[patch] Fix bug 2667

[Georg Baum]

This patch fixes bug 2667 (see 
http://bugzilla.lyx.org/show_bug.cgi?id=2667). It will go in trunk 
tomorrow if nobody objects. I will then also set the target to 1.4.3 and 
attach a patch for 1.4 in bugzilla.
I propose to do that with all 1.4 bugs that get fixed during Jean-Marcs 
vacation.


Georg

Log:
Fix bug 2667
        * src/tex2lyx/tex2lyx.C
        (tex2lyx): output an empty paragraph if the document is empty

        * src/tex2lyx/context.C
        (Context::check_layout): set empty to false

        * src/tex2lyx/context.[Ch]
        (empty): new flag, tells whether all contexts are empty

Index: src/tex2lyx/tex2lyx.C
===================================================================
--- src/tex2lyx/tex2lyx.C	(Revision 14461)
+++ src/tex2lyx/tex2lyx.C	(Arbeitskopie)
@@ -413,6 +413,9 @@ void tex2lyx(std::istream &is, std::ostr
 	active_environments.push_back("document");
 	Context context(true, textclass);
 	parse_text(p, ss, FLAG_END, true, context);
+	if (Context::empty)
+		// Empty document body. LyX needs at least one paragraph.
+		context.check_layout(ss);
 	context.check_end_layout(ss);
 	ss << "\n\\end_body\n\\end_document\n";
 	active_environments.pop_back();
Index: src/tex2lyx/context.C
===================================================================
--- src/tex2lyx/context.C	(Revision 14461)
+++ src/tex2lyx/context.C	(Arbeitskopie)
@@ -77,6 +77,7 @@ void output_font_change(ostream & os, Fo
 
 
 Font Context::normalfont;
+bool Context::empty = true;
 
 
 Context::Context(bool need_layout_,
@@ -145,6 +146,7 @@ void Context::check_layout(ostream & os)
 			extra_stuff.erase();
 		}
 		os << "\n";
+		empty = false;
 	}
 }
 
Index: src/tex2lyx/context.h
===================================================================
--- src/tex2lyx/context.h	(Revision 14461)
+++ src/tex2lyx/context.h	(Arbeitskopie)
@@ -133,6 +133,8 @@ public:
 	 * would not work.
 	 */
 	bool new_layout_allowed;
+	/// Did we output anything yet in any context?
+	static bool empty;
 
 	/// The textclass of the document. Could actually be a global variable
 	LyXTextClass const & textclass;