src/output_latex.cpp

   1 /**
   2  * \file output_latex.cpp
   3  * This file is part of LyX, the document processor.
   4  * Licence details can be found in the file COPYING.
   5  *
   6  * \author Lars Gullik Bjønnes
   7  *
   8  * Full author contact details are available in file CREDITS.
   9  */
  10
  11 #include <config.h>
  12
  13 #include "output_latex.h"
  14
  15 #include "BiblioInfo.h"
  16 #include "Buffer.h"
  17 #include "BufferParams.h"
  18 #include "Encoding.h"
  19 #include "Font.h"
  20 #include "InsetList.h"
  21 #include "Language.h"
  22 #include "LaTeXFeatures.h"
  23 #include "Layout.h"
  24 #include "LyXRC.h"
  25 #include "OutputParams.h"
  26 #include "Paragraph.h"
  27 #include "ParagraphParameters.h"
  28 #include "texstream.h"
  29 #include "TextClass.h"
  30
  31 #include "insets/InsetBibitem.h"
  32 #include "insets/InsetArgument.h"
  33
  34 #include "frontends/alert.h"
  35
  36 #include "support/lassert.h"
  37 #include "support/convert.h"
  38 #include "support/debug.h"
  39 #include "support/lstrings.h"
  40 #include "support/lyxalgo.h"
  41 #include "support/textutils.h"
  42 #include "support/gettext.h"
  43
  44 #include <QThreadStorage>
  45
  46 #include <list>
  47 #include <stack>
  48
  49 using namespace std;
  50 using namespace lyx::support;
  51
  52
  53 namespace lyx {
  54
  55 namespace {
  56
  57 enum OpenEncoding {
  58         none,
  59         inputenc,
  60         CJK
  61 };
  62
  63
  64 struct OutputState
  65 {
  66         OutputState() : open_encoding_(none), cjk_inherited_(0),
  67                 prev_env_language_(nullptr), nest_level_(0)
  68         {
  69         }
  70         OpenEncoding open_encoding_;
  71         int cjk_inherited_;
  72         Language const * prev_env_language_;
  73         int nest_level_;
  74         stack<int> lang_switch_depth_;          // Both are always empty when
  75         stack<string> open_polyglossia_lang_;   // not using polyglossia
  76 };
  77
  78
  79 OutputState * getOutputState()
  80 {
  81         // FIXME An instance of OutputState should be kept around for each export
  82         //       instead of using local thread storage
  83         static QThreadStorage<OutputState *> outputstate;
  84         if (!outputstate.hasLocalData())
  85                 outputstate.setLocalData(new OutputState);
  86         return outputstate.localData();
  87 }
  88
  89
  90 string const & openLanguageName(OutputState const * state)
  91 {
  92         // Return a reference to the last active language opened with
  93         // polyglossia or when using begin/end commands. If none or when
  94         // using babel with only a begin command, return a reference to
  95         // an empty string.
  96
  97         static string const empty;
  98
  99         return state->open_polyglossia_lang_.empty()
 100                 ? empty
 101                 : state->open_polyglossia_lang_.top();
 102 }
 103
 104
 105 bool atSameLastLangSwitchDepth(OutputState const * state)
 106 {
 107         // Return true if the actual nest level is the same at which the
 108         // language was switched when using polyglossia or begin/end
 109         // commands. Instead, return always true when using babel with
 110         // only a begin command.
 111
 112         return state->lang_switch_depth_.size() == 0
 113                         ? true
 114                         : abs(state->lang_switch_depth_.top()) == state->nest_level_;
 115 }
 116
 117
 118 bool isLocalSwitch(OutputState const * state)
 119 {
 120         // Return true if the language was opened by a local command switch.
 121
 122         return state->lang_switch_depth_.size()
 123                 && state->lang_switch_depth_.top() < 0;
 124 }
 125
 126
 127 bool langOpenedAtThisLevel(OutputState const * state)
 128 {
 129         // Return true if the language was opened at the current nesting level.
 130
 131         return state->lang_switch_depth_.size()
 132                 && abs(state->lang_switch_depth_.top()) == state->nest_level_;
 133 }
 134
 135
 136 string const getPolyglossiaEnvName(Language const * lang)
 137 {
 138         string result = lang->polyglossia();
 139         if (result == "arabic")
 140                 // exceptional spelling; see polyglossia docs.
 141                 result = "Arabic";
 142         return result;
 143 }
 144
 145
 146 string const getPolyglossiaBegin(string const & lang_begin_command,
 147                                  string const & lang, string const & opts,
 148                                  bool const localswitch = false)
 149 {
 150         string result;
 151         if (!lang.empty()) {
 152                 // we need to revert the upcasing done in getPolyglossiaEnvName()
 153                 // in case we have a local polyglossia command (\textarabic).
 154                 string language = localswitch ? ascii_lowercase(lang) : lang;
 155                 result = subst(lang_begin_command, "$$lang", language);
 156         }
 157         string options = opts.empty() ?
 158                     string() : "[" + opts + "]";
 159         result = subst(result, "$$opts", options);
 160
 161         return result;
 162 }
 163
 164
 165 struct TeXEnvironmentData
 166 {
 167         bool cjk_nested;
 168         Layout const * style;
 169         Language const * par_language;
 170         Encoding const * prev_encoding;
 171         bool leftindent_open;
 172 };
 173
 174
 175 static TeXEnvironmentData prepareEnvironment(Buffer const & buf,
 176                                         Text const & text,
 177                                         ParagraphList::const_iterator pit,
 178                                         otexstream & os,
 179                                         OutputParams const & runparams)
 180 {
 181         TeXEnvironmentData data;
 182
 183         BufferParams const & bparams = buf.params();
 184
 185         // FIXME This test should not be necessary.
 186         // We should perhaps issue an error if it is.
 187         Layout const & style = text.inset().forcePlainLayout() ?
 188                 bparams.documentClass().plainLayout() : pit->layout();
 189
 190         ParagraphList const & paragraphs = text.paragraphs();
 191         ParagraphList::const_iterator const priorpit =
 192                 pit == paragraphs.begin() ? pit : prev(pit, 1);
 193
 194         OutputState * state = getOutputState();
 195         bool const use_prev_env_language = state->prev_env_language_ != nullptr
 196                         && priorpit->layout().isEnvironment()
 197                         && (priorpit->getDepth() > pit->getDepth()
 198                             || (priorpit->getDepth() == pit->getDepth()
 199                                 && priorpit->layout() != pit->layout()));
 200
 201         data.prev_encoding = runparams.encoding;
 202         data.par_language = pit->getParLanguage(bparams);
 203         Language const * const doc_language = bparams.language;
 204         Language const * const prev_par_language =
 205                 (pit != paragraphs.begin())
 206                 ? (use_prev_env_language ? state->prev_env_language_
 207                                          : priorpit->getParLanguage(bparams))
 208                 : doc_language;
 209
 210         bool const use_polyglossia = runparams.use_polyglossia;
 211         string const par_lang = use_polyglossia ?
 212                 getPolyglossiaEnvName(data.par_language) : data.par_language->babel();
 213         string const prev_par_lang = use_polyglossia ?
 214                 getPolyglossiaEnvName(prev_par_language) : prev_par_language->babel();
 215         string const doc_lang = use_polyglossia ?
 216                 getPolyglossiaEnvName(doc_language) : doc_language->babel();
 217         string const lang_begin_command = use_polyglossia ?
 218                 "\\begin{$$lang}" : lyxrc.language_command_begin;
 219         string const lang_end_command = use_polyglossia ?
 220                 "\\end{$$lang}" : lyxrc.language_command_end;
 221         bool const using_begin_end = use_polyglossia ||
 222                                         !lang_end_command.empty();
 223
 224         // For polyglossia, switch language outside of environment, if possible.
 225         if (par_lang != prev_par_lang) {
 226                 if ((!using_begin_end || langOpenedAtThisLevel(state)) &&
 227                     !lang_end_command.empty() &&
 228                     prev_par_lang != doc_lang &&
 229                     !prev_par_lang.empty()) {
 230                         os << from_ascii(subst(
 231                                 lang_end_command,
 232                                 "$$lang",
 233                                 prev_par_lang))
 234                           // the '%' is necessary to prevent unwanted whitespace
 235                           << "%\n";
 236                         if (using_begin_end)
 237                                 popLanguageName();
 238                 }
 239
 240                 // If no language was explicitly opened and we are using
 241                 // polyglossia or begin/end commands, then the current
 242                 // language is the document language.
 243                 string const & cur_lang = using_begin_end
 244                                           && state->lang_switch_depth_.size()
 245                                                   ? openLanguageName(state)
 246                                                   : doc_lang;
 247
 248                 if ((lang_end_command.empty() ||
 249                     par_lang != doc_lang ||
 250                     par_lang != cur_lang) &&
 251                     !par_lang.empty()) {
 252                             string bc = use_polyglossia ?
