From ad0d0f6d69a7acd6e99f7858f08b427a28d8f8cc Mon Sep 17 00:00:00 2001
From: Enrico Forestieri <forenr@lyx.org>
Date: Sun, 31 May 2015 00:52:49 +0200
Subject: [PATCH] Really fix bug #9354

---
 src/insets/InsetPreview.cpp | 35 ++++++++++++++++++++++++++++++++---
 1 file changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/insets/InsetPreview.cpp b/src/insets/InsetPreview.cpp
index 1b3456eac9..36e866c37c 100644
--- a/src/insets/InsetPreview.cpp
+++ b/src/insets/InsetPreview.cpp
@@ -24,12 +24,18 @@
 
 #include "graphics/PreviewImage.h"
 
+#include "mathed/MacroTable.h"
+
+#include "support/lstrings.h"
+
 #include <sstream>
 
 using namespace std;
 
 namespace lyx {
 
+using support::prefixIs;
+
 
 InsetPreview::InsetPreview(Buffer * buf) 
 	: InsetText(buf),
@@ -70,10 +76,33 @@ void InsetPreview::preparePreview(DocIterator const & pos) const
 	TexRow texrow;
 	odocstringstream str;
 	otexstream os(str, texrow);
-	OutputParams runparams(&pos.buffer()->params().encoding());
+	Buffer const * buffer = pos.buffer();
+	OutputParams runparams(&buffer->params().encoding());
 	latex(os, runparams);
-	docstring const snippet = str.str();
-	preview_->addPreview(snippet, *pos.buffer());
+	// collect macros at this position in case they are used in a math inset
+	MacroNameSet macros;
+	buffer->listMacroNames(macros);
+	MacroNameSet::iterator it = macros.begin();
+	MacroNameSet::iterator end = macros.end();
+	docstring macro_preamble;
+	for (; it != end; ++it) {
+		MacroData const * data = buffer->getMacro(*it, pos, true);
+		if (data) {
+			odocstringstream macro_def;
+			data->write(macro_def, false);
+			docstring const md = macro_def.str();
+			macro_def << endl;
+			bool is_newcomm = prefixIs(md, from_ascii("\\newcomm"));
+			// assure that \newcommand defs are only added once
+			if (!is_newcomm || !preview_->hasMacroDef(md, *buffer)) {
+				if (is_newcomm)
+					preview_->addMacroDef(md, *buffer);
+				macro_preamble.append(macro_def.str());
+			}
+		}
+	}
+	docstring const snippet = macro_preamble + str.str();
+	preview_->addPreview(snippet, *buffer);
 }
 
 
-- 
2.39.2