X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2Foutput_latex.cpp;h=1185e2d6e343149dbb0e7eddbb740958c9bed6ea;hb=104fdcc9be40df19d50cddad7f8ae9ab63bbf5f7;hp=d515ef488606490cc77a717d64a6a34523638137;hpb=4a481975b6e94fc48a7bdfe776106ba79149e5bc;p=lyx.git

diff --git a/src/output_latex.cpp b/src/output_latex.cpp
index d515ef4886..1185e2d6e3 100644
--- a/src/output_latex.cpp
+++ b/src/output_latex.cpp
@@ -12,6 +12,7 @@
 
 #include "output_latex.h"
 
+#include "BiblioInfo.h"
 #include "Buffer.h"
 #include "BufferParams.h"
 #include "Encoding.h"
@@ -63,7 +64,7 @@ enum OpenEncoding {
 struct OutputState
 {
 	OutputState() : open_encoding_(none), cjk_inherited_(0),
-		        prev_env_language_(0), nest_level_(0)
+		prev_env_language_(nullptr), nest_level_(0)
 	{
 	}
 	OpenEncoding open_encoding_;
@@ -191,7 +192,7 @@ static TeXEnvironmentData prepareEnvironment(Buffer const & buf,
 		pit == paragraphs.begin() ? pit : prev(pit, 1);
 
 	OutputState * state = getOutputState();
-	bool const use_prev_env_language = state->prev_env_language_ != 0
+	bool const use_prev_env_language = state->prev_env_language_ != nullptr
 			&& priorpit->layout().isEnvironment()
 			&& (priorpit->getDepth() > pit->getDepth()
 			    || (priorpit->getDepth() == pit->getDepth()
@@ -304,8 +305,11 @@ static TeXEnvironmentData prepareEnvironment(Buffer const & buf,
 
 	// in multilingual environments, the CJK tags have to be nested properly
 	data.cjk_nested = false;
-	if (data.par_language->encoding()->package() == Encoding::CJK &&
-	    state->open_encoding_ != CJK && pit->isMultiLingual(bparams)) {
+	if (!bparams.useNonTeXFonts
+	    && (bparams.inputenc == "auto-legacy"
+			|| bparams.inputenc == "auto-legacy-plain")
+	    && data.par_language->encoding()->package() == Encoding::CJK
+	    && state->open_encoding_ != CJK && pit->isMultiLingual(bparams)) {
 		if (prev_par_language->encoding()->package() == Encoding::CJK) {
 			os << "\\begin{CJK}{"
 			   << from_ascii(data.par_language->encoding()->latexName())
@@ -430,6 +434,22 @@ void TeXEnvironment(Buffer const & buf, Text const & text,
 			continue;
 		}
 
+		// Do not output empty environments if the whole paragraph has
+		// been deleted with ct and changes are not output.
+		if (size_t(pit + 1) < paragraphs.size()) {
+			ParagraphList::const_iterator nextpar = paragraphs.constIterator(pit + 1);
+			Paragraph const & cpar = paragraphs.at(pit);
+			if ((par->layout() != nextpar->layout()
+			     || par->params().depth() == nextpar->params().depth()
+			     || par->params().leftIndent() == nextpar->params().leftIndent())
+			    && !runparams.for_search && cpar.size() > 0
+			    && cpar.isDeleted(0, cpar.size()) && !buf.params().output_changes) {
+				if (!buf.params().output_changes && !cpar.parEndChange().deleted())
+					os << '\n' << '\n';
+				continue;
+			}
+		}
+
 		// This is a new environment.
 		TeXEnvironmentData const data =
 			prepareEnvironment(buf, text, par, os, runparams);
@@ -675,8 +695,12 @@ void parStartCommand(Paragraph const & par, otexstream & os,
 {
 	switch (style.latextype) {
 	case LATEX_COMMAND:
-		if (par.needsCProtection(runparams.moving_arg))
+		if (par.needsCProtection(runparams.moving_arg)) {
+			if (contains(runparams.active_chars, '^'))
+				// cprotect relies on ^ being on catcode 7
+				os << "\\begingroup\\catcode`\\^=7";
 			os << "\\cprotect";
+		}
 		os << '\\' << from_ascii(style.latexname());
 
 		// Command arguments
@@ -734,12 +758,18 @@ void TeXOnePar(Buffer const & buf,
 	if (style.inpreamble && !force)
 		return;
 
+	// Do not output empty commands if the whole paragraph has
+	// been deleted with ct and changes are not output.
+	if (!runparams_in.for_search && style.latextype != LATEX_ENVIRONMENT
+	    && par.size() > 0 && par.isDeleted(0, par.size()) && !bparams.output_changes)
+		return;
+
 	LYXERR(Debug::LATEX, "TeXOnePar for paragraph " << pit << " ptr " << &par << " '"
 		<< everypar << "'");
 