 253                                         getPolyglossiaBegin(lang_begin_command, par_lang,
 254                                                             data.par_language->polyglossiaOpts())
 255                                       : subst(lang_begin_command, "$$lang", par_lang);
 256                             os << bc;
 257                             // the '%' is necessary to prevent unwanted whitespace
 258                             os << "%\n";
 259                             if (using_begin_end)
 260                                     pushLanguageName(par_lang);
 261                 }
 262         }
 263
 264         data.leftindent_open = false;
 265         if (!pit->params().leftIndent().zero()) {
 266                 os << "\\begin{LyXParagraphLeftIndent}{"
 267                    << from_ascii(pit->params().leftIndent().asLatexString())
 268                    << "}\n";
 269                 data.leftindent_open = true;
 270         }
 271
 272         if (style.isEnvironment())
 273                 state->nest_level_ += 1;
 274
 275         if (style.isEnvironment() && !style.latexname().empty()) {
 276                 os << "\\begin{" << from_ascii(style.latexname()) << '}';
 277                 if (!style.latexargs().empty()) {
 278                         OutputParams rp = runparams;
 279                         rp.local_font = &pit->getFirstFontSettings(bparams);
 280                         latexArgInsets(paragraphs, pit, os, rp, style.latexargs());
 281                 }
 282                 if (style.latextype == LATEX_LIST_ENVIRONMENT) {
 283                         os << '{'
 284                            << pit->params().labelWidthString()
 285                            << "}\n";
 286                 } else if (style.labeltype == LABEL_BIBLIO) {
 287                         if (pit->params().labelWidthString().empty())
 288                                 os << '{' << bibitemWidest(buf, runparams) << "}\n";
 289                         else
 290                                 os << '{'
 291                                   << pit->params().labelWidthString()
 292                                   << "}\n";
 293                 } else
 294                         os << from_ascii(style.latexparam()) << '\n';
 295                 if (style.latextype == LATEX_BIB_ENVIRONMENT
 296                     || style.latextype == LATEX_ITEM_ENVIRONMENT
 297                     || style.latextype ==  LATEX_LIST_ENVIRONMENT) {
 298                         OutputParams rp = runparams;
 299                         rp.local_font = &pit->getFirstFontSettings(bparams);
 300                         latexArgInsets(paragraphs, pit, os, rp, style.listpreamble(),
 301                                        "listpreamble:");
 302                 }
 303         }
 304         data.style = &style;
 305
 306         // in multilingual environments, the CJK tags have to be nested properly
 307         data.cjk_nested = false;
 308         if (!bparams.useNonTeXFonts
 309             && (bparams.inputenc == "auto-legacy"
 310                         || bparams.inputenc == "auto-legacy-plain")
 311             && data.par_language->encoding()->package() == Encoding::CJK
 312             && state->open_encoding_ != CJK && pit->isMultiLingual(bparams)) {
 313                 if (prev_par_language->encoding()->package() == Encoding::CJK) {
 314                         os << "\\begin{CJK}{"
 315                            << from_ascii(data.par_language->encoding()->latexName())
 316                            << "}{" << from_ascii(bparams.fonts_cjk) << "}%\n";
 317                 }
 318                 state->open_encoding_ = CJK;
 319                 data.cjk_nested = true;
 320         }
 321         return data;
 322 }
 323
 324
 325 static void finishEnvironment(otexstream & os, OutputParams const & runparams,
 326                               TeXEnvironmentData const & data)
 327 {
 328         OutputState * state = getOutputState();
 329         // BufferParams const & bparams = buf.params(); // FIXME: for speedup shortcut below, would require passing of "buf" as argument
 330         if (state->open_encoding_ == CJK && data.cjk_nested) {
 331                 // We need to close the encoding even if it does not change
 332                 // to do correct environment nesting
 333                 os << "\\end{CJK}\n";
 334                 state->open_encoding_ = none;
 335         }
 336
 337         if (data.style->isEnvironment()) {
 338                 os << breakln;
 339                 bool const using_begin_end =
 340                         runparams.use_polyglossia ||
 341                                 !lyxrc.language_command_end.empty();
 342                 // Close any language opened at this nest level
 343                 if (using_begin_end) {
 344                         while (langOpenedAtThisLevel(state)) {
 345                                 if (isLocalSwitch(state)) {
 346                                         os << "}";
 347                                 } else {
 348                                         os << "\\end{"
 349                                            << openLanguageName(state)
 350                                            << "}%\n";
 351                                 }
 352                                 popLanguageName();
 353                         }
 354                 }
 355                 state->nest_level_ -= 1;
 356                 string const & name = data.style->latexname();
 357                 if (!name.empty())
 358                         os << "\\end{" << from_ascii(name) << "}\n";
 359                 state->prev_env_language_ = data.par_language;
 360                 if (runparams.encoding != data.prev_encoding) {
 361                         runparams.encoding = data.prev_encoding;
 362                         os << setEncoding(data.prev_encoding->iconvName());
 363                 }
 364         }
 365
 366         if (data.leftindent_open) {
 367                 os << breakln << "\\end{LyXParagraphLeftIndent}\n";
 368                 state->prev_env_language_ = data.par_language;
 369                 if (runparams.encoding != data.prev_encoding) {
 370                         runparams.encoding = data.prev_encoding;
 371                         os << setEncoding(data.prev_encoding->iconvName());
 372                 }
 373         }
 374
 375         // Check whether we should output a blank line after the environment
 376         if (!data.style->nextnoindent)
 377                 os << '\n';
 378 }
 379
 380
 381 void TeXEnvironment(Buffer const & buf, Text const & text,
 382                     OutputParams const & runparams,
 383                     pit_type & pit, otexstream & os)
 384 {
 385         ParagraphList const & paragraphs = text.paragraphs();
 386         ParagraphList::const_iterator ipar = paragraphs.constIterator(pit);
 387         LYXERR(Debug::LATEX, "TeXEnvironment for paragraph " << pit);
 388
 389         Layout const & current_layout = ipar->layout();
 390         depth_type const current_depth = ipar->params().depth();
 391         Length const & current_left_indent = ipar->params().leftIndent();
 392
 393         // This is for debugging purpose at the end.
 394         pit_type const par_begin = pit;
 395         for (; pit < runparams.par_end; ++pit) {
 396                 ParagraphList::const_iterator par = paragraphs.constIterator(pit);
 397
 398                 // check first if this is an higher depth paragraph.
 399                 bool go_out = (par->params().depth() < current_depth);
 400                 if (par->params().depth() == current_depth) {
 401                         // This environment is finished.
 402                         go_out |= (par->layout() != current_layout);
 403                         go_out |= (par->params().leftIndent() != current_left_indent);
 404                 }
 405                 if (go_out) {
 406                         // nothing to do here, restore pit and go out.
 407                         pit--;
 408                         break;
 409                 }
 410
 411                 if (par->layout() == current_layout
 412                         && par->params().depth() == current_depth
 413                         && par->params().leftIndent() == current_left_indent) {
 414                         // We are still in the same environment so TeXOnePar and continue;
 415                         TeXOnePar(buf, text, pit, os, runparams);
 416                         continue;
 417                 }
 418
 419                 // We are now in a deeper environment.
 420                 // Either par->layout() != current_layout
 421                 // Or     par->params().depth() > current_depth
 422                 // Or     par->params().leftIndent() != current_left_indent)
 423
 424                 // FIXME This test should not be necessary.
 425                 // We should perhaps issue an error if it is.
 426                 bool const force_plain_layout = text.inset().forcePlainLayout();
 427                 Layout const & style = force_plain_layout
 428                         ? buf.params().documentClass().plainLayout()
 429                         : par->layout();
 430
 431                 if (!style.isEnvironment()) {
 432                         // This is a standard paragraph, no need to call TeXEnvironment.
 433                         TeXOnePar(buf, text, pit, os, runparams);
 434                         continue;
 435                 }
 436
 437                 // Do not output empty environments if the whole paragraph has
 438                 // been deleted with ct and changes are not output.
 439                 if (size_t(pit + 1) < paragraphs.size()) {
 440                         ParagraphList::const_iterator nextpar = paragraphs.constIterator(pit + 1);
 441                         Paragraph const & cpar = paragraphs.at(pit);
 442                         if ((par->layout() != nextpar->layout()
 443                              || par->params().depth() == nextpar->params().depth()
 444                              || par->params().leftIndent() == nextpar->params().leftIndent())
 445                             && !runparams.for_search && cpar.size() > 0
 446                             && cpar.isDeleted(0, cpar.size()) && !buf.params().output_changes) {
 447                                 if (!buf.params().output_changes && !cpar.parEndChange().deleted())
 448                                         os << '\n' << '\n';
 449                                 continue;
 450                         }
 451                 }
 452
 453                 // This is a new environment.
 454                 TeXEnvironmentData const data =
 455                         prepareEnvironment(buf, text, par, os, runparams);
 456                 // Recursive call to TeXEnvironment!
 457                 TeXEnvironment(buf, text, runparams, pit, os);
 458                 finishEnvironment(os, runparams, data);
 459         }
 460
 461         if (pit != runparams.par_end)
 462                 LYXERR(Debug::LATEX, "TeXEnvironment for paragraph " << par_begin << " done.");
 463 }
 464
 465
 466 void getArgInsets(otexstream & os, OutputParams const & runparams, Layout::LaTeXArgMap const & latexargs,
 467                   map<int, lyx::InsetArgument const *> ilist, vector<string> required, string const & prefix)
 468 {
 469         unsigned int const argnr = latexargs.size();
 470         if (argnr == 0)
 471                 return;
 472
 473         // Default and preset args are always output, so if they require
 474         // other arguments, consider this.
 475         for (auto const & larg : latexargs) {
 476                 Layout::latexarg const & arg = larg.second;
 477                 if ((!arg.presetarg.empty() || !arg.defaultarg.empty()) && !arg.requires.empty()) {
 478                                 vector<string> req = getVectorFromString(arg.requires);
 479                                 required.insert(required.end(), req.begin(), req.end());
 480                         }
 481         }
 482
 483         for (unsigned int i = 1; i <= argnr; ++i) {
 484                 map<int, InsetArgument const *>::const_iterator lit = ilist.find(i);
 485                 bool inserted = false;
 486                 if (lit != ilist.end()) {
 487                         InsetArgument const * ins = (*lit).second;
 488                         if (ins) {
 489                                 Layout::LaTeXArgMap::const_iterator const lait =
 490                                                 latexargs.find(ins->name());
 491                                 if (lait != latexargs.end()) {
 492                                         Layout::latexarg arg = (*lait).second;
 493                                         docstring ldelim;
 494                                         docstring rdelim;
 495                                         if (!arg.nodelims) {
 496                                                 ldelim = arg.mandatory ?
 497                                                         from_ascii("{") : from_ascii("[");
 498                                                 rdelim = arg.mandatory ?
