[LyX/master] tex2lyx: do not keep the Flex prefix for Flex insets names

[Jean-Marc Lasgouttes]

commit 40a3a44aa26c5b70dfcf9dad0fc388cbca975ffd
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Wed Dec 20 16:00:39 2017 +0100

    tex2lyx: do not keep the Flex prefix for Flex insets names
    
    While there is code in LyX that handles this, tex2lyx should respect
    the format that LyX produces and the Flex: prefix is gone since
    cfeddb92 in 2014.
    
    In particular, this prefix is known to cause assertion when undoing a
    document setting change.
---
 src/tex2lyx/text.cpp |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/tex2lyx/text.cpp b/src/tex2lyx/text.cpp
index 5330c62..f550532 100644
--- a/src/tex2lyx/text.cpp
+++ b/src/tex2lyx/text.cpp
@@ -1994,7 +1994,11 @@ void parse_environment(Parser & p, ostream & os, bool 
outer,
                eat_whitespace(p, os, parent_context, false);
                parent_context.check_layout(os);
                begin_inset(os, "Flex ");
-               os << to_utf8(newinsetlayout->name()) << '\n'
+               docstring flex_name = newinsetlayout->name();
+               // FIXME: what do we do if the prefix is not Flex: ?
+               if (prefixIs(flex_name, from_ascii("Flex:")))
+                       flex_name.erase(0, 5);
+               os << to_utf8(flex_name) << '\n'
                   << "status collapsed\n";
                if (newinsetlayout->isPassThru()) {
                        string const arg = p.verbatimEnvironment(name);
@@ -4803,7 +4807,7 @@ void parse_text(Parser & p, ostream & os, unsigned flags, 
bool outer,
                                p.get_token();
                        p.skip_spaces();
                        context.check_layout(os);
-                       docstring const name = newinsetlayout->name();
+                       docstring name = newinsetlayout->name();
                        bool const caption = name.find(from_ascii("Caption:")) 
== 0;
                        if (caption) {
                                // Already done for floating minted listings.
@@ -4812,6 +4816,9 @@ void parse_text(Parser & p, ostream & os, unsigned flags, 
bool outer,
                                        os << to_utf8(name.substr(8)) << '\n';
                                }
                        } else {
+                               // FIXME: what do we do if the prefix is not 
Flex: ?
+                               if (prefixIs(name, from_ascii("Flex:")))
+                                       name.erase(0, 5);
                                begin_inset(os, "Flex ");
                                os << to_utf8(name) << '\n'
                                   << "status collapsed\n";