 	OutputParams runparams = runparams_in;
 	runparams.isLastPar = (pit == pit_type(paragraphs.size() - 1));
-	// We reinitialze par begin and end to be on the safe side
+	// We reinitialize par begin and end to be on the safe side
 	// with embedded inset as we don't know if they set those
 	// value correctly.
 	runparams.par_begin = 0;
@@ -755,11 +785,14 @@ void TeXOnePar(Buffer const & buf,
 		state->open_encoding_ = none;
 	}
 
+	// This paragraph is merged and we do not show changes in the output
+	bool const merged_par = !bparams.output_changes && par.parEndChange().deleted();
+
 	if (text.inset().isPassThru()) {
 		Font const outerfont = text.outerFont(pit);
 
 		// No newline before first paragraph in this lyxtext
-		if (pit > 0) {
+		if (pit > 0 && !text.inset().getLayout().parbreakIgnored() && !merged_par) {
 			os << '\n';
 			if (!text.inset().getLayout().parbreakIsNewline())
 				os << '\n';
@@ -770,13 +803,23 @@ void TeXOnePar(Buffer const & buf,
 	}
 
 	Paragraph const * nextpar = runparams.isLastPar
-		? 0 : &paragraphs.at(pit + 1);
+		? nullptr : &paragraphs.at(pit + 1);
 
-	bool const intitle_command = style.intitle && style.latextype == LATEX_COMMAND;
+	bool const intitle_command = style.intitle && style.isCommand();
+	// Intitle commands switch languages locally, thus increase
+	// language nesting level
+	if (intitle_command)
+		state->nest_level_ += 1;
 
 	if (style.pass_thru) {
 		Font const outerfont = text.outerFont(pit);
 		parStartCommand(par, os, runparams, style);
+		if (style.isCommand() && style.needprotect)
+			// Due to the moving argument, some fragile
+			// commands (labels, index entries)
+			// are output after this command (#2154)
+			runparams.postpone_fragile_stuff =
+				bparams.postpone_fragile_content;
 		if (intitle_command)
 			os << '{';
 
@@ -785,17 +828,25 @@ void TeXOnePar(Buffer const & buf,
 		// I did not create a parEndCommand for this minuscule
 		// task because in the other user of parStartCommand
 		// the code is different (JMarc)
-		if (style.isCommand())
-			os << "}\n";
-		else
+		if (style.isCommand()) {
+			os << "}";
+			if (par.needsCProtection(runparams.moving_arg)
+			    && contains(runparams.active_chars, '^'))
+				os << "\\endgroup";
+			if (merged_par)
+				os << "{}";
+			else
+				os << "\n";
+		}
+		else if (!merged_par)
 			os << '\n';
-		if (!style.parbreak_is_newline) {
+		if (!style.parbreak_is_newline && !merged_par) {
 			os << '\n';
 		} else if (nextpar && !style.isEnvironment()) {
 			Layout const nextstyle = text.inset().forcePlainLayout()
 				? bparams.documentClass().plainLayout()
 				: nextpar->layout();
-			if (nextstyle.name() != style.name())
+			if (nextstyle.name() != style.name() && !merged_par)
 				os << '\n';
 		}
 
@@ -805,16 +856,16 @@ void TeXOnePar(Buffer const & buf,
 	// This paragraph's language
 	Language const * const par_language = par.getParLanguage(bparams);
 	Language const * const nextpar_language = nextpar ?
-		nextpar->getParLanguage(bparams) : 0;
+		nextpar->getParLanguage(bparams) : nullptr;
 	// The document's language
 	Language const * const doc_language = bparams.language;
 	// The language that was in effect when the environment this paragraph is
 	// inside of was opened
 	Language const * const outer_language =
-		(runparams.local_font != 0) ?
+		(runparams.local_font != nullptr) ?
 			runparams.local_font->language() : doc_language;
 
-	Paragraph const * priorpar = (pit == 0) ? 0 : &paragraphs.at(pit - 1);
+	Paragraph const * priorpar = (pit == 0) ? nullptr : &paragraphs.at(pit - 1);
 