 499                                                         from_ascii("}") : from_ascii("]");
 500                                         }
 501                                         if (!arg.ldelim.empty())
 502                                                 ldelim = arg.ldelim;
 503                                         if (!arg.rdelim.empty())
 504                                                 rdelim = arg.rdelim;
 505                                         ins->latexArgument(os, runparams, ldelim, rdelim, arg.presetarg);
 506                                         if (prefix == "listpreamble:")
 507                                                 os << breakln;
 508                                         inserted = true;
 509                                 }
 510                         }
 511                 }
 512                 if (!inserted) {
 513                         Layout::LaTeXArgMap::const_iterator lait = latexargs.begin();
 514                         Layout::LaTeXArgMap::const_iterator const laend = latexargs.end();
 515                         for (; lait != laend; ++lait) {
 516                                 string const name = prefix + convert<string>(i);
 517                                 if ((*lait).first == name) {
 518                                         Layout::latexarg arg = (*lait).second;
 519                                         docstring preset = arg.presetarg;
 520                                         if (!arg.defaultarg.empty()) {
 521                                                 if (!preset.empty())
 522                                                         preset += ",";
 523                                                 preset += arg.defaultarg;
 524                                         }
 525                                         if (arg.mandatory) {
 526                                                 docstring ldelim = arg.ldelim.empty() ?
 527                                                                 from_ascii("{") : arg.ldelim;
 528                                                 docstring rdelim = arg.rdelim.empty() ?
 529                                                                 from_ascii("}") : arg.rdelim;
 530                                                 os << ldelim << preset << rdelim;
 531                                         } else if (!preset.empty()) {
 532                                                 docstring ldelim = arg.ldelim.empty() ?
 533                                                                 from_ascii("[") : arg.ldelim;
 534                                                 docstring rdelim = arg.rdelim.empty() ?
 535                                                                 from_ascii("]") : arg.rdelim;
 536                                                 os << ldelim << preset << rdelim;
 537                                         } else if (find(required.begin(), required.end(),
 538                                                    (*lait).first) != required.end()) {
 539                                                 docstring ldelim = arg.ldelim.empty() ?
 540                                                                 from_ascii("[") : arg.ldelim;
 541                                                 docstring rdelim = arg.rdelim.empty() ?
 542                                                                 from_ascii("]") : arg.rdelim;
 543                                                 os << ldelim << rdelim;
 544                                         } else
 545                                                 break;
 546                                 }
 547                         }
 548                 }
 549         }
 550         if (runparams.for_search) {
 551                 // Mark end of arguments for findadv() only
 552                 os << "\\endarguments{}";
 553         }
 554 }
 555
 556
 557 } // namespace
 558
 559
 560 void pushLanguageName(string const & lang_name, bool localswitch)
 561 {
 562         OutputState * state = getOutputState();
 563
 564         int nest_level = localswitch ? -state->nest_level_ : state->nest_level_;
 565         state->lang_switch_depth_.push(nest_level);
 566         state->open_polyglossia_lang_.push(lang_name);
 567 }
 568
 569
 570 void popLanguageName()
 571 {
 572         OutputState * state = getOutputState();
 573
 574         state->lang_switch_depth_.pop();
 575         state->open_polyglossia_lang_.pop();
 576 }
 577
 578
 579 string const & openLanguageName()
 580 {
 581         OutputState * state = getOutputState();
 582
 583         return openLanguageName(state);
 584 }
 585
 586
 587 namespace {
 588
 589 void addArgInsets(Paragraph const & par, string const & prefix,
 590                  Layout::LaTeXArgMap const & latexargs,
 591                  map<int, InsetArgument const *> & ilist,
 592                  vector<string> & required)
 593 {
 594         for (auto const & table : par.insetList()) {
 595                 InsetArgument const * arg = table.inset->asInsetArgument();
 596                 if (!arg)
 597                         continue;
 598                 if (arg->name().empty()) {
 599                         LYXERR0("Error: Unnamed argument inset!");
 600                         continue;
 601                 }
 602                 string const name = prefix.empty() ?
 603                         arg->name() : split(arg->name(), ':');
 604                 // why converting into an integer?
 605                 unsigned int const nr = convert<unsigned int>(name);
 606                 if (ilist.find(nr) == ilist.end())
 607                         ilist[nr] = arg;
 608                 Layout::LaTeXArgMap::const_iterator const lit =
 609                         latexargs.find(arg->name());
 610                 if (lit != latexargs.end()) {
 611                         Layout::latexarg const & larg = lit->second;
 612                         vector<string> req = getVectorFromString(larg.requires);
 613                         move(req.begin(), req.end(), back_inserter(required));
 614                 }
 615         }
 616 }
 617
 618 } // namespace
 619
 620
 621 void latexArgInsets(Paragraph const & par, otexstream & os,
 622                     OutputParams const & runparams,
 623                     Layout::LaTeXArgMap const & latexargs,
 624                     string const & prefix)
 625 {
 626         map<int, InsetArgument const *> ilist;
 627         vector<string> required;
 628         addArgInsets(par, prefix, latexargs, ilist, required);
 629         getArgInsets(os, runparams, latexargs, ilist, required, prefix);
 630 }
 631
 632
 633 void latexArgInsets(ParagraphList const & pars,
 634                     ParagraphList::const_iterator pit,
 635                     otexstream & os, OutputParams const & runparams,
 636                     Layout::LaTeXArgMap const & latexargs,
 637                     string const & prefix)
 638 {
 639         map<int, InsetArgument const *> ilist;
 640         vector<string> required;
 641
 642         depth_type const current_depth = pit->params().depth();
 643         Layout const current_layout = pit->layout();
 644
 645         // get the first paragraph in sequence with this layout and depth
 646         pit_type offset = 0;
 647         while (true) {
 648                 if (lyx::prev(pit, offset) == pars.begin())
 649                         break;
 650                 ParagraphList::const_iterator priorpit = lyx::prev(pit, offset + 1);
 651                 if (priorpit->layout() == current_layout
 652                     && priorpit->params().depth() == current_depth)
 653                         ++offset;
 654                 else
 655                         break;
 656         }
 657
 658         ParagraphList::const_iterator spit = lyx::prev(pit, offset);
 659
 660         for (; spit != pars.end(); ++spit) {
 661                 if (spit->layout() != current_layout ||
 662                     spit->params().depth() < current_depth)
 663                         break;
 664                 if (spit->params().depth() > current_depth)
 665                         continue;
 666                 addArgInsets(*spit, prefix, latexargs, ilist, required);
 667         }
 668         getArgInsets(os, runparams, latexargs, ilist, required, prefix);
 669 }
 670
 671
 672 void latexArgInsetsForParent(ParagraphList const & pars, otexstream & os,
 673                              OutputParams const & runparams,
 674                              Layout::LaTeXArgMap const & latexargs,
 675                              string const & prefix)
 676 {
 677         map<int, InsetArgument const *> ilist;
 678         vector<string> required;
 679
 680         for (Paragraph const & par : pars) {
 681                 if (par.layout().hasArgs())
 682                         // The InsetArguments inside this paragraph refer to this paragraph
 683                         continue;
 684                 addArgInsets(par, prefix, latexargs, ilist, required);
 685         }
 686         getArgInsets(os, runparams, latexargs, ilist, required, prefix);
 687 }
 688
 689
 690 namespace {
 691
 692 // output the proper paragraph start according to latextype.
 693 void parStartCommand(Paragraph const & par, otexstream & os,
 694                      OutputParams const & runparams, Layout const & style)
 695 {
 696         switch (style.latextype) {
 697         case LATEX_COMMAND:
 698                 if (par.needsCProtection(runparams.moving_arg)) {
 699                         if (contains(runparams.active_chars, '^'))
 700                                 // cprotect relies on ^ being on catcode 7
 701                                 os << "\\begingroup\\catcode`\\^=7";
 702                         os << "\\cprotect";
 703                 }
 704                 os << '\\' << from_ascii(style.latexname());
 705
 706                 // Command arguments
 707                 if (!style.latexargs().empty())
 708                         latexArgInsets(par, os, runparams, style.latexargs());
 709                 os << from_ascii(style.latexparam());
 710                 break;
 711         case LATEX_ITEM_ENVIRONMENT:
 712         case LATEX_LIST_ENVIRONMENT:
 713                 if (runparams.for_search) {
 714                         os << "\\" + style.itemcommand() << "{" << style.latexname() << "}";
 715                 }
 716                 else {
 717                         os << "\\" + style.itemcommand();
 718                         // Item arguments
 719                         if (!style.itemargs().empty())
 720                                 latexArgInsets(par, os, runparams, style.itemargs(), "item:");
 721                         os << " ";
 722                 }
 723                 break;
 724         case LATEX_ENVIRONMENT:
 725                 if (runparams.for_search) {
 726                         os << "\\latexenvironment{" << style.latexname() << "}{";
 727                 }
 728                 break;
 729         case LATEX_BIB_ENVIRONMENT:
 730                 // ignore this, the inset will write itself
 731                 break;
 732         default:
 733                 break;
 734         }
 735 }
 736
 737 } // namespace
 738
 739 // FIXME: this should be anonymous
 740 void TeXOnePar(Buffer const & buf,
 741                Text const & text,
 742                pit_type pit,
 743                otexstream & os,
 744                OutputParams const & runparams_in,
 745                string const & everypar,
 746                int start_pos, int end_pos,
 747                bool const force)
 748 {
 749         BufferParams const & bparams = runparams_in.is_child
 750                 ? buf.masterParams() : buf.params();
 751         ParagraphList const & paragraphs = text.paragraphs();
 752         Paragraph const & par = paragraphs.at(pit);
 753         // FIXME This check should not really be needed.
 754         // Perhaps we should issue an error if it is.
 755         Layout const & style = text.inset().forcePlainLayout() ?
 756                 bparams.documentClass().plainLayout() : par.layout();
 757
 758         if (style.inpreamble && !force)
 759                 return;
 760
 761         // Do not output empty commands if the whole paragraph has
 762         // been deleted with ct and changes are not output.
