From 2c304b2bdd6cf1d894a51aec4d49635c6e547745 Mon Sep 17 00:00:00 2001
From: "Veronica K. B. Olsen" <1619840+vkbo@users.noreply.github.com>
Date: Mon, 8 Jun 2020 09:21:08 +0200
Subject: [PATCH] Made the doc viewer more fail tolerant

---
 nw/gui/docviewer.py | 21 ++++++++++++++++-----
 1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/nw/gui/docviewer.py b/nw/gui/docviewer.py
index 3c4f86b9..0624a321 100644
--- a/nw/gui/docviewer.py
+++ b/nw/gui/docviewer.py
@@ -135,11 +135,22 @@ class GuiDocViewer(QTextBrowser):
         aDoc = ToHtml(self.theProject, self.theParent)
         aDoc.setPreview(True, self.mainConf.viewComments)
         aDoc.setLinkHeaders(True)
-        aDoc.setText(tHandle)
-        aDoc.doAutoReplace()
-        aDoc.tokenizeText()
-        aDoc.doConvert()
-        aDoc.doPostProcessing()
+
+        # Be extra careful here to prevent crashes when first opening a
+        # project as a crash here leaves no way of recovering.
+        # See issue #298
+        try:
+            aDoc.setText(tHandle)
+            aDoc.doAutoReplace()
+            aDoc.tokenizeText()
+            aDoc.doConvert()
+            aDoc.doPostProcessing()
+        except Exception as e:
+            logger.error("Failed to generate preview for document with handle '%s'" % tHandle)
+            logger.error(str(e))
+            self.setText("An error occurred while generating the preview.")
+            return False
+
         self.setHtml(aDoc.theResult)
         if self.theHandle == tHandle:
             self.verticalScrollBar().setValue(sPos)