 	// The previous language that was in effect is the language of the
 	// previous paragraph, unless the previous paragraph is inside an
@@ -824,19 +875,36 @@ void TeXOnePar(Buffer const & buf,
 	// Note further that we take the outer language also if the prior par
 	// is PassThru, since in that case it has latex_language, and all secondary
 	// languages have been closed (#10793).
-	bool const use_prev_env_language = state->prev_env_language_ != 0
+	bool const use_prev_env_language = state->prev_env_language_ != nullptr
 			&& priorpar
 			&& priorpar->layout().isEnvironment()
 			&& (priorpar->getDepth() > par.getDepth()
 			    || (priorpar->getDepth() == par.getDepth()
-				    && priorpar->layout() != par.layout()));
+				&& priorpar->layout() != par.layout()));
+
+	// We need to ignore previous intitle commands since languages
+	// are switched locally there (# 11514)
+	// There might be paragraphs before the title, so we check this.
+	Paragraph * prior_nontitle_par = nullptr;
+	if (!intitle_command) {
+		pit_type ppit = pit;
+		while (ppit > 0) {
+			--ppit;
+			Paragraph const * tmppar = &paragraphs.at(ppit);
+			if (tmppar->layout().intitle && tmppar->layout().isCommand())
+				continue;
+			prior_nontitle_par = const_cast<Paragraph*>(tmppar);
+			break;
+		}
+	}
 	Language const * const prev_language =
-		runparams_in.for_search ?
-			languages.getLanguage("ignore")
-		:(priorpar && !priorpar->isPassThru())
-			? (use_prev_env_language ? state->prev_env_language_
-					 	: priorpar->getParLanguage(bparams))
-			: outer_language;
+		runparams_in.for_search 
+			? languages.getLanguage("ignore")
+			: (prior_nontitle_par && !prior_nontitle_par->isPassThru())
+				? (use_prev_env_language 
+					? state->prev_env_language_
+					: prior_nontitle_par->getParLanguage(bparams))
+				: outer_language;
 
 	bool const use_polyglossia = runparams.use_polyglossia;
 	string const par_lang = use_polyglossia ?
@@ -861,6 +929,12 @@ void TeXOnePar(Buffer const & buf,
 	// (see #10849); thus open the command here.
 	if (intitle_command) {
 		parStartCommand(par, os, runparams, style);
+		if (style.isCommand() && style.needprotect)
+			// Due to the moving argument, some fragile
+			// commands (labels, index entries)
+			// are output after this command (#2154)
+			runparams.postpone_fragile_stuff =
+				bparams.postpone_fragile_content;
 		os << '{';
 	}
 
@@ -870,13 +944,15 @@ void TeXOnePar(Buffer const & buf,
 	// languages (see # 10111).
 	bool const in_polyglossia_rtl_env =
 		use_polyglossia
-		&& runparams.local_font != 0
+		&& runparams.local_font != nullptr
 		&& outer_language->rightToLeft()
 		&& !par_language->rightToLeft();
-	bool const localswitch = runparams_in.for_search
+	bool const localswitch =
+			(runparams_in.for_search
 			|| text.inset().forceLocalFontSwitch()
 			|| (using_begin_end && text.inset().forcePlainLayout())
-			|| in_polyglossia_rtl_env;
+			|| in_polyglossia_rtl_env)
+			&& !text.inset().forceParDirectionSwitch();
 	if (localswitch) {
 		lang_begin_command = use_polyglossia ?
 			    "\\text$$lang$$opts{" : lyxrc.language_command_local;
@@ -926,7 +1002,7 @@ void TeXOnePar(Buffer const & buf,
 			    && par_language->lang() != "arabic_arabtex"
 			    && outer_language->lang() != "arabic_arabtex"
 			    // are we in an inset?
-			    && runparams.local_font != 0
+			    && runparams.local_font != nullptr
 			    // is the inset within an \L or \R?
 			    //
 			    // FIXME: currently, we don't check this; this means that
@@ -953,8 +1029,10 @@ void TeXOnePar(Buffer const & buf,
 					os << "\\L{";
 			}
 			// With CJK, the CJK tag has to be closed first (see below)
-			if ((runparams.encoding->package() != Encoding::CJK || runparams.for_search)
-			    && (par_lang != openLanguageName(state) || localswitch)
+			if ((runparams.encoding->package() != Encoding::CJK
+				 || bparams.useNonTeXFonts
+				 || runparams.for_search)
+			    && (par_lang != openLanguageName(state) || localswitch || intitle_command)
 			    && !par_lang.empty()) {
 				string bc = use_polyglossia ?
 					  getPolyglossiaBegin(lang_begin_command, par_lang,
@@ -969,11 +1047,12 @@ void TeXOnePar(Buffer const & buf,
 		}
 	}
 
