[LyX/2.3.x] Reset InsetArgument language after passthru status change

[Juergen Spitzmueller]

commit d8c018b8c691f6bc3ebbb5f78bffc0b3f87c228f
Author: Juergen Spitzmueller <sp...@lyx.org>
Date:   Fri Sep 15 16:21:05 2017 +0200

    Reset InsetArgument language after passthru status change
    
    Fixes: #10664
---
 src/insets/InsetArgument.cpp |   28 +++++++++++++++++++++++++++-
 src/insets/InsetArgument.h   |    2 ++
 2 files changed, 29 insertions(+), 1 deletions(-)

diff --git a/src/insets/InsetArgument.cpp b/src/insets/InsetArgument.cpp
index e22bcde..5e51f42 100644
--- a/src/insets/InsetArgument.cpp
+++ b/src/insets/InsetArgument.cpp
@@ -68,6 +68,8 @@ void InsetArgument::updateBuffer(ParIterator const & it, 
UpdateType utype)
                it.inset().getLayout().args() : it.paragraph().layout().args();
        pass_thru_context_ = insetlayout ?
                it.inset().getLayout().isPassThru() : 
it.paragraph().layout().pass_thru;
+       // Record PassThru status in order to act on changes.
+       bool const former_pass_thru = pass_thru_;
 
        // Handle pre 2.1 ArgInsets (lyx2lyx cannot classify them)
        if (name_ == "999") {
@@ -139,6 +141,16 @@ void InsetArgument::updateBuffer(ParIterator const & it, 
UpdateType utype)
                labelstring_ = _("Unknown Argument");
                tooltip_ = _("Argument not known in this Layout. Will be 
supressed in the output.");
        }
+
+       if (former_pass_thru != pass_thru_) {
+               // PassThru status changed. We might need to update
+               // the language of the contents
+               Language const * l  = insetlayout
+                       ? it.inset().buffer().language()
+                       : it.buffer()->language();
+               fixParagraphLanguage(l);
+       }
+
        setButtonLabel();
        InsetCollapsable::updateBuffer(it, utype);
 }
@@ -187,8 +199,13 @@ void InsetArgument::doDispatch(Cursor & cur, FuncRequest & 
cmd)
                // forcing to latex_language in InsetText::dispatch(),
                // since this does not play nicely with inherited pass_thru
                // (see #8471).
-               if (pass_thru_ && !pass_thru_local_)
+               if (pass_thru_ && !pass_thru_local_) {
                        text().dispatch(cur, cmd);
+                       // For the paste operations, check if we have
+                       // non-latex_language, and if so, fix.
+                       if (cmd.action() != LFUN_SELF_INSERT)
+                               
fixParagraphLanguage(buffer().params().language);
+               }
                else
                        InsetCollapsable::doDispatch(cur, cmd);
                break;
@@ -322,4 +339,13 @@ void InsetArgument::addToToc(DocIterator const & dit, bool 
output_active,
 }
 
 
+void InsetArgument::fixParagraphLanguage(Language const * l)
+{
+       Font font(inherit_font, l);
+       if (pass_thru_)
+               font.setLanguage(latex_language);
+       paragraphs().front().resetFonts(font);
+}
+
+
 } // namespace lyx
diff --git a/src/insets/InsetArgument.h b/src/insets/InsetArgument.h
index cbd0337..86de5b1 100644
--- a/src/insets/InsetArgument.h
+++ b/src/insets/InsetArgument.h
@@ -92,6 +92,8 @@ private:
        ///
        docstring toolTip(BufferView const & bv, int, int) const;
        ///
+       void fixParagraphLanguage(Language const *);
+       ///
        std::string name_;
        ///
        docstring labelstring_;