 763         if (!runparams_in.for_search && style.latextype != LATEX_ENVIRONMENT
 764             && par.size() > 0 && par.isDeleted(0, par.size()) && !bparams.output_changes)
 765                 return;
 766
 767         LYXERR(Debug::LATEX, "TeXOnePar for paragraph " << pit << " ptr " << &par << " '"
 768                 << everypar << "'");
 769
 770         OutputParams runparams = runparams_in;
 771         runparams.isLastPar = (pit == pit_type(paragraphs.size() - 1));
 772         // We reinitialize par begin and end to be on the safe side
 773         // with embedded inset as we don't know if they set those
 774         // value correctly.
 775         runparams.par_begin = 0;
 776         runparams.par_end = 0;
 777
 778         bool const maintext = text.isMainText();
 779         // we are at the beginning of an inset and CJK is already open;
 780         // we count inheritation levels to get the inset nesting right.
 781         OutputState * state = getOutputState();
 782         if (pit == 0 && !maintext
 783             && (state->cjk_inherited_ > 0 || state->open_encoding_ == CJK)) {
 784                 state->cjk_inherited_ += 1;
 785                 state->open_encoding_ = none;
 786         }
 787
 788         // This paragraph is merged and we do not show changes in the output
 789         bool const merged_par = !bparams.output_changes && par.parEndChange().deleted();
 790
 791         if (text.inset().isPassThru()) {
 792                 Font const outerfont = text.outerFont(pit);
 793
 794                 // No newline before first paragraph in this lyxtext
 795                 if (pit > 0 && !text.inset().getLayout().parbreakIgnored() && !merged_par) {
 796                         os << '\n';
 797                         if (!text.inset().getLayout().parbreakIsNewline())
 798                                 os << '\n';
 799                 }
 800
 801                 par.latex(bparams, outerfont, os, runparams, start_pos, end_pos, force);
 802                 return;
 803         }
 804
 805         Paragraph const * nextpar = runparams.isLastPar
 806                 ? nullptr : &paragraphs.at(pit + 1);
 807
 808         bool const intitle_command = style.intitle && style.isCommand();
 809         // Intitle commands switch languages locally, thus increase
 810         // language nesting level
 811         if (intitle_command)
 812                 state->nest_level_ += 1;
 813
 814         if (style.pass_thru) {
 815                 Font const outerfont = text.outerFont(pit);
 816                 parStartCommand(par, os, runparams, style);
 817                 if (style.isCommand() && style.needprotect)
 818                         // Due to the moving argument, some fragile
 819                         // commands (labels, index entries)
 820                         // are output after this command (#2154)
 821                         runparams.postpone_fragile_stuff = true;
 822                 if (intitle_command)
 823                         os << '{';
 824
 825                 par.latex(bparams, outerfont, os, runparams, start_pos, end_pos, force);
 826
 827                 // I did not create a parEndCommand for this minuscule
 828                 // task because in the other user of parStartCommand
 829                 // the code is different (JMarc)
 830                 if (style.isCommand()) {
 831                         os << "}";
 832                         if (par.needsCProtection(runparams.moving_arg)
 833                             && contains(runparams.active_chars, '^'))
 834                                 os << "\\endgroup";
 835                         if (merged_par)
 836                                 os << "{}";
 837                         else
 838                                 os << "\n";
 839                 }
 840                 else if (!merged_par)
 841                         os << '\n';
 842                 if (!style.parbreak_is_newline && !merged_par) {
 843                         os << '\n';
 844                 } else if (nextpar && !style.isEnvironment()) {
 845                         Layout const nextstyle = text.inset().forcePlainLayout()
 846                                 ? bparams.documentClass().plainLayout()
 847                                 : nextpar->layout();
 848                         if (nextstyle.name() != style.name() && !merged_par)
 849                                 os << '\n';
 850                 }
 851
 852                 return;
 853         }
 854
 855         // This paragraph's language
 856         Language const * const par_language = par.getParLanguage(bparams);
 857         Language const * const nextpar_language = nextpar ?
 858                 nextpar->getParLanguage(bparams) : nullptr;
 859         // The document's language
 860         Language const * const doc_language = bparams.language;
 861         // The language that was in effect when the environment this paragraph is
 862         // inside of was opened
 863         Language const * const outer_language =
 864                 (runparams.local_font != nullptr) ?
 865                         runparams.local_font->language() : doc_language;
 866
 867         Paragraph const * priorpar = (pit == 0) ? nullptr : &paragraphs.at(pit - 1);
 868
 869         // The previous language that was in effect is the language of the
 870         // previous paragraph, unless the previous paragraph is inside an
 871         // environment with nesting depth greater than (or equal to, but with
 872         // a different layout) the current one. If there is no previous
 873         // paragraph, the previous language is the outer language.
 874         // Note further that we take the outer language also if the prior par
 875         // is PassThru, since in that case it has latex_language, and all secondary
 876         // languages have been closed (#10793).
 877         bool const use_prev_env_language = state->prev_env_language_ != nullptr
 878                         && priorpar
 879                         && priorpar->layout().isEnvironment()
 880                         && (priorpar->getDepth() > par.getDepth()
 881                             || (priorpar->getDepth() == par.getDepth()
 882                                 && priorpar->layout() != par.layout()));
 883
 884         // We need to ignore previous intitle commands since languages
 885         // are switched locally there (# 11514)
 886         // There might be paragraphs before the title, so we check this.
 887         Paragraph * prior_nontitle_par = nullptr;
 888         if (!intitle_command) {
 889                 pit_type ppit = pit;
 890                 while (ppit > 0) {
 891                         --ppit;
 892                         Paragraph const * tmppar = &paragraphs.at(ppit);
 893                         if (tmppar->layout().intitle && tmppar->layout().isCommand())
 894                                 continue;
 895                         prior_nontitle_par = const_cast<Paragraph*>(tmppar);
 896                         break;
 897                 }
 898         }
 899         Language const * const prev_language =
 900                 runparams_in.for_search
 901                         ? languages.getLanguage("ignore")
 902                         : (prior_nontitle_par && !prior_nontitle_par->isPassThru())
 903                                 ? (use_prev_env_language
 904                                         ? state->prev_env_language_
 905                                         : prior_nontitle_par->getParLanguage(bparams))
 906                                 : outer_language;
 907
 908         bool const use_polyglossia = runparams.use_polyglossia;
 909         string const par_lang = use_polyglossia ?
 910                 getPolyglossiaEnvName(par_language): par_language->babel();
 911         string const prev_lang = use_polyglossia ?
 912                 getPolyglossiaEnvName(prev_language) : prev_language->babel();
 913         string const outer_lang = use_polyglossia ?
 914                 getPolyglossiaEnvName(outer_language) : outer_language->babel();
 915         string const nextpar_lang = nextpar_language ? (use_polyglossia ?
 916                 getPolyglossiaEnvName(nextpar_language) :
 917                 nextpar_language->babel()) : string();
 918         string lang_begin_command = use_polyglossia ?
 919                 "\\begin{$$lang}$$opts" : lyxrc.language_command_begin;
 920         string lang_end_command = use_polyglossia ?
 921                 "\\end{$$lang}" : lyxrc.language_command_end;
 922         // the '%' is necessary to prevent unwanted whitespace
 923         string lang_command_termination = "%\n";
 924         bool const using_begin_end = use_polyglossia ||
 925                                         !lang_end_command.empty();
 926
 927         // For InTitle commands, we need to switch the language inside the command
 928         // (see #10849); thus open the command here.
 929         if (intitle_command) {
 930                 parStartCommand(par, os, runparams, style);
 931                 if (style.isCommand() && style.needprotect)
 932                         // Due to the moving argument, some fragile
 933                         // commands (labels, index entries)
 934                         // are output after this command (#2154)
 935                         runparams.postpone_fragile_stuff = true;
 936                 os << '{';
 937         }
 938
 939         // In some insets (such as Arguments), we cannot use \selectlanguage.
 940         // Also, if an RTL language is set via environment in polyglossia,
 941         // only a nested \\text<lang> command will reset the direction for LTR
 942         // languages (see # 10111).
 943         bool const in_polyglossia_rtl_env =
 944                 use_polyglossia
 945                 && runparams.local_font != nullptr
 946                 && outer_language->rightToLeft()
 947                 && !par_language->rightToLeft();
 948         bool const localswitch =
 949                         (runparams_in.for_search
 950                         || text.inset().forceLocalFontSwitch()
 951                         || (using_begin_end && text.inset().forcePlainLayout())
 952                         || in_polyglossia_rtl_env)
 953                         && !text.inset().forceParDirectionSwitch();
 954         if (localswitch) {
 955                 lang_begin_command = use_polyglossia ?
 956                             "\\text$$lang$$opts{" : lyxrc.language_command_local;
 957                 lang_end_command = "}";
 958                 lang_command_termination.clear();
 959         }
 960
 961         bool const localswitch_needed = localswitch && par_lang != outer_lang;
 962
 963         // localswitches need to be closed and reopened at each par
 964         if (runparams_in.for_search || ((par_lang != prev_lang || localswitch_needed)
 965              // check if we already put language command in TeXEnvironment()
 966              && !(style.isEnvironment()
 967                   && (pit == 0 || (priorpar->layout() != par.layout()
 968                                    && priorpar->getDepth() <= par.getDepth())
 969                       || priorpar->getDepth() < par.getDepth())))) {
 970                 if (!localswitch
 971                     && (!using_begin_end || langOpenedAtThisLevel(state))
 972                     && !lang_end_command.empty()
 973                     && prev_lang != outer_lang
 974                     && !prev_lang.empty()
 975                     && (!using_begin_end || !style.isEnvironment())) {
 976                         os << from_ascii(subst(lang_end_command,
 977                                                "$$lang",
 978                                                prev_lang))
 979                            << lang_command_termination;
 980                         if (using_begin_end)
 981                                 popLanguageName();
 982                 }
 983
 984                 // We need to open a new language if we couldn't close the previous
 985                 // one (because there's no language_command_end); and even if we closed
 986                 // the previous one, if the current language is different than the
 987                 // outer_language (which is currently in effect once the previous one
 988                 // is closed).