-	// Switch file encoding if necessary; no need to do this for "default"
+	// Switch file encoding if necessary; no need to do this for "auto-legacy-plain"
 	// encoding, since this only affects the position of the outputted
 	// \inputencoding command; the encoding switch will occur when necessary
-	if (bparams.inputenc == "auto"
+	if (bparams.inputenc == "auto-legacy"
 		&& !runparams.isFullUnicode() // Xe/LuaTeX use one document-wide encoding  (see also switchEncoding())
+		&& runparams.encoding->package() != Encoding::japanese
 		&& runparams.encoding->package() != Encoding::none) {
 		// Look ahead for future encoding changes.
 		// We try to output them at the beginning of the paragraph,
@@ -1019,12 +1098,7 @@ void TeXOnePar(Buffer const & buf,
 				if (runparams.encoding->package() == Encoding::CJK
 				    && par_lang != openLanguageName(state)
 				    && !par_lang.empty()) {
-				    	string bc = use_polyglossia ?
-						    getPolyglossiaBegin(lang_begin_command, par_lang,
-						    			par_language->polyglossiaOpts(),
-						    			localswitch)
-						    : subst(lang_begin_command, "$$lang", par_lang);
-					os << bc
+					os << subst(lang_begin_command, "$$lang", par_lang)
 					   << lang_command_termination;
 					if (using_begin_end)
 						pushLanguageName(par_lang, localswitch);
@@ -1071,8 +1145,15 @@ void TeXOnePar(Buffer const & buf,
 
 	// For InTitle commands, we already started the command before
 	// the language switch
-	if (!intitle_command)
+	if (!intitle_command) {
 		parStartCommand(par, os, runparams, style);
+		if (style.isCommand() && style.needprotect)
+			// Due to the moving argument, some fragile
+			// commands (labels, index entries)
+			// are output after this command (#2154)
+			runparams.postpone_fragile_stuff =
+				bparams.postpone_fragile_content;
+	}
 
 	Font const outerfont = text.outerFont(pit);
 
@@ -1092,6 +1173,15 @@ void TeXOnePar(Buffer const & buf,
 			os << '}';
 			if (!style.postcommandargs().empty())
 				latexArgInsets(par, os, runparams, style.postcommandargs(), "post:");
+			if (!runparams.post_macro.empty()) {
+				// Output the stored fragile commands (labels, indices etc.)
+				// that need to be output after the command with moving argument.
+				os << runparams.post_macro;
+				runparams.post_macro.clear();
+			}
+			if (par.needsCProtection(runparams.moving_arg)
+			    && contains(runparams.active_chars, '^'))
+				os << "\\endgroup";
 			if (runparams.encoding != prev_encoding) {
 				runparams.encoding = prev_encoding;
 				os << setEncoding(prev_encoding->iconvName());
@@ -1111,10 +1201,10 @@ void TeXOnePar(Buffer const & buf,
 			    && nextpar->getDepth() < par.getDepth()))
 			close_lang_switch = using_begin_end;
 		if (nextpar && par.params().depth() < nextpar->params().depth())
-			pending_newline = true;
+			pending_newline = !text.inset().getLayout().parbreakIgnored() && !merged_par;
 		break;
 	case LATEX_ENVIRONMENT: {
-		// if its the last paragraph of the current environment
+		// if it's the last paragraph of the current environment
 		// skip it otherwise fall through
 		if (nextpar
 		    && ((nextpar->layout() != par.layout()
@@ -1130,7 +1220,7 @@ void TeXOnePar(Buffer const & buf,
 	default:
 		// we don't need it for the last paragraph and in InTitle commands!!!
 		if (nextpar && !intitle_command)
-			pending_newline = true;
+			pending_newline = !text.inset().getLayout().parbreakIgnored() && !merged_par;
 	}
 
 	// InTitle commands use switches (not environments) for space settings
@@ -1159,7 +1249,7 @@ void TeXOnePar(Buffer const & buf,
 		&& (par_language->lang() != "arabic_arabtex"
 		    && outer_language->lang() != "arabic_arabtex")
 		// have we opened an \L or \R environment?
-		&& runparams.local_font != 0
+		&& runparams.local_font != nullptr
 		&& runparams.local_font->isRightToLeft() != par_language->rightToLeft()
 		// are we about to close the language?
 		&&((nextpar && par_lang != nextpar_lang)
@@ -1168,7 +1258,7 @@ void TeXOnePar(Buffer const & buf,
 	if (localswitch_needed
 	    || (intitle_command && using_begin_end)
 	    || closing_rtl_ltr_environment
-	    || ((runparams.isLastPar || close_lang_switch)
+	    || (((runparams.isLastPar && !runparams.inbranch) || close_lang_switch)
 	        && (par_lang != outer_lang || (using_begin_end
 						&& style.isEnvironment()
 						&& par_lang != nextpar_lang)))) {
@@ -1180,7 +1270,9 @@ void TeXOnePar(Buffer const & buf,
 			os << '\n';
 
