[LyX/2.3.2-staging] tex2lyx: honor grouping in optional arguments.

[Juergen Spitzmueller]

commit 590185d3ef903714090c0461d4e1c427679a2833
Author: Juergen Spitzmueller <sp...@lyx.org>
Date:   Fri Mar 9 13:14:13 2018 +0100

    tex2lyx: honor grouping in optional arguments.
    
    E.g., \cite[{a literal ] character}]{key}
    
    (cherry picked from commit cba38881d6b9fa3ff5dd0ebe50239fc384309082)
---
 src/tex2lyx/Parser.cpp |   16 ++++++++++++++--
 1 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/tex2lyx/Parser.cpp b/src/tex2lyx/Parser.cpp
index 35748b9..6e29623 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();