = "auto";
+                       }
+                       // babel takes the last language of the option of its \usepackage
+                       // call as document language. If there is no such language option, the
+                       // last language in the documentclass options is used.
+                       handle_opt(options, known_languages, h_language);
+                       delete_opt(options, known_languages);
                }
-               // babel takes the last language of the option of its \usepackage
-               // call as document language. If there is no such language option, the
-               // last language in the documentclass options is used.
-               handle_opt(options, known_languages, h_language);
-               delete_opt(options, known_languages);
        }
 
        else if (name == "fontenc") {
@@ -590,7 +598,9 @@ void handle_package(Parser &p, string const & name, string const & opts,
        else if (name == "color") {
                // with the following command this package is only loaded when needed for
                // undefined colors, since we only support the predefined colors
-               h_preamble << "\\@ifundefined{definecolor}\n {\\usepackage{color}}{}\n";
+               // only add it if not yet added
+               if (!ifundefined_color_set)
+                       h_preamble << "\\@ifundefined{definecolor}\n {\\usepackage{color}}{}\n";
        }
 
        else if (name == "graphicx")
@@ -1195,6 +1205,11 @@ void parse_preamble(Parser & p, ostream & os,
                        // test case \@ifundefined{date}{}{\date{}}
                        if (arg1 == "date" && arg2.empty() && arg3 == "\\date{}") {
                                h_suppress_date = "true";
+                       // test case \@ifundefined{definecolor}{\usepackage{color}}{}
+                       // because we could pollute the preamble with it in roundtrips
+                       } else if (arg1 == "definecolor" && arg2 == "\\usepackage{color}"
+                               && arg3.empty()) {
+                               ifundefined_color_set = true;
                        } else if (!in_lyx_preamble) {
                                h_preamble << t.asInput()
                                           << '{' << arg1 << '}'