 		// when the paragraph uses CJK, the language has to be closed earlier
-		if ((font.language()->encoding()->package() != Encoding::CJK) || runparams_in.for_search) {
+		if ((font.language()->encoding()->package() != Encoding::CJK)
+			|| bparams.useNonTeXFonts
+			|| runparams_in.for_search) {
 			if (lang_end_command.empty()) {
 				// If this is a child, we should restore the
 				// master language after the last paragraph.
@@ -1199,7 +1291,8 @@ void TeXOnePar(Buffer const & buf,
 									localswitch)
 						  : subst(lang_begin_command, "$$lang", current_lang);
 					os << bc;
-					pending_newline = !localswitch;
+					pending_newline = !localswitch
+							&& !text.inset().getLayout().parbreakIgnored();
 					unskip_newline = !localswitch;
 					if (using_begin_end)
 						pushLanguageName(current_lang, localswitch);
@@ -1229,7 +1322,8 @@ void TeXOnePar(Buffer const & buf,
 						lang_end_command,
 						"$$lang",
 						par_lang));
-					pending_newline = !localswitch;
+					pending_newline = !localswitch
+							&& !text.inset().getLayout().parbreakIgnored();
 					unskip_newline = !localswitch;
 					if (using_begin_end)
 						popLanguageName();
@@ -1242,20 +1336,35 @@ void TeXOnePar(Buffer const & buf,
 
 	// InTitle commands need to be closed after the language has been closed.
 	if (intitle_command) {
-		if (is_command) {
-			os << '}';
-			if (!style.postcommandargs().empty())
-				latexArgInsets(par, os, runparams, style.postcommandargs(), "post:");
-			if (runparams.encoding != prev_encoding) {
-				runparams.encoding = prev_encoding;
-				os << setEncoding(prev_encoding->iconvName());
-			}
+		os << '}';
+		if (!style.postcommandargs().empty())
+			latexArgInsets(par, os, runparams, style.postcommandargs(), "post:");
+		if (!runparams.post_macro.empty()) {
+			// Output the stored fragile commands (labels, indices etc.)
+			// that need to be output after the command with moving argument.
+			os << runparams.post_macro;
+			runparams.post_macro.clear();
+		}
+		if (par.needsCProtection(runparams.moving_arg)
+		    && contains(runparams.active_chars, '^'))
+			os << "\\endgroup";
+		if (runparams.encoding != prev_encoding) {
+			runparams.encoding = prev_encoding;
+			os << setEncoding(prev_encoding->iconvName());
 		}
 	}
 
 	bool const last_was_separator =
 		par.size() > 0 && par.isEnvSeparator(par.size() - 1);
 
+	// Signify added/deleted par break in output if show changes in output
+	if (nextpar && !os.afterParbreak() && !last_was_separator
+	    && bparams.output_changes && par.parEndChange().changed()) {
+		Changes::latexMarkChange(os, bparams, Change(Change::UNCHANGED),
+					 par.parEndChange(), runparams);
+		os << bparams.encoding().latexString(docstring(1, 0x00b6)).first << "}";
+	}
+
 	if (pending_newline) {
 		if (unskip_newline)
 			// prevent unwanted whitespace
@@ -1266,11 +1375,12 @@ void TeXOnePar(Buffer const & buf,
 
 	// if this is a CJK-paragraph and the next isn't, close CJK
 	// also if the next paragraph is a multilingual environment (because of nesting)
-	if (nextpar
-		&& (state->open_encoding_ == CJK && bparams.encoding().iconvName() != "UTF-8"
-			&& bparams.encoding().package() != Encoding::CJK )
-		&& (nextpar_language->encoding()->package() != Encoding::CJK
-		   || (nextpar->layout().isEnvironment() && nextpar->isMultiLingual(bparams)))
+	if (nextpar && state->open_encoding_ == CJK
+		&& bparams.encoding().iconvName() != "UTF-8"
+		&& bparams.encoding().package() != Encoding::CJK
+		&& ((nextpar_language &&
+			nextpar_language->encoding()->package() != Encoding::CJK)
+			|| (nextpar->layout().isEnvironment() && nextpar->isMultiLingual(bparams)))
 		// inbetween environments, CJK has to be closed later (nesting!)
 		&& (!style.isEnvironment() || !nextpar->layout().isEnvironment())) {
 		os << "\\end{CJK}\n";
@@ -1297,6 +1407,12 @@ void TeXOnePar(Buffer const & buf,
 				break;
 			}
 			case inputenc: {
+				// FIXME: If we are in an inset and the switch happened outside this inset,
+				// do not switch back at the end of the inset (bug #8479)
+				// The following attempt does not help with listings-caption in a CJK document:
+				// if (runparams_in.local_font != 0
+				//    && runparams_in.encoding == runparams_in.local_font->language()->encoding())
+				//	break;
 				os << "\\egroup";
 				state->open_encoding_ = none;
 				break;
@@ -1308,13 +1424,13 @@ void TeXOnePar(Buffer const & buf,
 		}
 	}
 