 989                 if ((lang_end_command.empty() || par_lang != outer_lang
 990                      || (!using_begin_end
 991                          || (style.isEnvironment() && par_lang != prev_lang)))
 992                         && !par_lang.empty()) {
 993                         // If we're inside an inset, and that inset is within an \L or \R
 994                         // (or equivalents), then within the inset, too, any opposite
 995                         // language paragraph should appear within an \L or \R (in addition
 996                         // to, outside of, the normal language switch commands).
 997                         // This behavior is not correct for ArabTeX, though.
 998                         if (!using_begin_end
 999                             // not for ArabTeX
1000                             && par_language->lang() != "arabic_arabtex"
1001                             && outer_language->lang() != "arabic_arabtex"
1002                             // are we in an inset?
1003                             && runparams.local_font != nullptr
1004                             // is the inset within an \L or \R?
1005                             //
1006                             // FIXME: currently, we don't check this; this means that
1007                             // we'll have unnnecessary \L and \R commands, but that
1008                             // doesn't seem to hurt (though latex will complain)
1009                             //
1010                             // is this paragraph in the opposite direction?
1011                             && runparams.local_font->isRightToLeft() != par_language->rightToLeft()) {
1012                                 // FIXME: I don't have a working copy of the Arabi package, so
1013                                 // I'm not sure if the farsi and arabic_arabi stuff is correct
1014                                 // or not...
1015                                 if (par_language->lang() == "farsi")
1016                                         os << "\\textFR{";
1017                                 else if (outer_language->lang() == "farsi")
1018                                         os << "\\textLR{";
1019                                 else if (par_language->lang() == "arabic_arabi")
1020                                         os << "\\textAR{";
1021                                 else if (outer_language->lang() == "arabic_arabi")
1022                                         os << "\\textLR{";
1023                                 // remaining RTL languages currently is hebrew
1024                                 else if (par_language->rightToLeft())
1025                                         os << "\\R{";
1026                                 else
1027                                         os << "\\L{";
1028                         }
1029                         // With CJK, the CJK tag has to be closed first (see below)
1030                         if ((runparams.encoding->package() != Encoding::CJK
1031                                  || bparams.useNonTeXFonts
1032                                  || runparams.for_search)
1033                             && (par_lang != openLanguageName(state) || localswitch || intitle_command)
1034                             && !par_lang.empty()) {
1035                                 string bc = use_polyglossia ?
1036                                           getPolyglossiaBegin(lang_begin_command, par_lang,
1037                                                               par_language->polyglossiaOpts(),
1038                                                               localswitch)
1039                                           : subst(lang_begin_command, "$$lang", par_lang);
1040                                 os << bc;
1041                                 os << lang_command_termination;
1042                                 if (using_begin_end)
1043                                         pushLanguageName(par_lang, localswitch);
1044                         }
1045                 }
1046         }
1047
1048         // Switch file encoding if necessary; no need to do this for "auto-legacy-plain"
1049         // encoding, since this only affects the position of the outputted
1050         // \inputencoding command; the encoding switch will occur when necessary
1051         if (bparams.inputenc == "auto-legacy"
1052                 && !runparams.isFullUnicode() // Xe/LuaTeX use one document-wide encoding  (see also switchEncoding())
1053                 && runparams.encoding->package() != Encoding::japanese
1054                 && runparams.encoding->package() != Encoding::none) {
1055                 // Look ahead for future encoding changes.
1056                 // We try to output them at the beginning of the paragraph,
1057                 // since the \inputencoding command is not allowed e.g. in
1058                 // sections. For this reason we only set runparams.moving_arg
1059                 // after checking for the encoding change, otherwise the
1060                 // change would be always avoided by switchEncoding().
1061                 for (pos_type i = 0; i < par.size(); ++i) {
1062                         char_type const c = par.getChar(i);
1063                         Encoding const * const encoding =
1064                                 par.getFontSettings(bparams, i).language()->encoding();
1065                         if (encoding->package() != Encoding::CJK
1066                                 && runparams.encoding->package() == Encoding::inputenc
1067                                 && isASCII(c))
1068                                 continue;
1069                         if (par.isInset(i))
1070                                 break;
1071                         // All characters before c are in the ASCII range, and
1072                         // c is non-ASCII (but no inset), so change the
1073                         // encoding to that required by the language of c.
1074                         // With CJK, only add switch if we have CJK content at the beginning
1075                         // of the paragraph
1076                         if (i != 0 && encoding->package() == Encoding::CJK)
1077                                 continue;
1078
1079                         pair<bool, int> enc_switch = switchEncoding(os.os(),
1080                                                 bparams, runparams, *encoding);
1081                         // the following is necessary after a CJK environment in a multilingual
1082                         // context (nesting issue).
1083                         if (par_language->encoding()->package() == Encoding::CJK
1084                                 && state->open_encoding_ != CJK && state->cjk_inherited_ == 0) {
1085                                 os << "\\begin{CJK}{"
1086                                    << from_ascii(par_language->encoding()->latexName())
1087                                    << "}{" << from_ascii(bparams.fonts_cjk) << "}%\n";
1088                                 state->open_encoding_ = CJK;
1089                         }
1090                         if (encoding->package() != Encoding::none && enc_switch.first) {
1091                                 if (enc_switch.second > 0) {
1092                                         // the '%' is necessary to prevent unwanted whitespace
1093                                         os << "%\n";
1094                                 }
1095                                 // With CJK, the CJK tag had to be closed first (see above)
1096                                 if (runparams.encoding->package() == Encoding::CJK
1097                                     && par_lang != openLanguageName(state)
1098                                     && !par_lang.empty()) {
1099                                         os << subst(lang_begin_command, "$$lang", par_lang)
1100                                            << lang_command_termination;
1101                                         if (using_begin_end)
1102                                                 pushLanguageName(par_lang, localswitch);
1103                                 }
1104                                 runparams.encoding = encoding;
1105                         }
1106                         break;
1107                 }
1108         }
1109
1110         runparams.moving_arg |= style.needprotect;
1111         if (style.needmboxprotect)
1112                 ++runparams.inulemcmd;
1113         Encoding const * const prev_encoding = runparams.encoding;
1114
1115         bool const useSetSpace = bparams.documentClass().provides("SetSpace");
1116         if (par.allowParagraphCustomization()) {
1117                 if (par.params().startOfAppendix()) {
1118                         os << "\n\\appendix\n";
1119                 }
1120
1121                 // InTitle commands must use switches (not environments)
1122                 // inside the commands (see #9332)
1123                 if (style.intitle) {
1124                         if (!par.params().spacing().isDefault())
1125                         {
1126                                 if (runparams.moving_arg)
1127                                         os << "\\protect";
1128                                 os << from_ascii(par.params().spacing().writeCmd(useSetSpace));
1129                         }
1130                 } else {
1131                         if (!par.params().spacing().isDefault()
1132                                 && (pit == 0 || !priorpar->hasSameLayout(par)))
1133                         {
1134                                 os << from_ascii(par.params().spacing().writeEnvirBegin(useSetSpace))
1135                                     << '\n';
1136                         }
1137
1138                         if (style.isCommand()) {
1139                                 os << '\n';
1140                         }
1141                 }
1142         }
1143
1144         // For InTitle commands, we already started the command before
1145         // the language switch
1146         if (!intitle_command) {
1147                 parStartCommand(par, os, runparams, style);
1148                 if (style.isCommand() && style.needprotect)
1149                         // Due to the moving argument, some fragile
1150                         // commands (labels, index entries)
1151                         // are output after this command (#2154)
1152                         runparams.postpone_fragile_stuff = true;
1153         }
1154
1155         Font const outerfont = text.outerFont(pit);
1156
1157         // FIXME UNICODE
1158         os << from_utf8(everypar);
1159         par.latex(bparams, outerfont, os, runparams, start_pos, end_pos, force);
1160
1161         Font const font = par.empty()
1162                  ? par.getLayoutFont(bparams, outerfont)
1163                  : par.getFont(bparams, par.size() - 1, outerfont);
1164
1165         bool const is_command = style.isCommand();
1166
1167         // InTitle commands need to be closed after the language has been closed.
1168         if (!intitle_command) {
1169                 if (is_command) {
1170                         os << '}';
1171                         if (!style.postcommandargs().empty())
1172                                 latexArgInsets(par, os, runparams, style.postcommandargs(), "post:");
1173                         if (!runparams.post_macro.empty()) {
1174                                 // Output the stored fragile commands (labels, indices etc.)
1175                                 // that need to be output after the command with moving argument.
1176                                 os << runparams.post_macro;
1177                                 runparams.post_macro.clear();
1178                         }
1179                         if (par.needsCProtection(runparams.moving_arg)
1180                             && contains(runparams.active_chars, '^'))
1181                                 os << "\\endgroup";
1182                         if (runparams.encoding != prev_encoding) {
1183                                 runparams.encoding = prev_encoding;
1184                                 os << setEncoding(prev_encoding->iconvName());
1185                         }
1186                 }
1187         }
1188
1189         bool pending_newline = false;
1190         bool unskip_newline = false;
1191         bool close_lang_switch = false;
1192         switch (style.latextype) {
1193         case LATEX_ITEM_ENVIRONMENT:
1194         case LATEX_LIST_ENVIRONMENT:
1195                 if ((nextpar && par_lang != nextpar_lang
1196                              && nextpar->getDepth() == par.getDepth())
1197                     || (atSameLastLangSwitchDepth(state) && nextpar
1198                             && nextpar->getDepth() < par.getDepth()))
1199                         close_lang_switch = using_begin_end;
1200                 if (nextpar && par.params().depth() < nextpar->params().depth())
1201                         pending_newline = !text.inset().getLayout().parbreakIgnored() && !merged_par;
1202                 break;
1203         case LATEX_ENVIRONMENT: {
1204                 // if it's the last paragraph of the current environment
1205                 // skip it otherwise fall through
1206                 if (nextpar
1207                     && ((nextpar->layout() != par.layout()
1208                            || nextpar->params().depth() != par.params().depth())
1209                         || (!using_begin_end || par_lang != nextpar_lang)))
1210                 {
1211                         close_lang_switch = using_begin_end;
1212                         break;
1213                 }
1214         }
1215         // possible
1216         // fall through
1217         default:
1218                 // we don't need it for the last paragraph and in InTitle commands!!!
