From 590185d3ef903714090c0461d4e1c427679a2833 Mon Sep 17 00:00:00 2001
From: Juergen Spitzmueller <spitz@lyx.org>
Date: Fri, 9 Mar 2018 13:14:13 +0100
Subject: [PATCH] tex2lyx: honor grouping in optional arguments.

E.g., \cite[{a literal ] character}]{key}

(cherry picked from commit cba38881d6b9fa3ff5dd0ebe50239fc384309082)
---
 src/tex2lyx/Parser.cpp | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/tex2lyx/Parser.cpp b/src/tex2lyx/Parser.cpp
index 35748b9769..6e29623b96 100644
--- a/src/tex2lyx/Parser.cpp
+++ b/src/tex2lyx/Parser.cpp
@@ -494,6 +494,7 @@ Parser::Arg Parser::getFullArg(char left, char right, bool allow_escaping)
 	if (! good())
 		return make_pair(false, string());
 
+	int group_level = 0;
 	string result;
 	Token t = get_token();
 
@@ -504,6 +505,15 @@ Parser::Arg Parser::getFullArg(char left, char right, bool allow_escaping)
 	} else {
 		while (good()) {
 			t = get_token();
+			// honor grouping
+			if (left != '{' && t.cat() == catBegin) {
+				++group_level;
+				continue;
+			}
+			if (left != '{' && t.cat() == catEnd) {
+				--group_level;
+				continue;
+			}
 			// Ignore comments
 			if (t.cat() == catComment) {
 				if (!t.cs().empty())
@@ -511,13 +521,15 @@ Parser::Arg Parser::getFullArg(char left, char right, bool allow_escaping)
 				continue;
 			}
 			if (allow_escaping) {
-				if (t.cat() != catEscape && t.character() == right)
+				if (t.cat() != catEscape && t.character() == right
+				    && group_level == 0)
 					break;
 			} else {
 				if (t.character() == right) {
 					if (t.cat() == catEscape)
 						result += '\\';
-					break;
+					if (group_level == 0)
+						break;
 				}
 			}
 			result += t.asInput();