-	// If this is the last paragraph, and a local_font was set upon entering
-	// the inset, and we're using "auto" or "default" encoding, and not
-	// compiling with XeTeX or LuaTeX, the encoding
-	// should be set back to that local_font's encoding.
-	if (runparams.isLastPar && runparams_in.local_font != 0
+	// Information about local language is stored as a font feature.
+	// If this is the last paragraph of the inset and a local_font was set upon entering
+	// and we are mixing encodings ("auto-legacy" or "auto-legacy-plain" and no XeTeX or LuaTeX),
+	// ensure the encoding is set back to the default encoding of the local language.
+	if (runparams.isLastPar && runparams_in.local_font != nullptr
 	    && runparams_in.encoding != runparams_in.local_font->language()->encoding()
-	    && (bparams.inputenc == "auto" || bparams.inputenc == "default")
+	    && (bparams.inputenc == "auto-legacy" || bparams.inputenc == "auto-legacy-plain")
 		&& !runparams.isFullUnicode()
 	   ) {
 		runparams_in.encoding = runparams_in.local_font->language()->encoding();
@@ -1324,14 +1440,18 @@ void TeXOnePar(Buffer const & buf,
 	else
 		runparams_in.encoding = runparams.encoding;
 
+	// Also pass the post_macros upstream
+	runparams_in.post_macro = runparams.post_macro;
+
 
 	// we don't need a newline for the last paragraph!!!
 	// Note from JMarc: we will re-add a \n explicitly in
 	// TeXEnvironment, because it is needed in this case
 	if (nextpar && !os.afterParbreak() && !last_was_separator) {
-		// Make sure to start a new line
-		os << breakln;
 		Layout const & next_layout = nextpar->layout();
+		if (!text.inset().getLayout().parbreakIgnored() && !merged_par)
+			// Make sure to start a new line
+			os << breakln;
 		// A newline '\n' is always output before a command,
 		// so avoid doubling it.
 		if (!next_layout.isCommand()) {
@@ -1355,28 +1475,36 @@ void TeXOnePar(Buffer const & buf,
 			if ((style == next_layout
 			     && !style.parbreak_is_newline
 			     && !text.inset().getLayout().parbreakIsNewline()
+			     && !text.inset().getLayout().parbreakIgnored()
 			     && style.latextype != LATEX_ITEM_ENVIRONMENT
 			     && style.latextype != LATEX_LIST_ENVIRONMENT
-			     && style.align == par.getAlign()
+			     && style.align == par.getAlign(bparams)
 			     && nextpar->getDepth() == par.getDepth()
-			     && nextpar->getAlign() == par.getAlign())
+			     && nextpar->getAlign(bparams) == par.getAlign(bparams))
 			    || (!next_layout.isEnvironment()
 				&& nextpar->getDepth() > par.getDepth()
-				&& nextpar->getAlign() == par.getAlign())
+				&& nextpar->getAlign(bparams) == next_layout.align)
 			    || (!style.isEnvironment()
 				&& next_layout.latextype == LATEX_ENVIRONMENT
 				&& nextpar->getDepth() < par.getDepth())
 			    || (style.isCommand()
 				&& !next_layout.isEnvironment()
-				&& style.align == par.getAlign()
-				&& next_layout.align == nextpar->getAlign())
-			    || (style.align != par.getAlign()
+				&& style.align == par.getAlign(bparams)
+				&& next_layout.align == nextpar->getAlign(bparams))
+			    || (style.align != par.getAlign(bparams)
 				&& tclass.isDefaultLayout(next_layout))) {
-				os << '\n';
+				// and omit paragraph break if it has been deleted with ct
+				// and changes are not shown in output
+				if (!merged_par)
+					os << '\n';
 			}
 		}
 	}
 
+	// Reset language nesting level after intitle command
+	if (intitle_command)
+		state->nest_level_ -= 1;
+
 	LYXERR(Debug::LATEX, "TeXOnePar for paragraph " << pit << " done; ptr "
 		<< &par << " next " << nextpar);
 
@@ -1404,7 +1532,8 @@ void latexParagraphs(Buffer const & buf,
 
 	if (multibib_child && mparams.useBiblatex())
 		os << "\\newrefsection";
-	else if (multibib_child && mparams.useBibtopic()) {
+	else if (multibib_child && mparams.useBibtopic()
+		 && !buf.masterBibInfo().empty()) {
 		os << "\\begin{btUnit}\n";
 		runparams.openbtUnit = true;
 	}
@@ -1420,7 +1549,8 @@ void latexParagraphs(Buffer const & buf,
 				&& runparams.use_CJK))
 	   ) {
 		docstring const cjkenc = bparams.encoding().iconvName() == "UTF-8"
-		  		  			   	 ? from_ascii("UTF8") : from_ascii(bparams.encoding().latexName());
+								 ? from_ascii("UTF8")
+								 : from_ascii(bparams.encoding().latexName());
 		os << "\\begin{CJK}{" << cjkenc
 		   << "}{" << from_ascii(bparams.fonts_cjk) << "}%\n";
 		state->open_encoding_ = CJK;
@@ -1514,7 +1644,8 @@ void latexParagraphs(Buffer const & buf,
 		    && layout.latexname() == bparams.multibib) {
 			if (runparams.openbtUnit)
 				os << "\\end{btUnit}\n";
-			if (!bparams.useBiblatex()) {
+			if (!bparams.useBiblatex()
+			    && !buf.masterBibInfo().empty()) {
 				os << '\n' << "\\begin{btUnit}\n";
 				runparams.openbtUnit = true;
 			}
@@ -1526,6 +1657,22 @@ void latexParagraphs(Buffer const & buf,
 			continue;
 		}
 