1219                 if (nextpar && !intitle_command)
1220                         pending_newline = !text.inset().getLayout().parbreakIgnored() && !merged_par;
1221         }
1222
1223         // InTitle commands use switches (not environments) for space settings
1224         if (par.allowParagraphCustomization() && !style.intitle) {
1225                 if (!par.params().spacing().isDefault()
1226                         && (runparams.isLastPar || !nextpar->hasSameLayout(par))) {
1227                         if (pending_newline)
1228                                 os << '\n';
1229
1230                         string const endtag =
1231                                 par.params().spacing().writeEnvirEnd(useSetSpace);
1232                         if (prefixIs(endtag, "\\end{"))
1233                                 os << breakln;
1234
1235                         os << from_ascii(endtag);
1236                         pending_newline = true;
1237                 }
1238         }
1239
1240         // Closing the language is needed for the last paragraph in a given language
1241         // as well as for any InTitleCommand (since these set the language locally);
1242         // it is also needed if we're within an \L or \R that we may have opened above
1243         // (not necessarily in this paragraph) and are about to close.
1244         bool closing_rtl_ltr_environment = !using_begin_end
1245                 // not for ArabTeX
1246                 && (par_language->lang() != "arabic_arabtex"
1247                     && outer_language->lang() != "arabic_arabtex")
1248                 // have we opened an \L or \R environment?
1249                 && runparams.local_font != nullptr
1250                 && runparams.local_font->isRightToLeft() != par_language->rightToLeft()
1251                 // are we about to close the language?
1252                 &&((nextpar && par_lang != nextpar_lang)
1253                    || (runparams.isLastPar && par_lang != outer_lang));
1254
1255         if (localswitch_needed
1256             || (intitle_command && using_begin_end)
1257             || closing_rtl_ltr_environment
1258             || (((runparams.isLastPar && !runparams.inbranch) || close_lang_switch)
1259                 && (par_lang != outer_lang || (using_begin_end
1260                                                 && style.isEnvironment()
1261                                                 && par_lang != nextpar_lang)))) {
1262                 // Since \selectlanguage write the language to the aux file,
1263                 // we need to reset the language at the end of footnote or
1264                 // float.
1265
1266                 if (!localswitch && (pending_newline || close_lang_switch))
1267                         os << '\n';
1268
1269                 // when the paragraph uses CJK, the language has to be closed earlier
1270                 if ((font.language()->encoding()->package() != Encoding::CJK)
1271                         || bparams.useNonTeXFonts
1272                         || runparams_in.for_search) {
1273                         if (lang_end_command.empty()) {
1274                                 // If this is a child, we should restore the
1275                                 // master language after the last paragraph.
1276                                 Language const * const current_language =
1277                                         (runparams.isLastPar && runparams.master_language)
1278                                                 ? runparams.master_language
1279                                                 : outer_language;
1280                                 string const current_lang = use_polyglossia
1281                                         ? getPolyglossiaEnvName(current_language)
1282                                         : current_language->babel();
1283                                 if (!current_lang.empty()
1284                                     && current_lang != openLanguageName(state)) {
1285                                         string bc = use_polyglossia ?
1286                                                     getPolyglossiaBegin(lang_begin_command, current_lang,
1287                                                                         current_language->polyglossiaOpts(),
1288                                                                         localswitch)
1289                                                   : subst(lang_begin_command, "$$lang", current_lang);
1290                                         os << bc;
1291                                         pending_newline = !localswitch
1292                                                         && !text.inset().getLayout().parbreakIgnored();
1293                                         unskip_newline = !localswitch;
1294                                         if (using_begin_end)
1295                                                 pushLanguageName(current_lang, localswitch);
1296                                 }
1297                         } else if ((!using_begin_end ||
1298                                     langOpenedAtThisLevel(state)) &&
1299                                    !par_lang.empty()) {
1300                                 // If we are in an environment, we have to
1301                                 // close the "outer" language afterwards
1302                                 string const & cur_lang = openLanguageName(state);
1303                                 if (!style.isEnvironment()
1304                                     || (close_lang_switch
1305                                         && atSameLastLangSwitchDepth(state)
1306                                         && par_lang != outer_lang
1307                                         && (par_lang != cur_lang
1308                                             || (cur_lang != outer_lang
1309                                                 && nextpar
1310                                                 && style != nextpar->layout())))
1311                                     || (atSameLastLangSwitchDepth(state)
1312                                         && state->lang_switch_depth_.size()
1313                                         && cur_lang != par_lang)
1314                                     || in_polyglossia_rtl_env)
1315                                 {
1316                                         if (using_begin_end && !localswitch)
1317                                                 os << breakln;
1318                                         os << from_ascii(subst(
1319                                                 lang_end_command,
1320                                                 "$$lang",
1321                                                 par_lang));
1322                                         pending_newline = !localswitch
1323                                                         && !text.inset().getLayout().parbreakIgnored();
1324                                         unskip_newline = !localswitch;
1325                                         if (using_begin_end)
1326                                                 popLanguageName();
1327                                 }
1328                         }
1329                 }
1330         }
1331         if (closing_rtl_ltr_environment)
1332                 os << "}";
1333
1334         // InTitle commands need to be closed after the language has been closed.
1335         if (intitle_command) {
1336                 os << '}';
1337                 if (!style.postcommandargs().empty())
1338                         latexArgInsets(par, os, runparams, style.postcommandargs(), "post:");
1339                 if (!runparams.post_macro.empty()) {
1340                         // Output the stored fragile commands (labels, indices etc.)
1341                         // that need to be output after the command with moving argument.
1342                         os << runparams.post_macro;
1343                         runparams.post_macro.clear();
1344                 }
1345                 if (par.needsCProtection(runparams.moving_arg)
1346                     && contains(runparams.active_chars, '^'))
1347                         os << "\\endgroup";
1348                 if (runparams.encoding != prev_encoding) {
1349                         runparams.encoding = prev_encoding;
1350                         os << setEncoding(prev_encoding->iconvName());
1351                 }
1352         }
1353
1354         bool const last_was_separator =
1355                 par.size() > 0 && par.isEnvSeparator(par.size() - 1);
1356
1357         // Signify added/deleted par break in output if show changes in output
1358         if (nextpar && !os.afterParbreak() && !last_was_separator
1359             && bparams.output_changes && par.parEndChange().changed()) {
1360                 Changes::latexMarkChange(os, bparams, Change(Change::UNCHANGED),
1361                                          par.parEndChange(), runparams);
1362                 os << bparams.encoding().latexString(docstring(1, 0x00b6)).first << "}";
1363         }
1364
1365         if (pending_newline) {
1366                 if (unskip_newline)
1367                         // prevent unwanted whitespace
1368                         os << '%';
1369                 if (!os.afterParbreak() && !last_was_separator)
1370                         os << '\n';
1371         }
1372
1373         // if this is a CJK-paragraph and the next isn't, close CJK
1374         // also if the next paragraph is a multilingual environment (because of nesting)
1375         if (nextpar && state->open_encoding_ == CJK
1376                 && bparams.encoding().iconvName() != "UTF-8"
1377                 && bparams.encoding().package() != Encoding::CJK
1378                 && (nextpar_language->encoding()->package() != Encoding::CJK
1379                         || (nextpar->layout().isEnvironment() && nextpar->isMultiLingual(bparams)))
1380                 // inbetween environments, CJK has to be closed later (nesting!)
1381                 && (!style.isEnvironment() || !nextpar->layout().isEnvironment())) {
1382                 os << "\\end{CJK}\n";
1383                 state->open_encoding_ = none;
1384         }
1385
1386         // If this is the last paragraph, close the CJK environment
1387         // if necessary. If it's an environment or nested in an environment,
1388         // we'll have to \end that first.
1389         if (runparams.isLastPar && !style.isEnvironment()
1390                 && par.params().depth() < 1) {
1391                 switch (state->open_encoding_) {
1392                         case CJK: {
1393                                 // do nothing at the end of child documents
1394                                 if (maintext && buf.masterBuffer() != &buf)
1395                                         break;
1396                                 // end of main text: also insert a \clearpage (see #5386)
1397                                 if (maintext) {
1398                                         os << "\n\\clearpage\n\\end{CJK}\n";
1399                                 // end of an inset
1400                                 } else
1401                                         os << "\\end{CJK}";
1402                                 state->open_encoding_ = none;
1403                                 break;
1404                         }
1405                         case inputenc: {
1406                                 // FIXME: If we are in an inset and the switch happened outside this inset,
1407                                 // do not switch back at the end of the inset (bug #8479)
1408                                 // The following attempt does not help with listings-caption in a CJK document:
1409                                 // if (runparams_in.local_font != 0
1410                                 //    && runparams_in.encoding == runparams_in.local_font->language()->encoding())
1411                                 //      break;
1412                                 os << "\\egroup";
1413                                 state->open_encoding_ = none;
1414                                 break;
1415                         }
1416                         case none:
1417                         default:
1418                                 // do nothing
1419                                 break;
1420                 }
1421         }
1422
1423         // Information about local language is stored as a font feature.
1424         // If this is the last paragraph of the inset and a local_font was set upon entering
1425         // and we are mixing encodings ("auto-legacy" or "auto-legacy-plain" and no XeTeX or LuaTeX),
1426         // ensure the encoding is set back to the default encoding of the local language.
