Introduce NeedCProtect -1 layout option

It turns out beamer frame does not allow \cprotect and errors if it is
used. Hence we need to prevent it in this context entirely.

lib/layouts/beamer.layout

@@ -553,6 +553,7 @@ Style Frame
 	ExampleBlock,AlertBlock,Bibliography,Quotation,Quote,Verse,Corollary,Definition,Definitions,
 	Example,Examples,Fact,Lemma,Proof,Theorem,LyX-Code
   EndAutoNests
+  NeedCProtect    -1
 End
 
 Style PlainFrame

src/Layout.cpp

@@ -162,6 +162,7 @@ Layout::Layout()
 	inpreamble = false;
 	needprotect = false;
 	needcprotect = false;
+	nocprotect = false;
 	needmboxprotect = false;
 	keepempty = false;
 	font = inherit_font;
@@ -465,9 +466,17 @@ bool Layout::readIgnoreForcelocal(Lexer & lex, TextClass const & tclass,
 			lex >> needprotect;
 			break;
 
-		case LT_NEED_CPROTECT:
+		case LT_NEED_CPROTECT: {
-			lex >> needcprotect;
+			int i;
+			lex >> i;
+			nocprotect = false;
+			needcprotect = false;
+			if (i == -1)
+				nocprotect = true;
+			else if (i == 1)
+				needcprotect = true;
 			break;
+		}
 
 		case LT_NEED_MBOXPROTECT:
 			lex >> needmboxprotect;

src/Layout.h

@@ -400,6 +400,9 @@ public:
 	/** true when the verbatim stuff of this layout needs to be
 	    \cprotect'ed. */
 	bool needcprotect;
+  	/** true when the verbatim stuff of this layout never should be
+	    \cprotect'ed. */
+	bool nocprotect;
 	/** true when specific commands in this paragraph need to be
 	    protected in an \mbox. */
 	bool needmboxprotect;

src/OutputParams.h

@@ -108,6 +108,11 @@ public:
 	*/
 	bool moving_arg = false;
 
+	/** no_cprotect == true means that the layout in which this is
+	 *  does not allow \cprotect'ing.
+	*/
+	bool no_cprotect = false;
+
 	/** intitle == true means that the environment in which the
 	    inset is typeset is part of a title (before a \\maketitle).
 	    Footnotes in such environments have moving arguments.

src/Paragraph.cpp

@@ -1172,6 +1172,7 @@ void Paragraph::Private::latexInset(BufferParams const & bparams,
 			? textinset->hasCProtectContent(runparams.moving_arg)
 			  && !textinset->text().isMainText()
 			  && inset->lyxCode() != BRANCH_CODE
+			  && !runparams.no_cprotect
 			: false;
 		unsigned int count2 = basefont.latexWriteStartChanges(os, bparams,
 						      rp, running_font,
@@ -3014,6 +3015,7 @@ void Paragraph::latex(BufferParams const & bparams,
 					? textinset->hasCProtectContent(runparams.moving_arg)
 					  && !textinset->text().isMainText()
 					  && inInset().lyxCode() != BRANCH_CODE
+					  && !runparams.no_cprotect
 					: false;
 				column += current_font.latexWriteStartChanges(ots, bparams,
 									      runparams, basefont, last_font, false,

src/insets/InsetText.cpp

@@ -500,7 +500,7 @@ void InsetText::latex(otexstream & os, OutputParams const & runparams) const
 			// FIXME UNICODE
 			// FIXME \protect should only be used for fragile
 			//    commands, but we do not provide this information yet.
-			if (hasCProtectContent(runparams.moving_arg)) {
+			if (!runparams.no_cprotect && hasCProtectContent(runparams.moving_arg)) {
 				if (contains(runparams.active_chars, '^')) {
 					// cprotect relies on ^ being on catcode 7
 					os << "\\begingroup\\catcode`\\^=7";

src/output_latex.cpp

@@ -404,7 +404,7 @@ static void finishEnvironment(otexstream & os, OutputParams const & runparams,
 
 
 void TeXEnvironment(Buffer const & buf, Text const & text,
-		    OutputParams const & runparams,
+		    OutputParams const & runparams_in,
 		    pit_type & pit, otexstream & os)
 {
 	ParagraphList const & paragraphs = text.paragraphs();
@@ -415,6 +415,9 @@ void TeXEnvironment(Buffer const & buf, Text const & text,
 	depth_type const current_depth = ipar->params().depth();
 	Length const & current_left_indent = ipar->params().leftIndent();
 
+	OutputParams runparams = runparams_in;
+	runparams.no_cprotect = current_layout.nocprotect;
+
 	// This is for debugging purpose at the end.
 	pit_type const par_begin = pit;
 	for (; pit < runparams.par_end; ++pit) {
@@ -736,7 +739,7 @@ void parStartCommand(Paragraph const & par, otexstream & os,
 {
 	switch (style.latextype) {
 	case LATEX_COMMAND:
-		if (par.needsCProtection(runparams.moving_arg)) {
+		if (!runparams.no_cprotect && par.needsCProtection(runparams.moving_arg)) {
 			if (contains(runparams.active_chars, '^'))
 				// cprotect relies on ^ being on catcode 7
 				os << "\\begingroup\\catcode`\\^=7";
@@ -871,7 +874,7 @@ void TeXOnePar(Buffer const & buf,
 		// the code is different (JMarc)
 		if (style.isCommand()) {
 			os << "}";
-			if (par.needsCProtection(runparams.moving_arg)
+			if (!runparams.no_cprotect && par.needsCProtection(runparams.moving_arg)
 			    && contains(runparams.active_chars, '^'))
 				os << "\\endgroup";
 			if (merged_par)
@@ -1234,7 +1237,7 @@ void TeXOnePar(Buffer const & buf,
 				os << runparams.post_macro;
 				runparams.post_macro.clear();
 			}
-			if (par.needsCProtection(runparams.moving_arg)
+			if (!runparams.no_cprotect && par.needsCProtection(runparams.moving_arg)
 			    && contains(runparams.active_chars, '^'))
 				os << "\\endgroup";
 			if (runparams.encoding != prev_encoding) {
@@ -1405,7 +1408,7 @@ void TeXOnePar(Buffer const & buf,
 			os << runparams.post_macro;
 			runparams.post_macro.clear();
 		}
-		if (par.needsCProtection(runparams.moving_arg)
+		if (!runparams.no_cprotect && par.needsCProtection(runparams.moving_arg)
 		    && contains(runparams.active_chars, '^'))
 			os << "\\endgroup";
 		if (runparams.encoding != prev_encoding) {