+		// Do not output empty environments if the whole paragraph has
+		// been deleted with ct and changes are not output.
+		if (size_t(pit + 1) < paragraphs.size()) {
+			ParagraphList::const_iterator nextpar = paragraphs.constIterator(pit + 1);
+			Paragraph const & cpar = paragraphs.at(pit);
+			if ((par->layout() != nextpar->layout()
+			     || par->params().depth() == nextpar->params().depth()
+			     || par->params().leftIndent() == nextpar->params().leftIndent())
+			    && !runparams.for_search && cpar.size() > 0
+			    && cpar.isDeleted(0, cpar.size()) && !bparams.output_changes) {
+				if (!bparams.output_changes && !cpar.parEndChange().deleted())
+					os << '\n' << '\n';
+				continue;
+			}
+		}
+
 		TeXEnvironmentData const data =
 			prepareEnvironment(buf, text, par, os, runparams);
 		// pit can be changed in TeXEnvironment.
@@ -1533,6 +1680,7 @@ void latexParagraphs(Buffer const & buf,
 		finishEnvironment(os, runparams, data);
 	}
 
+	// FIXME: uncomment the content or remove this block
 	if (pit == runparams.par_end) {
 			// Make sure that the last paragraph is
 			// correctly terminated (because TeXOnePar does
@@ -1540,8 +1688,11 @@ void latexParagraphs(Buffer const & buf,
 			//os << '\n';
 	}
 
-	// It might be that we only have a title in this document
-	if (was_title && !already_title) {
+	// It might be that we only have a title in this document.
+	// But if we're in a branch, this is not the end of
+	// the document. (There may be some other checks of this
+	// kind that are needed.)
+	if (was_title && !already_title && !runparams.inbranch) {
 		if (tclass.titletype() == TITLE_ENVIRONMENT) {
 			os << "\\end{" << from_ascii(tclass.titlename())
 			   << "}\n";
@@ -1556,13 +1707,17 @@ void latexParagraphs(Buffer const & buf,
 
 	// if "auto end" is switched off, explicitly close the language at the end
 	// but only if the last par is in a babel or polyglossia language
+	Language const * const lastpar_language =
+			paragraphs.at(lastpit).getParLanguage(bparams);
 	if (maintext && !lyxrc.language_auto_end && !mainlang.empty() &&
-		paragraphs.at(lastpit).getParLanguage(bparams)->encoding()->package() != Encoding::CJK) {
+		lastpar_language->encoding()->package() != Encoding::CJK) {
 		os << from_utf8(subst(lang_end_command,
 					"$$lang",
 					mainlang))
 			<< '\n';
-		if (using_begin_end)
+		// If we have language_auto_begin, the stack will
+		// already be empty, nothing to pop()
+		if (using_begin_end && !lyxrc.language_auto_begin)
 			popLanguageName();
 	}
 
@@ -1573,14 +1728,29 @@ void latexParagraphs(Buffer const & buf,
 		state->open_encoding_ = none;
 	}
 	// Likewise for polyglossia or when using begin/end commands
+	// or at the very end of an active branch inset with a language switch
+	Language const * const outer_language = (runparams.local_font != nullptr)
+			? runparams.local_font->language() : bparams.language;
+	string const & prev_lang = runparams.use_polyglossia
+			? getPolyglossiaEnvName(outer_language)
+			: outer_language->babel();
+	string const lastpar_lang = runparams.use_polyglossia ?
+		getPolyglossiaEnvName(lastpar_language): lastpar_language->babel();
 	string const & cur_lang = openLanguageName(state);
-	if (maintext && !is_child && !cur_lang.empty()) {
+	if (((runparams.inbranch && langOpenedAtThisLevel(state) && prev_lang != cur_lang)
+	     || (maintext && !is_child)) && !cur_lang.empty()) {
 		os << from_utf8(subst(lang_end_command,
 					"$$lang",
 					cur_lang))
 		   << '\n';
 		if (using_begin_end)
 			popLanguageName();
+	} else if (runparams.inbranch && !using_begin_end
+		   && prev_lang != lastpar_lang && !lastpar_lang.empty()) {
+		// with !using_begin_end, cur_lang is empty, so we need to
+		// compare against the paragraph language (and we are in the
+		// last paragraph at this point)
+		os << subst(lang_begin_command, "$$lang", prev_lang) << '\n';
 	}
 