1427         if (runparams.isLastPar && runparams_in.local_font != nullptr
1428             && runparams_in.encoding != runparams_in.local_font->language()->encoding()
1429             && (bparams.inputenc == "auto-legacy" || bparams.inputenc == "auto-legacy-plain")
1430                 && !runparams.isFullUnicode()
1431            ) {
1432                 runparams_in.encoding = runparams_in.local_font->language()->encoding();
1433                 os << setEncoding(runparams_in.encoding->iconvName());
1434         }
1435         // Otherwise, the current encoding should be set for the next paragraph.
1436         else
1437                 runparams_in.encoding = runparams.encoding;
1438
1439         // Also pass the post_macros upstream
1440         runparams_in.post_macro = runparams.post_macro;
1441
1442
1443         // we don't need a newline for the last paragraph!!!
1444         // Note from JMarc: we will re-add a \n explicitly in
1445         // TeXEnvironment, because it is needed in this case
1446         if (nextpar && !os.afterParbreak() && !last_was_separator) {
1447                 Layout const & next_layout = nextpar->layout();
1448                 if (!text.inset().getLayout().parbreakIgnored() && !merged_par)
1449                         // Make sure to start a new line
1450                         os << breakln;
1451                 // A newline '\n' is always output before a command,
1452                 // so avoid doubling it.
1453                 if (!next_layout.isCommand()) {
1454                         // Here we now try to avoid spurious empty lines by
1455                         // outputting a paragraph break only if: (case 1) the
1456                         // paragraph style allows parbreaks and no \begin, \end
1457                         // or \item tags are going to follow (i.e., if the next
1458                         // isn't the first or the current isn't the last
1459                         // paragraph of an environment or itemize) and the
1460                         // depth and alignment of the following paragraph is
1461                         // unchanged, or (case 2) the following is a
1462                         // non-environment paragraph whose depth is increased
1463                         // but whose alignment is unchanged, or (case 3) the
1464                         // paragraph is not an environment and the next one is a
1465                         // non-itemize-like env at lower depth, or (case 4) the
1466                         // paragraph is a command not followed by an environment
1467                         // and the alignment of the current and next paragraph
1468                         // is unchanged, or (case 5) the current alignment is
1469                         // changed and a standard paragraph follows.
1470                         DocumentClass const & tclass = bparams.documentClass();
1471                         if ((style == next_layout
1472                              && !style.parbreak_is_newline
1473                              && !text.inset().getLayout().parbreakIsNewline()
1474                              && !text.inset().getLayout().parbreakIgnored()
1475                              && style.latextype != LATEX_ITEM_ENVIRONMENT
1476                              && style.latextype != LATEX_LIST_ENVIRONMENT
1477                              && style.align == par.getAlign(bparams)
1478                              && nextpar->getDepth() == par.getDepth()
1479                              && nextpar->getAlign(bparams) == par.getAlign(bparams))
1480                             || (!next_layout.isEnvironment()
1481                                 && nextpar->getDepth() > par.getDepth()
1482                                 && nextpar->getAlign(bparams) == next_layout.align)
1483                             || (!style.isEnvironment()
1484                                 && next_layout.latextype == LATEX_ENVIRONMENT
1485                                 && nextpar->getDepth() < par.getDepth())
1486                             || (style.isCommand()
1487                                 && !next_layout.isEnvironment()
1488                                 && style.align == par.getAlign(bparams)
1489                                 && next_layout.align == nextpar->getAlign(bparams))
1490                             || (style.align != par.getAlign(bparams)
1491                                 && tclass.isDefaultLayout(next_layout))) {
1492                                 // and omit paragraph break if it has been deleted with ct
1493                                 // and changes are not shown in output
1494                                 if (!merged_par)
1495                                         os << '\n';
1496                         }
1497                 }
1498         }
1499
1500         // Reset language nesting level after intitle command
1501         if (intitle_command)
1502                 state->nest_level_ -= 1;
1503
1504         LYXERR(Debug::LATEX, "TeXOnePar for paragraph " << pit << " done; ptr "
1505                 << &par << " next " << nextpar);
1506
1507         return;
1508 }
1509
1510
1511 // LaTeX all paragraphs
1512 void latexParagraphs(Buffer const & buf,
1513                      Text const & text,
1514                      otexstream & os,
1515                      OutputParams const & runparams,
1516                      string const & everypar)
1517 {
1518         LASSERT(runparams.par_begin <= runparams.par_end,
1519                 { os << "% LaTeX Output Error\n"; return; } );
1520
1521         BufferParams const & bparams = buf.params();
1522         BufferParams const & mparams = buf.masterParams();
1523
1524         bool const maintext = text.isMainText();
1525         bool const is_child = buf.masterBuffer() != &buf;
1526         bool const multibib_child = maintext && is_child
1527                         && mparams.multibib == "child";
1528
1529         if (multibib_child && mparams.useBiblatex())
1530                 os << "\\newrefsection";
1531         else if (multibib_child && mparams.useBibtopic()
1532                  && !buf.masterBibInfo().empty()) {
1533                 os << "\\begin{btUnit}\n";
1534                 runparams.openbtUnit = true;
1535         }
1536
1537         // Open a CJK environment at the beginning of the main buffer
1538         // if the document's main encoding requires the CJK package
1539         // or the document encoding is utf8 and the CJK package is required
1540         // (but not in child documents or documents using system fonts):
1541         OutputState * state = getOutputState();
1542         if (maintext && !is_child && !bparams.useNonTeXFonts
1543             && (bparams.encoding().package() == Encoding::CJK
1544                         || (bparams.encoding().name() == "utf8"
1545                                 && runparams.use_CJK))
1546            ) {
1547                 docstring const cjkenc = bparams.encoding().iconvName() == "UTF-8"
1548                                                                  ? from_ascii("UTF8")
1549                                                                  : from_ascii(bparams.encoding().latexName());
1550                 os << "\\begin{CJK}{" << cjkenc
1551                    << "}{" << from_ascii(bparams.fonts_cjk) << "}%\n";
1552                 state->open_encoding_ = CJK;
1553         }
1554         // if "auto begin" is switched off, explicitly switch the
1555         // language on at start
1556         string const mainlang = runparams.use_polyglossia
1557                 ? getPolyglossiaEnvName(bparams.language)
1558                 : bparams.language->babel();
1559         string const lang_begin_command = runparams.use_polyglossia ?
1560                 "\\begin{$$lang}$$opts" : lyxrc.language_command_begin;
1561         string const lang_end_command = runparams.use_polyglossia ?
1562                 "\\end{$$lang}" : lyxrc.language_command_end;
1563         bool const using_begin_end = runparams.use_polyglossia ||
1564                                         !lang_end_command.empty();
1565
1566         if (maintext && !lyxrc.language_auto_begin &&
1567             !mainlang.empty()) {
1568                 // FIXME UNICODE
1569                 string bc = runparams.use_polyglossia ?
1570                             getPolyglossiaBegin(lang_begin_command, mainlang,
1571                                                 bparams.language->polyglossiaOpts())
1572                           : subst(lang_begin_command, "$$lang", mainlang);
1573                 os << bc;
1574                 os << '\n';
1575                 if (using_begin_end)
1576                         pushLanguageName(mainlang);
1577         }
1578
1579         ParagraphList const & paragraphs = text.paragraphs();
1580
1581         if (runparams.par_begin == runparams.par_end) {
1582                 // The full doc will be exported but it is easier to just rely on
1583                 // runparams range parameters that will be passed TeXEnvironment.
1584                 runparams.par_begin = 0;
1585                 runparams.par_end = paragraphs.size();
1586         }
1587
1588         pit_type pit = runparams.par_begin;
1589         // lastpit is for the language check after the loop.
1590         pit_type lastpit = pit;
1591         // variables used in the loop:
1592         bool was_title = false;
1593         bool already_title = false;
1594         DocumentClass const & tclass = bparams.documentClass();
1595
1596         // Did we already warn about inTitle layout mixing? (we only warn once)
1597         bool gave_layout_warning = false;
1598         for (; pit < runparams.par_end; ++pit) {
1599                 lastpit = pit;
1600                 ParagraphList::const_iterator par = paragraphs.constIterator(pit);
1601
1602                 // FIXME This check should not be needed. We should
1603                 // perhaps issue an error if it is.
1604                 Layout const & layout = text.inset().forcePlainLayout() ?
1605                                 tclass.plainLayout() : par->layout();
1606
1607                 if (layout.intitle) {
1608                         if (already_title) {
1609                                 if (!gave_layout_warning && !runparams.dryrun) {
1610                                         gave_layout_warning = true;
1611                                         frontend::Alert::warning(_("Error in latexParagraphs"),
1612                                                         bformat(_("You are using at least one "
1613                                                           "layout (%1$s) intended for the title, "
1614                                                           "after using non-title layouts. This "
1615                                                           "could lead to missing or incorrect output."
1616                                                           ), layout.name()));
1617                                 }
1618                         } else if (!was_title) {
1619                                 was_title = true;
1620                                 if (tclass.titletype() == TITLE_ENVIRONMENT) {
1621                                         os << "\\begin{"
1622                                                         << from_ascii(tclass.titlename())
1623                                                         << "}\n";
1624                                 }
1625                         }
1626                 } else if (was_title && !already_title && !layout.inpreamble) {
1627                         if (tclass.titletype() == TITLE_ENVIRONMENT) {
1628                                 os << "\\end{" << from_ascii(tclass.titlename())
1629                                                 << "}\n";
1630                         }
1631                         else {
1632                                 os << "\\" << from_ascii(tclass.titlename())
1633                                                 << "\n";
1634                         }
1635                         already_title = true;
1636                         was_title = false;
1637                 }
1638
1639                 if (layout.isCommand() && !layout.latexname().empty()
1640                     && layout.latexname() == bparams.multibib) {
1641                         if (runparams.openbtUnit)
1642                                 os << "\\end{btUnit}\n";
1643                         if (!bparams.useBiblatex()
1644                             && !buf.masterBibInfo().empty()) {
1645                                 os << '\n' << "\\begin{btUnit}\n";
1646                                 runparams.openbtUnit = true;
1647                         }
1648                 }
1649
1650                 if (!layout.isEnvironment() && par->params().leftIndent().zero()) {
1651                         // This is a standard top level paragraph, TeX it and continue.
1652                         TeXOnePar(buf, text, pit, os, runparams, everypar);
1653                         continue;
1654                 }
1655
1656                 // Do not output empty environments if the whole paragraph has
1657                 // been deleted with ct and changes are not output.
1658                 if (size_t(pit + 1) < paragraphs.size()) {
1659                         ParagraphList::const_iterator nextpar = paragraphs.constIterator(pit + 1);
1660                         Paragraph const & cpar = paragraphs.at(pit);
1661                         if ((par->layout() != nextpar->layout()
1662                              || par->params().depth() == nextpar->params().depth()
1663                              || par->params().leftIndent() == nextpar->params().leftIndent())
1664                             && !runparams.for_search && cpar.size() > 0
1665                             && cpar.isDeleted(0, cpar.size()) && !bparams.output_changes) {
1666                                 if (!bparams.output_changes && !cpar.parEndChange().deleted())
1667                                         os << '\n' << '\n';
1668                                 continue;
1669                         }
1670                 }
1671
1672                 TeXEnvironmentData const data =
1673                         prepareEnvironment(buf, text, par, os, runparams);
1674                 // pit can be changed in TeXEnvironment.
1675                 TeXEnvironment(buf, text, runparams, pit, os);
1676                 finishEnvironment(os, runparams, data);
1677         }
1678
1679         // FIXME: uncomment the content or remove this block
1680         if (pit == runparams.par_end) {
1681                         // Make sure that the last paragraph is
1682                         // correctly terminated (because TeXOnePar does
1683                         // not add a \n in this case)
1684                         //os << '\n';
1685         }
1686
1687         // It might be that we only have a title in this document
1688         if (was_title && !already_title) {
1689                 if (tclass.titletype() == TITLE_ENVIRONMENT) {
1690                         os << "\\end{" << from_ascii(tclass.titlename())
1691                            << "}\n";
1692                 } else {
1693                         os << "\\" << from_ascii(tclass.titlename())
1694                            << "\n";
1695                 }
1696         }
1697
1698         if (maintext && !is_child && runparams.openbtUnit)
1699                 os << "\\end{btUnit}\n";
1700
1701         // if "auto end" is switched off, explicitly close the language at the end
1702         // but only if the last par is in a babel or polyglossia language
1703         Language const * const lastpar_language =
1704                         paragraphs.at(lastpit).getParLanguage(bparams);
1705         if (maintext && !lyxrc.language_auto_end && !mainlang.empty() &&
1706                 lastpar_language->encoding()->package() != Encoding::CJK) {
1707                 os << from_utf8(subst(lang_end_command,
1708                                         "$$lang",
1709                                         mainlang))
1710                         << '\n';
1711                 // If we have language_auto_begin, the stack will
1712                 // already be empty, nothing to pop()
1713                 if (using_begin_end && !lyxrc.language_auto_begin)
1714                         popLanguageName();
1715         }
1716
1717         // If the last paragraph is an environment, we'll have to close
1718         // CJK at the very end to do proper nesting.
1719         if (maintext && !is_child && state->open_encoding_ == CJK) {
1720                 os << "\\clearpage\n\\end{CJK}\n";
1721                 state->open_encoding_ = none;
1722         }
1723         // Likewise for polyglossia or when using begin/end commands
1724         // or at the very end of an active branch inset with a language switch
1725         Language const * const outer_language = (runparams.local_font != nullptr)
1726                         ? runparams.local_font->language() : bparams.language;
1727         string const & prev_lang = runparams.use_polyglossia
1728                         ? getPolyglossiaEnvName(outer_language)
1729                         : outer_language->babel();
1730         string const lastpar_lang = runparams.use_polyglossia ?
1731                 getPolyglossiaEnvName(lastpar_language): lastpar_language->babel();
1732         string const & cur_lang = openLanguageName(state);
1733         if (((runparams.inbranch && langOpenedAtThisLevel(state) && prev_lang != cur_lang)
1734              || (maintext && !is_child)) && !cur_lang.empty()) {
1735                 os << from_utf8(subst(lang_end_command,
1736                                         "$$lang",
1737                                         cur_lang))
1738                    << '\n';
1739                 if (using_begin_end)
1740                         popLanguageName();
1741         } else if (runparams.inbranch && !using_begin_end
1742                    && prev_lang != lastpar_lang && !lastpar_lang.empty()) {
1743                 // with !using_begin_end, cur_lang is empty, so we need to
1744                 // compare against the paragraph language (and we are in the
1745                 // last paragraph at this point)
1746                 os << subst(lang_begin_command, "$$lang", prev_lang) << '\n';
1747         }
1748
1749         // reset inherited encoding
1750         if (state->cjk_inherited_ > 0) {
1751                 state->cjk_inherited_ -= 1;
1752                 if (state->cjk_inherited_ == 0)
1753                         state->open_encoding_ = CJK;
1754         }
1755
1756         if (multibib_child && mparams.useBibtopic()) {
1757                 os << "\\end{btUnit}\n";
1758                 runparams.openbtUnit = false;
1759         }
1760 }
1761
1762 // Switch the input encoding for some part(s) of the document.
1763 pair<bool, int> switchEncoding(odocstream & os, BufferParams const & bparams,
1764                    OutputParams const & runparams, Encoding const & newEnc,
1765                    bool force, bool noswitchmacro)
1766 {
1767         // Never switch encoding with XeTeX/LuaTeX
1768         // or if we're in a moving argument or inherit the outer encoding.
1769         if (runparams.isFullUnicode() || newEnc.name() == "inherit")
1770                 return make_pair(false, 0);
1771
1772         // Only switch for auto-selected legacy encodings (inputenc setting
1773         // "auto-legacy" or "auto-legacy-plain").
1774         // The "listings" environment can force a switch also with other
1775         // encoding settings (it does not support variable width encodings
1776         // (utf8, jis, ...) under 8-bit latex engines).
1777         if (!force && ((bparams.inputenc != "auto-legacy" && bparams.inputenc != "auto-legacy-plain")
1778                                    || runparams.moving_arg))
1779                 return make_pair(false, 0);
1780
1781         Encoding const & oldEnc = *runparams.encoding;
1782         // Do not switch, if the encoding is unchanged or switching is not supported.
1783         if (oldEnc.name() == newEnc.name()
1784                 || oldEnc.package() == Encoding::japanese
1785                 || oldEnc.package() == Encoding::none
1786                 || newEnc.package() == Encoding::none
1787                 || runparams.for_search)
1788                 return make_pair(false, 0);
1789         // FIXME We ignore encoding switches from/to encodings that do
1790         // neither support the inputenc package nor the CJK package here.
1791         // This may fail for characters not supported by "unicodesymbols"
1792         // or for non-ASCII characters in "listings"
1793         // but it is the best we can do.
1794
1795         // change encoding
1796         LYXERR(Debug::LATEX, "Changing LaTeX encoding from "
1797                    << oldEnc.name() << " to " << newEnc.name());
1798         os << setEncoding(newEnc.iconvName());
1799         if (bparams.inputenc == "auto-legacy-plain")
1800           return make_pair(true, 0);
1801
1802         docstring const inputenc_arg(from_ascii(newEnc.latexName()));
1803         OutputState * state = getOutputState();
1804         switch (newEnc.package()) {
1805                 case Encoding::none:
1806                 case Encoding::japanese:
1807                         // shouldn't ever reach here (see above) but avoids warning.
1808                         return make_pair(true, 0);
1809                 case Encoding::inputenc: {
1810                         int count = inputenc_arg.length();
1811                         if (oldEnc.package() == Encoding::CJK &&
1812                             state->open_encoding_ == CJK) {
1813                                 os << "\\end{CJK}";
1814                                 state->open_encoding_ = none;
1815                                 count += 9;
1816                         }
1817                         else if (oldEnc.package() == Encoding::inputenc &&
1818                                  state->open_encoding_ == inputenc) {
1819                                 os << "\\egroup";
1820                                 state->open_encoding_ = none;
1821                                 count += 7;
1822                         }
1823                         if (runparams.local_font != nullptr
1824                             &&  oldEnc.package() == Encoding::CJK) {
1825                                 // within insets, \inputenc switches need
1826                                 // to be embraced within \bgroup...\egroup;
1827                                 // else CJK fails.
1828                                 os << "\\bgroup";
1829                                 count += 7;
1830                                 state->open_encoding_ = inputenc;
1831                         }
1832                         if (noswitchmacro)
1833                                 return make_pair(true, count);
1834                         os << "\\inputencoding{" << inputenc_arg << '}';
1835                         return make_pair(true, count + 16);
1836                 }
1837                 case Encoding::CJK: {
1838                         int count = inputenc_arg.length();
1839                         if (oldEnc.package() == Encoding::CJK &&
1840                             state->open_encoding_ == CJK) {
1841                                 os << "\\end{CJK}";
1842                                 count += 9;
1843                         }
1844                         if (oldEnc.package() == Encoding::inputenc &&
1845                             state->open_encoding_ == inputenc) {
1846                                 os << "\\egroup";
1847                                 count += 7;
1848                         }
1849                         os << "\\begin{CJK}{"
1850                            << from_ascii(newEnc.latexName()) << "}{"
1851                            << from_ascii(bparams.fonts_cjk) << "}";
1852                         state->open_encoding_ = CJK;
1853                         return make_pair(true, count + 15);
1854                 }
1855         }
1856         // Dead code to avoid a warning:
1857         return make_pair(true, 0);
1858 }
1859
1860 } // namespace lyx