 	// reset inherited encoding
@@ -1596,44 +1766,44 @@ void latexParagraphs(Buffer const & buf,
 	}
 }
 
-
+// Switch the input encoding for some part(s) of the document.
 pair<bool, int> switchEncoding(odocstream & os, BufferParams const & bparams,
 		   OutputParams const & runparams, Encoding const & newEnc,
 		   bool force, bool noswitchmacro)
 {
-	// XeTeX/LuaTeX use only one encoding per document:
-	// * with useNonTeXFonts: "utf8plain",
-	// * with XeTeX and TeX fonts: "ascii" (inputenc fails),
-	// * with LuaTeX and TeX fonts: only one encoding accepted by luainputenc.
+	// Never switch encoding with XeTeX/LuaTeX
+	// or if we're in a moving argument or inherit the outer encoding.
 	if (runparams.isFullUnicode() || newEnc.name() == "inherit")
+		return make_pair(false, 0);	
+
+	// Only switch for auto-selected legacy encodings (inputenc setting
+	// "auto-legacy" or "auto-legacy-plain").
+	// The "listings" environment can force a switch also with other
+	// encoding settings (it does not support variable width encodings
+	// (utf8, jis, ...) under 8-bit latex engines).
+	if (!force && ((bparams.inputenc != "auto-legacy" && bparams.inputenc != "auto-legacy-plain")
+				   || runparams.moving_arg))
 		return make_pair(false, 0);
 
 	Encoding const & oldEnc = *runparams.encoding;
-	bool moving_arg = runparams.moving_arg;
-	if (!force
-	    && ((bparams.inputenc != "auto" && bparams.inputenc != "default") || moving_arg))
-		return make_pair(false, 0);
-
-	// Do nothing if the encoding is unchanged.
-	if (oldEnc.name() == newEnc.name())
+	// Do not switch, if the encoding is unchanged or switching is not supported.
+	if (oldEnc.name() == newEnc.name()
+		|| oldEnc.package() == Encoding::japanese
+		|| oldEnc.package() == Encoding::none
+		|| newEnc.package() == Encoding::none
+		|| runparams.for_search)
 		return make_pair(false, 0);
-
 	// FIXME We ignore encoding switches from/to encodings that do
 	// neither support the inputenc package nor the CJK package here.
-	// This does of course only work in special cases (e.g. switch from
-	// tis620-0 to latin1, but the text in latin1 contains ASCII only),
-	// but it is the best we can do
-	//
-	// 2019-01-08 Possibly no longer required since tis620-0 is supported
-	// by inputenc (but check special encodings "utf8-plain" and "default").
-	if (oldEnc.package() == Encoding::none || newEnc.package() == Encoding::none)
-		return make_pair(false, 0);
+	// This may fail for characters not supported by "unicodesymbols"
+	// or for non-ASCII characters in "listings"
+	// but it is the best we can do.
 
 	// change encoding
 	LYXERR(Debug::LATEX, "Changing LaTeX encoding from "
 		   << oldEnc.name() << " to " << newEnc.name());
 	os << setEncoding(newEnc.iconvName());
-	if (bparams.inputenc == "default")
+	if (bparams.inputenc == "auto-legacy-plain")
 	  return make_pair(true, 0);
 
 	docstring const inputenc_arg(from_ascii(newEnc.latexName()));
@@ -1641,7 +1811,7 @@ pair<bool, int> switchEncoding(odocstream & os, BufferParams const & bparams,
 	switch (newEnc.package()) {
 		case Encoding::none:
 		case Encoding::japanese:
-			// shouldn't ever reach here, see above
+			// shouldn't ever reach here (see above) but avoids warning.
 			return make_pair(true, 0);
 		case Encoding::inputenc: {
 			int count = inputenc_arg.length();
@@ -1657,7 +1827,7 @@ pair<bool, int> switchEncoding(odocstream & os, BufferParams const & bparams,
 				state->open_encoding_ = none;
 				count += 7;
 			}
-			if (runparams.local_font != 0
+			if (runparams.local_font != nullptr
 			    && 	oldEnc.package() == Encoding::CJK) {
 				// within insets, \inputenc switches need
 				// to be embraced within \bgroup...\egroup;
@@ -1666,8 +1836,7 @@ pair<bool, int> switchEncoding(odocstream & os, BufferParams const & bparams,
 				count += 7;
 				state->open_encoding_ = inputenc;
 			}
-			// with the japanese option, inputenc is omitted.
-			if (runparams.use_japanese || noswitchmacro)
+			if (noswitchmacro)
 				return make_pair(true, count);
 			os << "\\inputencoding{" << inputenc_arg << '}';
 			return make_pair(true, count + 16);